Hamsa Puthalakath

Semiquantitative Proteomics Enables Mapping of Murine Neutrophil Dynamics following Lethal Influenza Virus Infection

Publisher: The American Association of Immunologists

Date: 15-08-2019

DOI: 10.4049/JIMMUNOL.1900337

Abstract: Neutrophils are rapidly deployed innate immune cells, and excessive recruitment is causally associated with influenza-induced pathologic conditions. Despite this, the complete set of influenza lethality–associated neutrophil effector proteins is currently unknown. Whether the expression of these proteins is predetermined during bone marrow (BM) neutrophil maturation or further modulated by tissue compartment transitions has also not been comprehensively characterized at a proteome-wide scale. In this study, we used high-resolution mass spectrometry to map how the proteomes of murine neutrophils change comparatively across BM, blood, and the alveolar airspaces to deploy an influenza lethality–associated response. Following lethal influenza infection, mature neutrophils undergo two infection-dependent and one context-independent compartmental transitions. Translation of type I IFN–stimulated genes is first elevated in the BM, preceding the context-independent downregulation of ribosomal proteins observed in blood neutrophils. Following alveolar airspace infiltration, the bronchoalveolar lavage (BAL) neutrophil proteome is further characterized by a limited increase in type I IFN–stimulated and metal-sequestering proteins as well as a decrease in degranulation-associated proteins. An influenza-selective and dose-dependent increase in antiviral and lipid metabolism-associated proteins was also observed in BAL neutrophils, indicative of a modest capacity for pathogen response tuning. Altogether, our study provides new and comprehensive evidence that the BAL neutrophil proteome is shaped by BM neutrophil maturation as well as subsequent compartmental transitions following lethal influenza infection.

Absence of pro-survival A1 has no impact on inflammatory cell survival in vivo during acute lung inflammation and peritonitis

Publisher: Research Square Platform LLC

Date: 22-03-2021

DOI: 10.21203/RS.3.RS-333716/V1

Abstract: Inflammation is a natural defense mechanism of the body to protect against pathogens. It is induced by immune cells, such as macrophages and neutrophils, which are rapidly recruited to the site of infection, mediating host defense. The processes for eliminating inflammatory cells after pathogen clearance are critical in preventing sustained inflammation which can cause erse pathologies. During chronic inflammation, excessive and uncontrollable activity of the immune system can cause extensive tissue damage. New therapies aimed at preventing this over-activity of the immune system could have major clinical benefit. Here, we investigated the role of the pro-survival Bcl-2 family member A1 in the survival of inflammatory cells under normal and inflammatory conditions using murine models of lung and peritoneal inflammation. Despite the robust upregulation of A1 protein levels in wild-type cells upon induction of inflammation, the survival of inflammatory cells was not impacted in A1 deficient mice compared to wild-type controls. These findings indicate that A1 does not play a major role in immune cell homeostasis during inflammation and therefore does not constitute a therapeutic target for such morbidities.

Genetic defect in N-acetylglucosaminyltransferase I gene of a ricin-resistant baby hamster kidney mutant.

Publisher: Portland Press Ltd.

Date: 15-12-1998

DOI: 10.1042/BJ3360593

Abstract: The analysis of mutations associated with glycosylation-defective cell lines has the potential for identifying critical residues associated with the activities of enzymes involved in the biosynthesis of glycoconjugates. A ricin-resistant (RicR) baby hamster kidney (BHK) cell mutant, clone RicR14, has a deficiency in N-acetylglucosaminyltransferase I (GlcNAc-TI) activity and as a consequence is unable to synthesize complex and hybrid N-glycans. Here we show that RicR14 cells transfected with wild-type GlcNAc-TI regained the ability to synthesize complex N-glycans, demonstrating that the glycosylation defect of RicR14 cells is due solely to the lack of GlcNAc-TI activity. With the use of specific antibodies to GlcNAc-TI, RicR14 cells were shown to synthesize an inactive GlcNAc-TI protein that is correctly localized to the Golgi apparatus. We have cloned and sequenced the open reading frame of GlcNAc-TI from parental BHK and RicR14 cells. A comparison of several RicR14 cDNA clones with the parental BHK GlcNAc-TI sequence indicated the presence of two different RicR14 cDNA species. One contained a premature stop codon at position +81, whereas the second contained a point mutation in the catalytic domain of GlcNAc-TI resulting in the amino acid substitution Gly320 → Asp. The introduction of a Gly320 → Asp mutation into wild-type rabbit GlcNAc-TI resulted in a complete loss of activity the GlcNAc-TI mutant was correctly localized to the Golgi, indicating that the inactive GlcNAc-TI protein was transport-competent. Gly320 is conserved in GlcNAc-TI from all species so far examined. Overall these results demonstrate that Gly320 is a critical residue for GlcNAc-TI activity. The nucleotide sequence data reported will appear in DDBJ, EMBL and GenBank Nucleotide Sequence Databases under the accession numbers AF087456 and AF087457.

A systematic review of interventions on body image and disordered eating outcomes among women in midlife.

Publisher: Wiley

Date: 26-11-2016

DOI: 10.1002/EAT.22480

Abstract: Body dissatisfaction and disordered eating are widely recognized as issues that warrant attention among women in midlife, particularly the development and delivery of effective interventions. This article systematically reviews existing research on interventions among midlife women on body image and disordered eating outcomes, in order to inform intervention delivery and provide strategic directions for future research. Fourteen electronic databases were searched for articles published between 1992 and 2015 that evaluated interventions with nonclinical s les of women (M age 35-55 years) in controlled trials with at least one body image measure. Data were extracted and evaluated, and the methodological quality of studies was assessed using the Cochrane Collaboration tool for assessing risk of bias. From 7,475 records identified, nine articles evaluating 11 interventions met the inclusion criteria. Seven interventions significantly improved body image at post-test (d's = 0.19-2.22), with significant improvements on disordered eating achieved by two of these interventions (d's = 0.90-1.72). Sustained improvements were achieved by three interventions that employed a multisession, therapeutically based, group intervention format two with sustained body image and disordered eating improvements, and one with sustained body image improvements only (d's = 0.55-1.21 2 weeks to 6 months). Methodological quality varied between studies. To date, three interventions have demonstrated sustained improvements and are indicated for practitioners aiming to improve body image and disordered eating among women in midlife. Replication and more rigorous randomised controlled trials are required to enhance the methodological quality of intervention studies in this field.

Absence of pro-survival A1 has no impact on inflammatory cell survival in vivo during acute lung inflammation and peritonitis

Publisher: Springer Science and Business Media LLC

Date: 24-07-2022

DOI: 10.1038/S41418-021-00839-3

Circulating BiP/Grp78 is a novel prognostic marker for sepsis‐mediated immune cell death

Publisher: Wiley

Date: 17-09-2020

DOI: 10.1111/FEBS.15552

ROCK1 but not LIMK1 or PAK2 is a key regulator of apoptotic membrane blebbing and cell disassembly

Publisher: Springer Science and Business Media LLC

Date: 05-2019

DOI: 10.1038/S41418-019-0342-5

Influenza A virus infection‐induced macroautophagy facilitates MHC class II‐restricted endogenous presentation of an immunodominant viral epitope

Publisher: Wiley

Date: 18-12-2021

DOI: 10.1111/FEBS.15654

Control of apoptosis in hematopoietic cells by the Bcl-2 family of proteins.

Publisher: Cold Spring Harbor Laboratory

Date: 1999

DOI: 10.1101/SQB.1999.64.351

TREML4 receptor regulates inflammation and innate immune cell death during polymicrobial sepsis

Publisher: Springer Science and Business Media LLC

Date: 05-10-2020

DOI: 10.1038/S41590-020-0789-Z

Abstract: Sepsis is a biphasic disease characterized by an acute inflammatory response, followed by a prolonged immunosuppressive phase. Therapies aimed at controlling inflammation help to reduce the time patients with sepsis spend in intensive care units, but they do not lead to a reduction in overall mortality. Recently, the focus has been on addressing the immunosuppressive phase, often caused by apoptosis of immune cells. However, molecular triggers of these events are not yet known. Using whole-genome CRISPR screening in mice, we identified a triggering receptor expressed on myeloid cells (TREM) family receptor, TREML4, as a key regulator of inflammation and immune cell death in sepsis. Genetic ablation of Treml4 in mice demonstrated that TREML4 regulates calcium homeostasis, the inflammatory cytokine response, myeloperoxidase activation, the endoplasmic reticulum stress response and apoptotic cell death in innate immune cells, leading to an overall increase in survival rate, both during the acute and chronic phases of polymicrobial sepsis.

The proapoptotic activity of the Bcl-2 family member Bim is regulated by interaction with the dynein motor complex.

Publisher: Elsevier BV

Date: 03-1990

DOI: 10.1016/S1097-2765(00)80456-6

Abstract: Bcl-2 family members that have only a single Bcl-2 homology domain, BH3, are potent inducers of apoptosis, and some appear to play a critical role in developmentally programmed cell death. We examined the regulation of the proapoptotic activity of the BH3-only protein Bim. In healthy cells, most Bim molecules were bound to LC8 cytoplasmic dynein light chain and thereby sequestered to the microtubule-associated dynein motor complex. Certain apoptotic stimuli disrupted the interaction between LC8 and the dynein motor complex. This freed Bim to translocate together with LC8 to Bcl-2 and to neutralize its antiapoptotic activity. This process did not require caspase activity and therefore constitutes an initiating event in apoptosis signaling.

Glycosylation defect in Lec1 Chinese hamster ovary mutant is due to a point mutation in N-acetylglucosaminyltransferase I gene.

Publisher: Elsevier BV

Date: 11-1996

DOI: 10.1074/JBC.271.44.27818

BCL-2 family protein BOK is a positive regulator of uridine metabolism in mammals

Publisher: Proceedings of the National Academy of Sciences

Date: 16-07-2019

DOI: 10.1073/PNAS.1904523116

Abstract: It is believed that the Bcl-2 family protein Bok has a redundant role similar to Bax and Bak in regulating apoptosis. We report that this protein interacts with the key enzyme involved in uridine biosynthesis, uridine monophosphate synthetase, and positively regulates uridine biosynthesis and chemoconversion of 5-fluorouracil (5-FU). Bok-deficient cell lines are resistant to 5-FU. Bok down-regulation is a key feature of cell lines and primary colorectal tumor tissues that are resistant to 5-FU. Our data also show that through its impact on nucleotide metabolism, Bok regulates p53 level and cellular proliferation. Our results have implications for developing Bok as a biomarker for 5-FU resistance and for the development of BOK mimetics for sensitizing 5-FU-resistant cancers.

La Trobe University

Location: Australia

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Monash University

Location: Australia

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Walter And Eliza Hall Institute Of Medical Research

Location: Australia

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Maharaja Sayajirao University Of Baroda Department Of Microbiology And Biotechnology Centre

Location: India

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Discovery Projects - Grant ID: DP110100417

Start Date: 2011

End Date: 12-2014

Amount: $300,000.00

Funder: Australian Research Council

ARC Future Fellowships - Grant ID: FT0990683

Start Date: 03-2010

End Date: 12-2014

Amount: $788,800.00

Funder: Australian Research Council

Understanding The Biological Basis Of Cancer Cachexia

Start Date: 2016

End Date: 2019

Funder: Victorian Cancer Agency

Cancer Cachexia Therapeutics

Start Date: 2016

End Date: 2018

Funder: National Health and Medical Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE130100114

Start Date: 2013

End Date: 12-2014

Amount: $420,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE120100090

Start Date: 01-2012

End Date: 12-2013

Amount: $640,000.00

Funder: Australian Research Council

Multi-scale Imaging And Characterisation Facility For Biological Structure And Function

Start Date: 2013

End Date: 2013

Funder: Australian Research Council