stephen mahler

Modulating Targeting of Poly(ethylene glycol) Particles to Tumor Cells Using Bispecific Antibodies

Publisher: Wiley

Date: 14-03-2019

DOI: 10.1002/ADHM.201801607

Abstract: Low-fouling or "stealth" particles composed of poly(ethylene glycol) (PEG) display a striking ability to evade phagocytic cell uptake. However, functionalizing them for specific targeting is challenging. To address this challenge, stealth PEG particles prepared by a mesoporous silica templating method are functionalized with bispecific antibodies (BsAbs) to obtain PEG-BsAb particles via a one-step binding strategy for cell and tumor targeting. The dual specificity of the BsAbs-one arm binds to the PEG particles while the other targets a cell antigen (epidermal growth factor receptor, EGFR)-is exploited to modulate the number of targeting ligands per particle. Increasing the BsAb incubation concentration increases the amount of BsAb tethered to the PEG particles and enhances targeting and internalization into breast cancer cells overexpressing EGFR. The degree of BsAb functionalization does not significantly reduce the stealth properties of the PEG particles ex vivo, as assessed by their interactions with primary human blood granulocytes and monocytes. Although increasing the BsAb amount on PEG particles does not lead to the expected improvement in tumor accumulation in vivo, BsAb functionalization facilitates tumor cell uptake of PEG particles. This work highlights strategies to balance evading nonspecific clearance pathways, while improving tumor targeting and accumulation.

Role of environmental conditions on the expression levels, glycoform pattern and levels of sialyltransferase for hFSH produced by recombinant CHO cells

Publisher: Springer Science and Business Media LLC

Date: 1994

DOI: 10.1007/BF00762396

Purification of monoclonal antibodies from cell culture supernatants by Gradiflow™ electrophoresis technology

Publisher: Wiley

Date: 25-11-2006

DOI: 10.1002/JCTB.1426

Effect of energy source, salt concentration and loading force on colloidal interactions between Acidithiobacillus ferrooxidans cells and mineral surfaces

Publisher: Elsevier BV

Date: 08-2015

DOI: 10.1016/J.COLSURFB.2015.05.026

Abstract: The surface appendages and extracellular polymeric substances of cells play an important role in the bacterial adhesion process. In this work, colloidal forces and nanomechanical properties of Acidithiobacillus ferrooxidans (A. f) interacted with silicon wafer and pyrite (FeS2) surfaces in solutions of varying salt concentrations were quantitatively examined using the bacterial probe technique with atomic force microscopy. A. f cells were cultured with either ferrous sulfate or elemental sulfur as key energy sources. Our results show that A. f cells grown with ferrous ion and elemental sulfur exhibit distinctive retraction force vs separation distance curves with stair-step and saw tooth shapes, respectively. During the approach of bacterial probes to the substrate surfaces, surface appendages and biopolymers of cells are sequentially compressed. The conformations of surface appendages and biopolymers are significantly influenced by the salt concentrations.

Immunosuppressive human anti-CD83 monoclonal antibody depletion of activated dendritic cells in transplantation

Publisher: Springer Science and Business Media LLC

Date: 19-08-2016

DOI: 10.1038/LEU.2015.231

Abstract: Current immunosuppressive/anti-inflammatory agents target the responding effector arm of the immune response and their nonspecific action increases the risk of infection and malignancy. These effects impact on their use in allogeneic haematopoietic cell transplantation and other forms of transplantation. Interventions that target activated dendritic cells (DCs) have the potential to suppress the induction of undesired immune responses (for ex le, graft versus host disease (GVHD) or transplant rejection) and to leave protective T-cell immune responses intact (for ex le, cytomegalovirus (CMV) immunity). We developed a human IgG1 monoclonal antibody (mAb), 3C12, specific for CD83, which is expressed on activated but not resting DC. The 3C12 mAb and an affinity improved version, 3C12C, depleted CD83(+) cells by CD16(+) NK cell-mediated antibody-dependent cellular cytotoxicity, and inhibited allogeneic T-cell proliferation in vitro. A single dose of 3C12C prevented human peripheral blood mononuclear cell-induced acute GVHD in SCID mouse recipients. The mAb 3C12C depleted CMRF-44(+)CD83(bright) activated DC but spared CD83(dim/-) DC in vivo. It reduced human T-cell activation in vivo and maintained the proportion of CD4(+) FoxP3(+) CD25(+) Treg cells and also viral-specific CD8(+) T cells. The anti-CD83 mAb, 3C12C, merits further evaluation as a new immunosuppressive agent in transplantation.

Overcoming Instability of Antibody-Nanomaterial Conjugates: Next Generation Targeted Nanomedicines Using Bispecific Antibodies

Publisher: Wiley

Date: 10-06-2016

DOI: 10.1002/ADHM.201600263

Abstract: Targeted nanomaterials promise improved therapeutic efficacy, however their application in nanomedicine is limited due to complexities associated with protein conjugations to synthetic nanocarriers. A facile method to generate actively targeted nanomaterials is developed and exemplified using polyethylene glycol (PEG)-functional nanostructures coupled to a bispecific antibody (BsAb) with dual specificity for methoxy PEG (mPEG) epitopes and cancer targets such as epidermal growth factor receptor (EGFR). The EGFR-mPEG BsAb binds with high affinity to recombinant EGFR (KD : 1 × 10(-9) m) and hyperbranched polymer (HBP) consisting of mPEG (KD : 10 × 10(-9) m) and demonstrates higher avidity for HBP compared to linear mPEG. The binding of BsAb-HBP bioconjugate to EGFR on MDA-MB-468 cancer cells is investigated in vitro using a fluorescently labeled polymer, and in in vivo xenograft models by small animal optical imaging. The antibody-targeted nanostructures show improved accumulation in tumor cells compared to non-targeted nanomaterials. This demonstrates a facile approach for tuning targeting ligand density on nanomaterials, by modulating surface functionality. Antibody fragments are tethered to the nanomaterial through simple mixing prior to administration to animals, overcoming the extensive procedures encountered for developing targeted nanomedicines.

Purification of Fab fragments from a monoclonal antibody papain digest by Gradiflow electrophoresis

Publisher: Elsevier BV

Date: 12-2003

DOI: 10.1016/J.PEP.2003.07.005

Australia and New Zealand renal gene panel testing in routine clinical practice of 542 families

Publisher: Springer Science and Business Media LLC

Date: 04-03-2021

DOI: 10.1038/S41525-021-00184-X

Abstract: Genetic testing in nephrology clinical practice has moved rapidly from a rare specialized test to routine practice both in pediatric and adult nephrology. However, clear information pertaining to the likely outcome of testing is still missing. Here we describe the experience of the accredited Australia and New Zealand Renal Gene Panels clinical service, reporting on sequencing for 552 in iduals from 542 families with suspected kidney disease in Australia and New Zealand. An increasing number of referrals have been processed since service inception with an overall diagnostic rate of 35%. The likelihood of identifying a causative variant varies according to both age at referral and gene panel. Although results from high throughput genetic testing have been primarily for diagnostic purposes, they will increasingly play an important role in directing treatment, genetic counseling, and family planning.

Biosensing made easy with PEG-targeted bi-specific antibodies

Publisher: Royal Society of Chemistry (RSC)

Date: 2016

DOI: 10.1039/C6CC01916A

Abstract: Whilst recent advances in nanotechnology have yielded many new biosensing capabilities, innovative biological attachment and detection modalities remain relatively underdeveloped.

Preparation of optimized lipid-coated calcium phosphate nanoparticles for enhanced in vitro gene delivery to breast cancer cells

Publisher: Royal Society of Chemistry (RSC)

Date: 2015

DOI: 10.1039/C5TB00912J

Abstract: The optimized lipid coated calcium phosphate nanoparticles more efficiently deliver functional siRNA and inhibit the cancer cell growth, in comparison with the commercial transfection agent Oligofactamine TM .

Perfusion culture of Chinese Hamster Ovary cells for bioprocessing applications.

Publisher: Informa UK Limited

Date: 29-11-2022

DOI: 10.1080/07388551.2021.1998821

Abstract: Much of the biopharmaceutical industry's success over the past 30 years has relied on products derived from Chinese Hamster Ovary (CHO) cell lines. During this time, improvements in mammalian cell cultures have come from cell line development and process optimization suited for large-scale fed-batch processes. Originally developed for high cell densities and sensitive products, perfusion processes have a long history. Driven by high volumetric titers and a small footprint, perfusion-based bioprocess research has regained an interest from academia and industry. The recent pandemic has further highlighted the need for such intensified biomanufacturing options. In this review, we outline the technical history of research in this field as it applies to biologics production in CHO cells. We demonstrate a number of emerging trends in the literature and corroborate these with underlying drivers in the commercial space. From these trends, we speculate that the future of perfusion bioprocesses is bright and that the fields of media optimization, continuous processing, and cell line engineering hold the greatest potential. Aligning in its continuous setup with the demands for Industry 4.0, perfusion biomanufacturing is likely to be a hot topic in the years to come.

Retooling phage display with electrohydrodynamic nanomixing and nanopore sequencing

Publisher: Royal Society of Chemistry (RSC)

Date: 2019

DOI: 10.1039/C9LC00978G

Abstract: High throughput screening of phage display libraries for target binding molecules using electrohydrodynamic nanomixing and nanopore sequencing.

Analysis of coagulation factor IX in bioreactor cell culture medium predicts yield and quality of the purified product

Publisher: Cold Spring Harbor Laboratory

Date: 03-06-2020

DOI: 10.1101/2020.06.03.131177

Abstract: Coagulation factor IX (FIX) is a highly complex post-translationally modified human serum glycoprotein and a high-value biopharmaceutical. The quality of recombinant FIX (rFIX), especially complete γ-carboxylation, is critical for rFIX clinical efficacy. Changes in bioreactor operating conditions can impact rFIX production and occupancy and structure of rFIX post-translational modifications (PTMs). We hypothesized that monitoring the bioreactor cell culture supernatant with Data Independent Acquisition Mass Spectrometry (DIA-MS) proteomics would allow us to predict product yield and quality after purification. With the goal of optimizing rFIX production, we developed a suite of MS proteomics analytical methods and used these to investigate changes in rFIX yield, γ-carboxylation, other PTMs, and host cell proteins during bioreactor culture and after purification. Our methods provided a detailed overview of the dynamics of site-specific PTM occupancy and abundance on rFIX during production, which accurately predicted the efficiency of purification and the quality of the purified product from different culture conditions. In addition, we identified new PTMs in rFIX, some of which were near the GLA domain and could impact rFIX GLA-dependent purification efficiency and protein function. The workflows presented here are applicable to other biologics and expression systems, and should aid in the optimization and quality control of upstream and downstream bioprocesses.

Innovative Therapeutic Strategies for Effective Treatment of Brain Metastases

Publisher: MDPI AG

Date: 14-03-2019

DOI: 10.3390/IJMS20061280

Abstract: Brain metastases are the most prevalent of intracranial malignancies. They are associated with a very poor prognosis and near 100% mortality. This has been the case for decades, largely because we lack effective therapeutics to augment surgery and radiotherapy. Notwithstanding improvements in the precision and efficacy of these life-prolonging treatments, with no reliable options for adjunct systemic therapy, brain recurrences are virtually inevitable. The factors limiting intracranial efficacy of existing agents are both physiological and molecular in nature. For ex le, heterogeneous permeability, abnormal perfusion and high interstitial pressure oppose the conventional convective delivery of circulating drugs, thus new delivery strategies are needed to achieve uniform drug uptake at therapeutic concentrations. Brain metastases are also highly adapted to their microenvironment, with complex cross-talk between the tumor, the stroma and the neural compartments driving speciation and drug resistance. New strategies must account for resistance mechanisms that are frequently engaged in this milieu, such as HER3 and other receptor tyrosine kinases that become induced and activated in the brain microenvironment. Here, we discuss molecular and physiological factors that contribute to the recalcitrance of these tumors, and review emerging therapeutic strategies, including agents targeting the PI3K axis, immunotherapies, nanomedicines and MRI-guided focused ultrasound for externally controlling drug delivery.

Biological activity and metabolic clearance of recombinant human follicle stimulating hormone produced in Sp2/0 myeloma cells

Publisher: Springer Science and Business Media LLC

Date: 06-1996

DOI: 10.1007/BF02215667

Purification of recombinant human growth hormone from CHO cell culture supernatant by Gradiflow preparative electrophoresis technology

Publisher: Elsevier BV

Date: 11-2003

DOI: 10.1016/J.PEP.2003.07.002

Comparison and evaluation of immobilization methods for preparing bacterial probes using acidophilic bioleaching bacteria Acidithiobacillus thiooxidans for AFM studies

Publisher: Elsevier BV

Date: 07-2014

DOI: 10.1016/J.MIMET.2014.04.004

Abstract: We evaluated different strategies for constructing bacterial probes for atomic force microscopy studies of bioleaching Acidithiobacillus thiooxidans interacting with pyrite mineral surfaces. Of three available techniques, the bacterial colloidal probe technique is the most reliable and provides a versatile platform for quantifying true interactive forces between bioleaching microorganisms and mineral surfaces.

Comparison of the efficiency of Moloney Murine Leukaemia Virus (M-MuLV) reverse transcriptase, RNase H^--M-MuLV reverse transcriptase and Avian Myeloblastoma Leukaemia Virus (AMV) reverse transcriptase for the amplification of human immunoglobulin genes

Publisher: Springer Science and Business Media LLC

Date: 1998

DOI: 10.1023/A:1008871608947

Safety of biologics therapy: Monoclonal antibodies, cytokines, fusion proteins, hormones, enzymes, coagulation proteins, vaccines, botulinum toxins

Publisher: Informa UK Limited

Date: 05-07-2017

DOI: 10.1080/19420862.2017.1343709

Nanoyeast and Other Cell Envelope Compositions for Protein Studies and Biosensor Applications

Publisher: American Chemical Society (ACS)

Date: 04-11-2016

DOI: 10.1021/ACSAMI.6B09263

Multifunctional lipid-coated calcium phosphate nanoplatforms for complete inhibition of large triple negative breast cancer via targeted combined therapy

Publisher: Elsevier BV

Date: 09-2019

DOI: 10.1016/J.BIOMATERIALS.2019.119232

Abstract: Combined and targeted therapy have been extensively employed to achieve more effective elimination of tumor tissues. In this study, biocompatible multifunctional lipid-coated calcium phosphate nanoparticles (LCP NPs) were designed and constructed as an efficient targeted delivery system for combined gene hotothermal therapy to inhibit growth of the triple negative breast tumor (MDA-MB-468) in vitro and in vivo. LCP NPs were functionalized with a bispecific antibody (BsAb) via non-covalent bond specific for methoxy group of PEG (mPEG) on the particle surface. This BsAb is also able to target epidermal growth factor receptor (EGFR) expressed on MDA-MB-468 cells. Such LCP-BsAb NPs loaded with Cell Death (CD)-siRNA and indocyanine green (ICG) were efficiently taken up by MDA-MB-468 cells, significantly inducing cell apoptosis and synergistically suppressing cell proliferation upon irradiation of 808 nm near-infrared laser. These targeted multifunctional LCP NPs more efficiently accumulated in the tumor tissue. The combined RNAi (CD-siRNA) and photothermal (ICG) therapy using the targeted LCP NPs nearly eliminated both small tumors (∼100 mm

Targeted Nanomaterials: Overcoming Instability of Antibody‐Nanomaterial Conjugates: Next Generation Targeted Nanomedicines Using Bispecific Antibodies (Adv. Healthcare Mater. 16/2016)

Publisher: Wiley

Date: 08-2016

DOI: 10.1002/ADHM.201670084

Engineering death resistance in CHO cells for improved perfusion culture

Publisher: Informa UK Limited

Date: 23-06-2022

DOI: 10.1080/19420862.2022.2083465

Quantifying adhesion of acidophilic bioleaching bacteria to silica and pyrite by atomic force microscopy with a bacterial probe

Publisher: Elsevier BV

Date: 03-2014

DOI: 10.1016/J.COLSURFB.2013.11.047

Abstract: The adhesion of acidophilic bacteria to mineral surfaces is an important phenomenon in bioleaching processes. In this study, functionalized colloidal probes covered by bioleaching bacterial cells (Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans) were developed and used to sense specific adhesion forces to a silica surface and a pyrite surface in various solutions. Experimentally, recorded retraction curves of A. thiooxidans revealed sawtooth features that were in good agreement with the wormlike chain model, while that of L. ferrooxidans exhibited stair-step separation. The magnitudes of adhesion forces and snap-off distances were strongly influenced by the ionic strength and pH. Macroscopic surface properties including hydrophobicity and surface potential for bacterial cells and substrata were measured by a sessile drop method and microelectrophoresis. The ATR-FTIR spectra indicated the presence of different types of biopolymers on two strains of bacteria.

Expression and characterisation of recombinant human CD48 and isolation of a human anti-CD48 monoclonal antibody by phage display

Publisher: Wiley

Date: 14-03-2005

DOI: 10.1002/JCTB.1238

Studies on regenerating liver and hepatoma plasma membranes—i. lipid and protein composition

Publisher: Elsevier BV

Date: 1988

DOI: 10.1016/0020-711X(88)90100-0

Abstract: 1. Plasma membranes were isolated from normal liver, Morris hepatoma 7288C and regenerating liver, 6, 15, 24, and 48 hr after partial hepatectomy. 2. The cholesterol hospholipid ratio was lower in regenerating liver 6 hr after partial hepatectomy (0.51) compared to the sham control (0.68), returning to normal after 15 hr. This was accompanied by a small increase in palmitic acid (16:0). There were no other changes in the lipid composition in regenerating hepatocytes in the first 48 hr after partial hepatectomy. 3. Analysis of lipid composition showed a higher cholesterol hospholipid ratio in the hepatoma plasma membrane compared to normal liver accompanied by an increase in saturation of the fatty acyl groups of the phospholipids. There were also significant changes in the phospholipid classes. 4. There was no change in the two-dimensional electrophoretic profile of membrane proteins in the early stages of liver regeneration, however hepatoma membranes showed significant differences in protein profile. 5. These changes in the lipid composition of the hepatoma plasma membrane would have the effect of decreasing the average fluidity of the membrane and together with the changes in protein composition may be significant in the altered growth of the hepatoma. Changes in the lipid composition of the hepatocyte plasma membrane early in liver regeneration may reflect the onset of renewed cell ision.

A method for rapid, ligation-independent reformatting of recombinant monoclonal antibodies

Publisher: Elsevier BV

Date: 03-2010

DOI: 10.1016/J.JIM.2010.02.001

Abstract: Recombinant monoclonal antibodies currently dominate the protein biologics marketplace. The path from target antigen discovery and screening, to a recombinant therapeutic antibody can be time-consuming and laborious. We describe a set of expression vectors, termed mAbXpress, that enable rapid and sequence-independent insertion of antibody variable regions into human constant region backbones. This method takes advantage of the In Fusion cloning system from Clontech, which allows ligation-free, high-efficiency insertion of the variable region cassette without the addition of extraneous amino acids. These modular vectors simplify the antibody reformatting process during the preliminary evaluation of therapeutic or diagnostic candidates. The resulting constructs can be used directly for transient or lifiable, stable expression in mammalian cells. The effectiveness of this method was demonstrated by the creation of a functional, fully human anti-human CD83 monoclonal antibody.

Beyond Antibodies: Development of a Novel Protein Scaffold Based on Human Chaperonin 10

Publisher: Springer Science and Business Media LLC

Date: 22-11-2016

DOI: 10.1038/SREP37348

Abstract: Human Chaperonin 10 (hCpn10) was utilised as a novel scaffold for presenting peptides of therapeutic and diagnostic significance. Molecular dynamic simulations and protein sizing analyses identified a peptide linker (P1) optimal for the formation of the quarternary hCpn10 heptamer structure. hCpn10 scaffold displaying peptides targeting Factor VIIa (CE76 -P1 ) and CD44 (CP7) were expressed in E. coli . Functional studies of CE76 -P1 indicated nanomolar affinity for Factor VIIa (3 nM) similar to the E-76 peptide (6 nM), with undetectable binding to Factor X. CE76 -P1 was a potent inhibitor of FX activity (via inhibition of Factor VIIa) and prolonged clot formation 4 times longer than achieved by E-76 peptide as determined by prothrombin time (PT) assays. This improvement in clotting function by CE76 -P1 , highlights the advantages of a heptamer-based scaffold for improving avidity by multiple peptide presentation. In another ex le of hCPn10 utility as a scaffold, CP7 bound to native CD44 overexpressed on cancer cells and bound rCD44 with high affinity (K D 9.6 nM). The ability to present various peptides through substitution of the hCpn10 mobile loop demonstrates its utility as a novel protein scaffold.

Biologics and the emergence of biosimilars: Innovation driving global opportunity

Publisher: Wiley

Date: 09-06-2011

DOI: 10.1002/JCTB.2684

Production and characterisation of recombinant human chaperonin 10 for treatment of inflammatory disease

Publisher: Elsevier BV

Date: 10-2015

DOI: 10.1016/J.PROCBIO.2015.06.022

Increase in synthesis of human monoclonal antibodies by transfected Sp2/0 myeloma mouse cell line under conditions of microgravity

Publisher: Springer Science and Business Media LLC

Date: 2003

DOI: 10.1023/A:1025003800414

Abstract: Microgravity can influence cell growth and function. A transfected Sp2/0 myeloma cell line P3A2 producing a human IgG1 anti-TNFa monoclonal antibody was cultivated in static culture, spinner flasks and simulated microgravity using a rotating wall vessel bioreactor. Microgravity significantly decreased cell growth (from 1.7 x 10(6) to 7.9 x 10(5) cells/ml), but facilitated the synthesis of antibodies, (1.8, 1.3 and 0.5 microg of anti-TNFalpha hmAb per 10(6) viable cells for cells cultivated under microgravity, in spinner flasks and static cultures, respectively). The results suggest that microgravity could be applied to improve the specific productivity of cell lines producing potentially important therapeutic proteins.

Biosimilars approved for treatment of inflammatory rheumatological diseases

Publisher: Wiley

Date: 11-2016

DOI: 10.1111/1756-185X.13037

An EGFR targeting nanoparticle self assembled from a thermoresponsive polymer

Publisher: Wiley

Date: 11-09-2014

DOI: 10.1002/JCTB.4509

Cell-free pipeline for discovery of thermotolerant xylanases and endo -1,4-β-glucanases

Publisher: Elsevier BV

Date: 10-2017

DOI: 10.1016/J.JBIOTEC.2017.07.014

Abstract: The rapid expansion in the number of sequenced genomes and metagenomes provides an exceptional resource for mining of the enzymes with biotechnologically relevant properties. However, the majority of protein production and analysis methods are not sufficiently cost-efficient and scalable to experimentally verify the results of computational genomic mining. Here, we present a pipeline based on Leishmania tarentolae cell-free system that was used to characterize 30 putative thermostable endo-1,4-β-glucanases and xylanases identified in public genomic databases. In order to analyse the recombinant proteins without purification, novel high-throughput assays for glucanase and xylanase activities were developed. The assays rely on solubilisation of labelled particulate substrates performed in multiwell plates. Using this approach both acidophilic and thermophilic enzymes were identified. The developed approach enables rapid discovery of new biotechnologically useful enzymes.

Bridging the gap

Publisher: Informa UK Limited

Date: 09-2011

DOI: 10.4161/MABS.3.5.16968

Computational Identification of Antibody Epitopes on the Dengue Virus NS1 Protein.

Publisher: MDPI AG

Date: 10-04-2017

DOI: 10.3390/MOLECULES22040607

Differences in adhesion of A. thiooxidans and A. ferrooxidans on chalcopyrite as revealed by atomic force microscopy with bacterial probes

Publisher: Elsevier BV

Date: 06-2014

DOI: 10.1016/J.MINENG.2014.03.002

MIC-1, a novel macrophage inhibitory cytokine, is a divergent member of the TGF-β superfamily

Publisher: Proceedings of the National Academy of Sciences

Date: 14-10-1997

DOI: 10.1073/PNAS.94.21.11514

Abstract: Macrophages play a key role in both normal and pathological processes involving immune and inflammatory responses, to a large extent through their capacity to secrete a wide range of biologically active molecules. To identify some of these as yet not characterized molecules, we have used a subtraction cloning approach designed to identify genes expressed in association with macrophage activation. One of these genes, designated macrophage inhibitory cytokine 1 (MIC-1), encodes a protein that bears the structural characteristics of a transforming growth factor β (TGF-β) superfamily cytokine. Although it belongs to this superfamily, it has no strong homology to existing families, indicating that it is a ergent member that may represent the first of a new family within this grouping. Expression of MIC-1 mRNA in monocytoid cells is up-regulated by a variety of stimuli associated with activation, including interleukin 1β, tumor necrosis factor α (TNF-α), interleukin 2, and macrophage colony-stimulating factor but not interferon γ, or lipopolysaccharide (LPS). Its expression is also increased by TGF-β. Expression of MIC-1 in CHO cells results in the proteolytic cleavage of the propeptide and secretion of a cysteine-rich dimeric protein of M r 25 kDa. Purified recombinant MIC-1 is able to inhibit lipopolysaccharide -induced macrophage TNF-α production, suggesting that MIC-1 acts in macrophages as an autocrine regulatory molecule. Its production in response to secreted proinflammatory cytokines and TGF-β may serve to limit the later phases of macrophage activation.

Enhanced delivery of siRNA to triple negative breast cancer cells in vitro and in vivo through functionalizing lipid-coated calcium phosphate nanoparticles with dual target ligands

Publisher: Royal Society of Chemistry (RSC)

Date: 2018

DOI: 10.1039/C7NR08644J

Abstract: An optimized dual-target lipid-coated calcium phosphate-based nanoplatform efficiently delivers the drug/gene to triple-negative human breast tumor cells in vitro and in vivo .

A sensitive and specific ELISA detects methionine sulfoxide-containing apolipoprotein A-I in HDL

Publisher: Elsevier BV

Date: 03-2009

DOI: 10.1194/JLR.D800042-JLR200

Multiplexed SERS Detection of Soluble Cancer Protein Biomarkers with Gold–Silver Alloy Nanoboxes and Nanoyeast Single-Chain Variable Fragments

Publisher: American Chemical Society (ACS)

Date: 07-08-2088

DOI: 10.1021/ACS.ANALCHEM.8B02216

Abstract: Highly sensitive, multiplexed detection of soluble cancer protein biomarkers can facilitate early cancer screening as well as enable real-time monitoring of patients' sensitivity and resistance to therapy. Current technologies for detection of soluble cancer protein biomarkers, e.g., enzyme-linked immunosorbent assay, however, suffer from limited sensitivity, as well as the requirement of expensive monoclonal antibodies, which undergo the quality variability. Herein, we propose a sensitive, cheap, and robust surface-enhanced Raman scattering technology to detect a panel of soluble cancer protein biomarkers, including soluble programmed death 1 (sPD-1), soluble programmed death-ligand 1 (sPD-L1) and soluble epithermal growth factor receptor (sEGFR), which are related to disease progression and treatment efficacy. In this assay, gold-silver alloy nanoboxes that have strong Raman signal enhancement capability were used as plasmonic nanostructures to facilitate highly sensitive detection. In addition, nanoyeast single-chain variable fragments were utilized as mAb alternatives to allow specific and stable protein capture performance. We successfully detected sPD-1, sPD-L1, and sEGFR with a limit of detection of 6.17 pg/mL, 0.68 pg/mL, and 69.86 pg/mL, respectively. We further tested the detection of these three soluble cancer protein biomarkers in human serum and achieved recovery rates between 82.99% and 101.67%. We believe our novel platform that achieves sensitive, multiplexed, and specific detection of soluble cancer protein biomarkers could greatly benefit cancer treatment and improve patient outcome.

The application of emerging technologies in genomics and proteomics to drug development

Publisher: Wiley

Date: 03-2003

DOI: 10.1002/JPPR20033317

Production and characterization of specific monoclonal antibodies binding the Plasmodium falciparum diagnostic biomarker, histidine-rich protein 2

Publisher: Springer Science and Business Media LLC

Date: 18-07-2014

DOI: 10.1186/1475-2875-13-277

Wavelength-Dependent Fluorescent Immunosensors via Incorporation of Polarity Indicators near the Binding Interface of Antibody Fragments

Publisher: American Chemical Society (ACS)

Date: 22-05-2019

DOI: 10.1021/ACS.ANALCHEM.9B00445

Abstract: Herein, we describe a fluorescent immunosensor designed by incorporating an unnatural amino acid fluorophore into the binding site of an EGFR-specific antibody fragment, resulting in quantifiable EGFR-dependent changes in peak fluorescence emission wavelength. To date, immunosensor design strategies have relied on binding-induced changes in fluorescence intensity that are prone to excitation source fluctuations and s le-dependent noise. In this study, we used a rational design approach to incorporate a polarity indicator (Anap) into specific positions of an anti-EGFR single chain antibody to generate an emission wavelength-dependent immunosensor. We found that when incorporated within the topological neighborhood of the antigen binding interface, the Anap emission wavelength is blue-shifted by EGFR-binding in a titratable manner, up to 20 nm, with nanomolar detection limits. This approach could be applicable to other antibody/antigen combinations for integration into a wide range of assay platforms (including homogeneous, solid-phase assay, or microfluidic assays) for one-step protein quantification.

Fractionation of follicle stimulating hormone charge isoforms in their native form by preparative electrophoresis technology

Publisher: Elsevier BV

Date: 03-2006

DOI: 10.1016/J.JBIOTEC.2005.08.026

Abstract: Complex glycoprotein biopharmaceuticals, such as follicle stimulating hormone (FSH), erythropoietin and tissue plasminogen activator consist of a range of charge isoforms due to the extent of sialic acid capping of the glycoprotein glycans. Sialic acid occupies the terminal position on the oligosaccharide chain, masking the penultimate sugar residue, galactose from recognition and uptake by the hepatocyte asialoglycoprotein receptor. It is therefore well established that the more acidic charge isoforms of glycoprotein biopharmaceuticals have higher in vivo potencies than those of less acidic isoforms due to their longer serum half-life. Current strategies for manipulating glycoprotein charge isoform profile involve cell engineering or altering bioprocesss parameters to optimise expression of more acidic or basic isoforms, rather than downstream separation of isoforms. A method for the purification of a discrete range of bioactive recombinant human FSH (rhFSH) charge isoforms based on Gradiflowtrade mark preparative electrophoresis technology is described. Gradiflowtrade mark electrophoresis is scaleable, and incorporation into glycoprotein biopharmaceutical production bioprocesses as a potential final step facilitates the production of biopharmaceutical preparations of improved in vivo potency.

Recent Advances in the Generation of Antibody–Nanomaterial Conjugates

Publisher: Wiley

Date: 29-09-2018

DOI: 10.1002/ADHM.201700607

Abstract: Targeted nanomedicines have significantly changed the way new therapeutics are designed to treat disease. Central to successful therapeutics is the ability to control the dynamics of protein-nanomaterial interactions to enhance the therapeutic effect of the nanomedicine. The aim of this review is to illustrate the ersity and versatility of the conjugation approaches involved in the synthesis of antibody-nanoparticle conjugates, and highlight significant new advances in the field of bioconjugation. Such nanomedicines have found utility as both advanced therapeutic agents, as well as more complex imaging contrast agents that can provide both anatomical and functional information of diseased tissue. While such conjugates show significant promise as next generation targeted nanomedicines, it is recognized that there are in fact no clinically approved targeted therapeutics on the market. This fact is reflected upon within this review, and attempts are made to draw some reasoning from the complexities associated with the bioconjugation chemistry approaches that are typically utilized. Present trends, as well as future directions of next generation targeted nanomedicines are also discussed.

Monoclonal antibody‐targeted polymeric nanoparticles for cancer therapy – future prospects

Publisher: Wiley

Date: 31-10-2014

DOI: 10.1002/JCTB.4555

Attenuating apoptosis in Chinese hamster ovary cells for improved biopharmaceutical production

Publisher: Wiley

Date: 23-01-2020

DOI: 10.1002/BIT.27269

Abstract: Chinese hamster ovary (CHO) cells are the predominant host cell line for the production of biopharmaceuticals, a growing industry currently worth more than $188 billion USD in global sales. CHO cells undergo programmed cell death (apoptosis) following different stresses encountered in cell culture, such as substrate limitation, accumulation of toxic by-products, and mechanical shear, hindering production. Genetic engineering strategies to reduce apoptosis in CHO cells have been investigated with mixed results. In this review, a contemporary understanding of the real complexity of apoptotic mechanisms and signaling pathways is described followed by an overview of antiapoptotic cell line engineering strategies tested so far in CHO cells.

Functional domain analysis of SOX18 transcription factor using a single-chain variable fragment-based approach

Publisher: Informa UK Limited

Date: 16-04-2018

DOI: 10.1080/19420862.2018.1451288

Clonal selection of high producing, stably transfected HEK293 cell lines utilizing modified, high‐throughput FACS screening

Publisher: Wiley

Date: 28-03-2011

DOI: 10.1002/JCTB.2618

Isoelectric charge of recombinant human follicle-stimulating hormone isoforms determines receptor affinity and in vitro bioactivity.

Publisher: The Endocrine Society

Date: 1993

DOI: 10.1210/ENDO.132.1.8419133

Abstract: Recombinant human FSH (rhFSH) was obtained by expressing the human FSH alpha- and beta-subunit complementary DNAs in the chinese hamster ovary cell line. Isoforms of rhFSH were resolved into specific isoelectric (pI) fractions by chromatofocusing. rhFSH isoforms ranged from pI 3.0-5.5 with a modal value of pI 4.2. Analysis of the biological activity of specific pI isoforms of rhFSH was undertaken using both the rat granulosa cell aromatase (in vitro) bioassay and a RRA. More acidic isoforms (e.g. pI 3.5) showed significantly lower affinity (P < 0.05) for rat testicular FSH receptors than did the less acidic isoforms (e.g. pI 4.8). Consistent with the receptor binding affinity data, the more acidic fractions resulted in significantly less activation (P < 0.05) of rat granulosa cell aromatase activity, as measured by estrogen production, than did the less acidic isoforms. The observed bioactivities and their correlation with the pI values of the rhFSH isoforms are consistent with observations of differing bioactivities seen in both pituitary and urinary FSH isoforms. These results demonstrate that rhFSH, made in the chinese hamster ovary cell line, is both biologically active and has isoform profiles, and presumably carbohydrate structures, that closely resemble those seen in natural hFSH.

The effectiveness of different rat IgG subclasses as IgE‐blocking antibodies in the rat basophil leukaemia cell model

Publisher: Wiley

Date: 04-1999

DOI: 10.1046/J.1440-1711.1999.00801.X

Abstract: The degranulation of mast cells in an allergic response is initiated by the aggregation of high-affinity IgE receptors (Fc epsilon RI) by IgE and antigen. Recently it has been shown that such degranulation can be inhibited by cross-linking Fc epsilon RI and low-affinity IgG receptors (Fc gamma RII) which are also expressed by mast cells. The ability of various monoclonal antibodies to block the degranulation of rat basophil leukaemia (RBL) cells sensitized with IgE antidinitrophenyl (DNP) antibodies has been investigated. Sensitized cells were challenged with immune complexes formed using varying concentrations of antigen, and of both high- and low-valency antigen. It is reported here that rat IgG1 antibodies, which are associated in the rat with a Th1-type response, act as highly effective blocking antibodies over a wide concentration range. Rat IgG2a antibodies, which are associated with a Th2-type response, were able only to inhibit degranulation when immune complexes were formed with very low concentrations of high-valency antigen (DNP32-HSA). Under these conditions, some inhibitory activity was seen with high-affinity murine IgA anti-DNP but not with low-affinity rat IgG2b anti-DNP antibody-containing immune complexes. In addition to this inhibitory activity, IgG2a antibodies were shown to be capable of inducing degranulation of cells via unoccupied Fc epsilon RI. These results demonstrate that blocking activity may arise via both inhibitory receptors and by masking of antigen.

Disease-specific, neurosphere-derived cells as models for brain disorders

Publisher: The Company of Biologists

Date: 28-10-2010

DOI: 10.1242/DMM.005447

Abstract: There is a pressing need for patient-derived cell models of brain diseases that are relevant and robust enough to produce the large quantities of cells required for molecular and functional analyses. We describe here a new cell model based on patient-derived cells from the human olfactory mucosa, the organ of smell, which regenerates throughout life from neural stem cells. Olfactory mucosa biopsies were obtained from healthy controls and patients with either schizophrenia, a neurodevelopmental psychiatric disorder, or Parkinson’s disease, a neurodegenerative disease. Biopsies were dissociated and grown as neurospheres in defined medium. Neurosphere-derived cell lines were grown in serum-containing medium as adherent monolayers and stored frozen. By comparing 42 patient and control cell lines we demonstrated significant disease-specific alterations in gene expression, protein expression and cell function, including dysregulated neurodevelopmental pathways in schizophrenia and dysregulated mitochondrial function, oxidative stress and xenobiotic metabolism in Parkinson’s disease. The study has identified new candidate genes and cell pathways for future investigation. Fibroblasts from schizophrenia patients did not show these differences. Olfactory neurosphere-derived cells have many advantages over embryonic stem cells and induced pluripotent stem cells as models for brain diseases. They do not require genetic reprogramming and they can be obtained from adults with complex genetic diseases. They will be useful for understanding disease aetiology, for diagnostics and for drug discovery.

Insights into the interfacial structure–function of poly(ethylene glycol)-decorated peptide-stabilised nanoscale emulsions

Publisher: Royal Society of Chemistry (RSC)

Date: 2017

DOI: 10.1039/C7SM01614J

Abstract: This work provides describes the presentation and accessibility of functional moieties, such as targeting ligands, on peptide-stabilised nanocarrier emulsions.

Selection of antibodies to transiently expressed membrane proteins using phage display

Publisher: Springer New York

Date: 2018

DOI: 10.1007/978-1-4939-8648-4_10

Abstract: Cell membrane proteins serve as attractive targets for biopharmaceutical development in addition to gauging their fundamental process in a biological system. Approximately 38% of the entire genome codes for plasma membrane proteins however the discovery and development of antibody binders to such targets are a technical challenge. Methods to raise binders against such targets by cloning and expressing soluble extracellular regions have been met with limited success due to the loss of critical epitopes, with the resulting antibodies failing to bind to their target in its native conformation. This chapter outlines a "cell based biopanning" method in order to isolate antibodies against membrane proteins in their native conformation using transiently expressed, GFP-tagged target proteins. This method overcomes the limitations of non-specific binding of phage to the cells, abundance of irrelevant antigens on the cell surface, while retaining the native structure of the antigen on the cell surface.

Targeting mesothelin receptors with drugloaded bacterial nanocells suppresses human mesothelioma tumour growth in mouse xenograft models

Publisher: Public Library of Science (PLoS)

Date: 23-10-2017

DOI: 10.1371/JOURNAL.PONE.0186137

Cloning and expression of human V-genes derived from phage display libraries as fully assembled human anti-TNFα monoclonal antibodies

Publisher: Elsevier BV

Date: 03-1997

DOI: 10.1016/S1380-2933(96)00058-9

Abstract: With the advent of phage antibody libraries, access to completely human antibody fragments is feasible, either by direct selection from human antibody libraries, or by guided selection. After selection, Fabs and scFvs may need to be expressed as complete antibodies in mammalian cells for further characterisation, or if effector functions are required. To rebuild and express the human anti-TNF alpha antibody Fab-P3A2 (isolated as a Fab fragment from phage display libraries by guided selection) as a fully assembled, functional human antibody (gamma-1, lambda) in Sp2/0 myeloma cells, and to perform preliminary characterisation studies of the secreted IgG1 molecule. A further objective was to investigate the kinetics of human antibody production and the stability of antibody secretion in transfectomas cultured in various media formulations. A tripartite strategy was employed for cloning heavy chain gene (VH)-P3 and light chain gene V lambda-A2-C lambda into mammalian cell expression vectors p alpha Lys-30 and p alpha Lys-17 respectively. The cell line P3A2.B5 was isolated after co-transfection of Sp2/0 mouse myelomas with the constructs, expanded and weaned into a protein free medium. Fully assembled Ig-P3A2 antibody was purified by Protein A affinity chromatography and characterised with respect to size of antibody chains, and affinity for human TNF alpha. Stability of secretion was investigated by extended serial sub-culture and analysis of P3A2.B5 sub-clones. Strategies of media enrichment were tested for any effect on antibody productivity by selected P3A2.B5 sub-clones. The cell line P3A2.B5 secreted an assembled, human antibody Ig-P3A2, with heavy and light chains of molecular weight 55 and 28 KD respectively. Equilibrium capture studies showed Ig-P3A2 to have a dissociation constant of approximately 1.5 x 10(-8) M. The mean specific productivity of the cell line increased from 1.2 pg/cell/day to 7.8 pg/cell/day by a combination of medium enrichment and serum reduction. Prolonged serial sub-culture of P3A2.B5 showed the cell line to be unstable with respect to antibody secretion. We have outlined a method for expression of human V genes as assembled antibodies in Sp2/0 myeloma cells. A cloning strategy for the stable expression of scFv or Fab genes isolated from phage display libraries as assembled human antibodies of the IgGl subclass in Sp2/0 myeloma cells has been described. For maximising specific productivity of antibody-producing cell lines, supplementation of culture media with glucose, glutamine and amino acids increases antibody yield significantly compared to that in conventional media, indicating the latter is stoichiometrically limiting for production purposes.

The macrophage-biomaterial interface: A proteomic analysis of the conditioned medium environment

Publisher: Wiley

Date: 11-02-2008

DOI: 10.1002/JCTB.1854

Studies on regenerating liver and hepatoma plasma membranes-ii. membrane fluidity and enzyme activity

Publisher: Elsevier BV

Date: 1988

DOI: 10.1016/0020-711X(88)90101-2

Abstract: 1. Rat hepatocyte plasma membranes isolated from Morris hepatoma 7288C, normal and regenerating liver were labelled with the fluorescent probe 1,6-diphenyl-1,3,5-hexatriene. 2. Steady-state fluorescence polarisation measurements indicated an increased fluidity of the membranes in the early stages of regeneration, returning to normal levels after 48 hr. 3. There was a decrease in hepatoma plasma membrane fluidity compared to normal hepatocytes. Changes in fluorescence polarisation with temperature (Arrhenius studies) indicate an increase in the lower critical temperature for the membrane lipid thermotropic transition of hepatoma compared to normal liver plasma membranes. 4. These changes in membrane lipid fluidity alter the activation of some intrinsic and extrinsic membrane bound enzymes.

Desensitization of adenylate cyclase and cyclic AMP flux during the early stages of liver regeneration

Publisher: Wiley

Date: 07-1988

DOI: 10.1002/JCP.1041360111

Abstract: Liver regeneration is controlled by a complex network of interactions between hormones, growth factors, and a variety of hepatotrophic factors. Transient increases in cAMP in the early stages of liver regeneration that are necessary for DNA synthesis and subsequent mitosis have been reported however, studies on the mechanisms that control cellular cAMP levels during liver regeneration, namely adenylate cyclase activity, cAMP-dependent phosphodiesterase activity, and cAMP efflux from the cell, have been generally incomplete. In this study we have shown that although there are three peaks in intracellular cAMP levels in the first 24 hours after partial hepatectomy, the adenylate cyclase activity stimulated by glucagon, prostaglandin E2, adrenaline, and fluoride in vitro decreases with time. KD and BMAX of hepatocyte glucagon and beta receptors were similar to the sham controls. Our results are consistent with a mixed homologous/heterologous desensitization of the adenylate cyclase system. There was also a loss of cAMP-dependent phosphodiesterase activity after partial hepatectomy. We speculate that even though the hormone-stimulated adenylate cyclase system has been desensitized, the system retains the ability to respond to the transient pulses of the variety of hormones secreted after partial hepatectomy and thus raise the intracellular concentration of cAMP. The decrease in cAMP-dependent phosphodiesterase may be necessary to prevent rapid breakdown of cAMP.

Advances in Drug Delivery

Publisher: Wiley

Date: 04-06-2015

DOI: 10.1002/JCTB.4689

BioPEGylation of Polyhydroxyalkanoates: Influence on Properties and Satellite-Stem Cell Cycle

Publisher: American Chemical Society (ACS)

Date: 29-08-2008

DOI: 10.1021/BM800418E

Abstract: The addition of poly(ethylene glycol), PEG, to bioprocessing systems producing polyhydroxyalkanoates (PHAs), has been reported as a means of their molecular weight control and can also support bioPEGylation, resulting in hybrids with hiphillic properties. However, the study of such natural-synthetic hybrids of PHA-b-PEG is still in its infancy. In this study, we report the influence of bioPEGylation of polyhydroxyoctanoate (PHO) on its physiochemical, material, and biological properties. Consistent with previous studies, bioPEGylation with diethylene glycol (DEG) showed a significant reduction in PHA molecular weight (57%). In comparison to solvent cast films of PHO, PHO-b-DEG films possessed a noticeable X-ray diffraction peak at 9.82 degrees and increased Young's modulus of 11 Gpa (83%). Potential biocompatibility was investigated by measuring the early phase of apoptosis in myoblastic satellite-stem cells (C2C12). Comparative analysis of cell proliferation and progression in the presence of the mcl-PHA and its hybrid showed that the latter induced significant cell cycle progression: the first time a biomaterial has been shown to do so. Microtopographies of the film surfaces demonstrated that these differences were not due to changes in surface morphology both polymers possessed average surface rugosities of 1.4 +/- 0.2 microm. However, a slight decrease in surface hydrophobicity (3.5 +/- 0.9 degrees) due to the hydrophilic DEG may have exerted an influence. The results support the further study of bioPEGylated PHAs as potential biomaterials in the field of tissue engineering.

Analytical strategies for assessing comparability of biosimilars

Publisher: Wiley

Date: 26-04-2011

DOI: 10.1002/JCTB.2629

Guiding the selection of human antibodies from phage display repertoires to a single epitope of an antigen

Publisher: Springer Science and Business Media LLC

Date: 09-1994

DOI: 10.1038/NBT0994-899

Abstract: We have developed a strategy for guiding the selection of human antibody fragments from phage display repertoires to a single epitope of an antigen, using rodent monoclonal antibodies as a template. Thus the heavy chain of a rodent antibody (MAb32) directed against human tumor necrosis factor alpha (TNF alpha) was cloned and paired as a template chain with a repertoire of human light chains for display as Fab fragments on filamentous phage. The phage were selected by binding to the antigen. The selected human light chains were in turn paired with a repertoire of human heavy chains displayed on phage, and the phage selected again. The isolated phage displaying human antibody fragments binding to TNF alpha also bound to a peptide comprising the N-terminal region of TNF alpha as with MAb32. One of the human Fab fragments was recloned for expression as a glycosylated human antibody in mammalian cells: Binding to TNF alpha could be competed with MAb32 or with anti-serum to the peptide, indicating the same epitope. The human antibody was found to have a binding affinity (Kd = 15 nM) similar to MAb32 (Kd = 26 nM). The process contrasts with existing means of "humanizing" rodent monoclonal antibodies in that the antibodies derived are completely human.

Targeting membrane proteins for antibody discovery using phage display

Publisher: Springer Science and Business Media LLC

Date: 18-05-2016

DOI: 10.1038/SREP26240

Abstract: A critical factor in the successful isolation of new antibodies by phage display is the presentation of a correctly folded antigen. While this is relatively simple for soluble proteins which can be purified and immobilized onto a plastic surface, membrane proteins offer significant challenges for antibody discovery. Whole cell panning allows presentation of the membrane protein in its native conformation, but is complicated by a low target antigen density, high background of irrelevant antigens and non-specific binding of phage particles to cell surfaces. The method described here uses transient transfection of alternating host cell lines and stringent washing steps to address each of these limitations. The successful isolation of antibodies from a naive scFv library is described for three membrane bound proteins human CD83, canine CD117 and bat CD11b.

In focus: Stem cell and tissue engineering applications in regenerative medicine

Publisher: Wiley

Date: 11-03-2008

DOI: 10.1002/JCTB.1933

Isolation of serotype-specific antibodies against dengue virus non-structural protein 1 using phage display and application in a multiplexed serotyping assay

Publisher: Public Library of Science (PLoS)

Date: 06-07-2017

DOI: 10.1371/JOURNAL.PONE.0180669

Evidence of heterogeneity in the antibody response against the platelet antigen 3a; Recognition of an 11-mer peptide carrying the HPA-3a polymorphic determinant

Publisher: Wiley

Date: 08-03-2009

DOI: 10.1111/J.1423-0410.2008.01146.X

Abstract: The immune processes involved in the development of alloantibodies against the human platelet antigens in alloimmune disorders remain unclear. Antibody recognition of the platelet antigens on their respective platelet glycoproteins has been shown to be dependent on glycoprotein conformation. Furthermore, the post-translational modification of glycoproteins adds complexity to the alloantigenic determinants. Nine anti-HPA-3a sera along with several control sera were tested for reactivity to an 11-mer peptide straddling the HPA-3a/b polymorphism. Sera found to specifically recognize the 3a peptide were further assessed by platelet pre-exposure and immunoblotting. Three of the nine antisera were found to specifically recognize an 11-mer synthetic 3a peptide by ELISA. Further analysis of all anti-HPA-3a sera by Western blot showed that only those reactive to the 3a peptide were able to bind both reduced and non-reduced GPIIb. The results presented in this study provide the first known evidence for the identification of an antibody population capable of recognizing a linear and non-glycosylated form of the HPA-3a epitope.

A concise review of nanoscopic aspects of bioleaching bacteria–mineral interactions

Publisher: Elsevier BV

Date: 10-2014

DOI: 10.1016/J.CIS.2014.08.005

Abstract: Bioleaching is a technology for the recovery of metals from minerals by means of microorganisms, which accelerate the oxidative dissolution of the mineral by regenerating ferric ions. Bioleaching processes take place at the interface of bacteria, sulfide mineral and leaching solution. The fundamental forces between a bioleaching bacterium and mineral surface are central to understanding the intricacies of interfacial phenomena, such as bacterial adhesion or detachment from minerals and the mineral dissolution. This review focuses on the current state of knowledge in the colloidal aspect of bacteria-mineral interactions, particularly for bioleaching bacteria. Special consideration is given to the microscopic structure of bacterial cells and the atomic force microscopy technique used in the quantification of fundamental interaction forces at nanoscale.

Chemogenetic Manipulations of Ventral Tegmental Area Dopamine Neurons Reveal Multifaceted Roles in Cocaine Abuse

Publisher: Cold Spring Harbor Laboratory

Date: 26-02-2018

DOI: 10.1101/246595

Abstract: Ventral tegmental area (VTA) dopamine (DA) neurons perform erse functions in motivation and cognition, but their precise roles in addiction-related behaviors are still debated. Here, we targeted VTA DA neurons for bidirectional chemogenetic modulation during specific tests of cocaine reinforcement, demand, and relapse-related behaviors, querying the roles of DA neuron inhibitory and excitatory G-protein signaling in these processes. Designer receptor stimulation of Gq-, but not Gs-signaling in DA neurons enhanced cocaine seeking via functionally distinct projections to forebrain limbic regions. In contrast, engaging inhibitory Gi/o signaling in DA neurons blunted cocaine’s reinforcing and priming effects, reduced stress-potentiated reinstatement, and altered cue-induced cocaine seeking strategy, but not the motivational impact of cocaine cues per se. Results demonstrate that DA neurons play several distinct roles in cocaine seeking, depending on behavioral context, G-protein signaling, and DA neuron efferent target, highlighting their multifaceted roles in addiction. G-protein coupled receptors are crucial modulators of VTA dopamine neuron activity, but how metabotropic signaling impacts dopamine’s complex roles in reward and addiction is poorly understood. Here, we bidirectionally modulate dopamine neuron G-protein signaling with DREADDs during a variety of cocaine seeking behaviors, revealing nuanced, pathway-specific roles in cocaine reward, effortful seeking, and relapse-like behaviors. Gq- and Gs-stimulation activated dopamine neurons, but only Gq stimulation robustly enhanced cocaine seeking. Gi/o inhibitory signaling altered the response strategy employed during cued reinstatement, and reduced some, but not all types of cocaine seeking. Results show that VTA dopamine neurons modulate numerous distinct aspects of cocaine addiction- and relapse-related behaviors, and indicate potential new approaches for intervening in these processes to treat addiction.

Material surfaces affect the protein expression patterns of human macrophages: A proteomics approach

Publisher: Wiley

Date: 27-10-2007

DOI: 10.1002/JBM.A.30967

Abstract: Monocyte-derived macrophages (MDM) are key inflammatory cells and are central to the foreign body response to implant materials. MDM have been shown to exhibit changes in actin cytoskeleton, multinucleation, cell size, and function in response to small alterations in polycarbonate-urethane (PCNU) surface chemistry. Although PCNU chemistry has an influence on de novo protein synthesis, no assessments of the protein expression profiles of MDM have yet been reported. The rapid emerging field of expression proteomics facilitates the study of changes in cellular protein profiles in response to their microenvironment. The current study applied proteomic techniques, 2-dimensional electrophoresis (2-DE) combined with MALDI-ToF (matrix assisted laser desorption ionization-time of flight) mass spectrometry, to determine differences in MDM protein expression influenced by PCNU. Results indicated that MDM responded to material chemistry by modulation of structural proteins (i.e. actin, vimentin, and tubulin). Additionally, intracellular protein modulation which requires proteins responsible for trafficking (i.e. chaperone proteins) and protein structure modification (i.e. bond rearrangement and protein folding) were also altered. This study demonstrated for the first time that a proteomics approach was able to detect protein expression profile changes in MDM cultured on different material surfaces, forming the basis for utilizing further quantitative proteomics techniques that could assist in elucidation of the mechanisms involved in MDM-material interaction.

University Of Queensland

Location: Australia

View Organisation

Single Molecule Spectroscopy-guided Design Of Thermostable Industrial Enzymes

Start Date: 2012

End Date: 2014

Funder: Australian Research Council

Development Of Chaperonin 10-based Second Generation Biopharmaceuticals For Treatment Of Inflammatory Diseases

Start Date: 2008

End Date: 2011

Funder: Australian Research Council

Opioid Modulation Of Cue-Triggered 'Wanting' In Amygdala

Start Date: 2006

End Date: 2009

Funder: National Institute on Drug Abuse

The First Integrated Multimodal Assay For The Ultrasensitive Detection Of Dengue Contamination Of Blood

Start Date: 2012

End Date: 2014

Funder: Australian Research Council

VTA Glutamate And Orexin Involvement In Cue Reinstatement Of Drug Seeking

Start Date: 2010

End Date: 2012

Funder: National Institute on Drug Abuse

The Tissue Engineering Of Tissue Regeneration: Innovative Biomaterials For Tissue Regeneration

Start Date: 2003

End Date: 2006

Funder: Australian Research Council

Stem Cell-based Interface Tissue Engineering

Start Date: 2009

End Date: 2009

Funder: Australian Research Council

Safety Of Hendra Virus Anti-G Glycoprotein Monoclonal Antibody In Humans

Start Date: 2012

End Date: 2013

Funder: National Health and Medical Research Council

Role Of Ventral Pallidum Projection To VTA In Reinstatement Of Cocaine Seeking

Start Date: 2013

End Date: 2015

Funder: National Institute on Drug Abuse

Engineering Of Anti-platelet Antibodies For The Diagnosis And Therapy Of Infants With Bleeding Disorders

Start Date: 2002

End Date: 2004

Funder: Australian Research Council

Determination Of The Mechanisms Of Immune System Regulation Of Inflammation By The Human Protein, Chaperonin 10

Start Date: 2005

End Date: 2007

Funder: Australian Research Council

ARC Training Centre For Biopharmaceutical Innovation

Start Date: 2016

End Date: 2020

Funder: Australian Research Council

Targeting The Delivery Of Cytotoxic Agents To Tumour Cells Using Novel Minicells As Drug Delivery Vehicles And Engineered, Bispecific Antibodies

Start Date: 2011

End Date: 2014

Funder: Australian Research Council

Immune Polymeric Drugs For Prostate Cancer Therapy

Start Date: 2016

End Date: 2018

Funder: National Health and Medical Research Council

Hybrid Nanomaterials: Bispecific Antibody-targeted Polymers

Start Date: 2015

End Date: 2017

Funder: Australian Research Council

Linkage Projects - Grant ID: LP120100162

Start Date: 09-2012

End Date: 09-2015

Amount: $576,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP120100626

Start Date: 08-2012

End Date: 08-2015

Amount: $490,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP0986619

Start Date: 2009

End Date: 04-2010

Amount: $140,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP0883403

Start Date: 03-2010

End Date: 03-2013

Amount: $270,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP0349196

Start Date: 12-2003

End Date: 06-2007

Amount: $195,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP110200126

Start Date: 05-2012

End Date: 05-2015

Amount: $352,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP0221344

Start Date: 05-2002

End Date: 05-2006

Amount: $67,635.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP0560289

Start Date: 2005

End Date: 12-2010

Amount: $337,826.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP150100703

Start Date: 06-2016

End Date: 06-2019

Amount: $360,000.00

Funder: Australian Research Council

Industrial Transformation Training Centres - Grant ID: IC160100027

Start Date: 03-2017

End Date: 03-2023

Amount: $4,340,802.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP180100486

Start Date: 11-2019

End Date: 12-2022

Amount: $390,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE200100140

Start Date: 03-2020

End Date: 06-2021

Amount: $945,000.00

Funder: Australian Research Council