ORCID Profile
0000-0002-8041-9666
Current Organisation
University of South Australia
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Publisher: Springer Science and Business Media LLC
Date: 23-06-2016
DOI: 10.1007/S10456-016-9520-Y
Abstract: Desmogleins (DSG) are a family of cadherin adhesion proteins that were first identified in desmosomes and provide cardiomyocytes and epithelial cells with the junctional stability to tolerate mechanical stress. However, one member of this family, DSG2, is emerging as a protein with additional biological functions on a broader range of cells. Here we reveal that DSG2 is expressed by non-desmosome-forming human endothelial progenitor cells as well as their mature counterparts [endothelial cells (ECs)] in human tissue from healthy in iduals and cancer patients. Analysis of normal blood and bone marrow showed that DSG2 is also expressed by CD34(+)CD45(dim) hematopoietic progenitor cells. An inability to detect other desmosomal components, i.e., DSG1, DSG3 and desmocollin (DSC)2/3, on these cells supports a solitary role for DSG2 outside of desmosomes. Functionally, we show that CD34(+)CD45(dim)DSG2(+) progenitor cells are multi-potent and pro-angiogenic in vitro. Using a 'knockout-first' approach, we generated a Dsg2 loss-of-function strain of mice (Dsg2 (lo/lo)) and observed that, in response to reduced levels of Dsg2: (i) CD31(+) ECs in the pancreas are hypertrophic and exhibit altered morphology, (ii) bone marrow-derived endothelial colony formation is impaired, (iii) ex vivo vascular sprouting from aortic rings is reduced, and (iv) vessel formation in vitro and in vivo is attenuated. Finally, knockdown of DSG2 in a human bone marrow EC line reveals a reduction in an in vitro angiogenesis assay as well as relocalisation of actin and VE-cadherin away from the cell junctions, reduced cell-cell adhesion and increased invasive properties by these cells. In summary, we have identified DSG2 expression in distinct progenitor cell subpopulations and show that, independent from its classical function as a component of desmosomes, this cadherin also plays a critical role in the vasculature.
Publisher: Wiley
Date: 2020
DOI: 10.1002/CTI2.1191
Publisher: Public Library of Science (PLoS)
Date: 26-10-2012
Publisher: Wiley
Date: 2019
DOI: 10.1002/CTI2.1050
Publisher: American Association for Cancer Research (AACR)
Date: 04-2009
DOI: 10.1158/1078-0432.CCR-08-2424
Abstract: Purpose: Ipilimumab is a monoclonal antibody that blocks the immune-inhibitory interaction between CTL antigen 4 (CTLA-4) and its ligands on T cells. Clinical trials in cancer patients with ipilimumab have shown promising antitumor activity, particularly in patients with advanced melanoma. Often, tumor regressions in these patients are correlated with immune-related side effects such as dermatitis, enterocolitis, and hypophysitis. Although these reactions are believed to be immune-mediated, the antigenic targets for the cellular or humoral immune response are not known. Experimental Design: We enrolled patients with advanced melanoma in a phase II study with ipilimumab. One of these patients experienced a complete remission of his tumor. The specificity and functional properties of CD8-positive T cells in his peripheral blood, in regressing tumor tissue, and at the site of an immune-mediated skin rash were investigated. Results: Regressing tumor tissue was infiltrated with CD8-positive T cells, a high proportion of which were specific for Melan-A. The skin rash was similarly infiltrated with Melan-A–specific CD8-positive T cells, and a dramatic (& -fold) increase in Melan-A–specific CD8-positive T cells was apparent in peripheral blood. These cells had an effector phenotype and lysed Melan-A–expressing tumor cells. Conclusions: Our results show that Melan-A may be a major target for both the autoimmune and antitumor reactions in patients treated with anti-CTLA-4, and describe for the first time the antigen specificity of CD8-positive T cells that mediate tumor rejection in a patient undergoing treatment with an anti-CTLA-4 antibody. These findings may allow a better integration of ipilimumab into other forms of immunotherapy.
Publisher: Elsevier BV
Date: 05-2005
DOI: 10.1016/J.MOLIMM.2004.06.040
Abstract: Antigen-driven T cell education and subsequent pathogen elimination present particular challenges for the immune system. Pathogens generally enter the body at peripheral sites such as the skin, gastrointestinal tract or lung, areas from which naïve T cells are largely excluded. Instead, naïve T cells constantly recirculate through secondary lymphoid organs, such as lymph nodes and Peyer's patches, in search for antigen brought to these locations by means of afferent lymphatic channels. Here, antigen-loaded dendritic cells present antigen-peptide-MHC complexes to clonotypic T cells and provide appropriate co-stimulatory signals for immune response initiation. As a result, short-lived effector T cells and long-lived memory T cells are generated that reach the peripheral tissue for participation in immune responses and immune surveillance. Effector and memory T cell relocation is non-random, due to tissue-specific "address codes" that allow proper tissue homing. This process involves adhesion molecules, including selectins, integrins, and corresponding vascular ligands as well as the large family of chemokines and their receptors. Here, we discuss the changes in chemokine receptor expression that occur during T cell activation and differentiation, and the ways in which these changes impact on the migration potential of naïve, effector, and memory T cells. We summarize our current understanding of T cell homing to the T zone and B cell follicles within secondary lymphoid tissues and highlight the two chemokine receptors CCR7 and CXCR5 that recognize chemokines constitutively present either in the T zone (CCR7 ligands CCL19/ELC and CCL21/SLC) or follicular compartment (CXCR5 ligand CXCL13/BCA-1). CCR7 is characteristic for naive and central memory T (T(CM)) cells whereas CXCR5 distinguishes follicular B helper T (T(FH)) cells. In addition, we further sub ide long-lived memory T cells into CCR7-negative effector memory T (T(EM)) cells and peripheral immune surveillance T (T(PS)) cells. The latter term designates the extraordinarily large subset of memory T cells with primary residence in normal (healthy) peripheral tissues. Our current understanding of T(PS) cell migration and function is highly fragmentary, but these cells are thought to provide immediate protection locally at the site of pathogen entry. Here, we propose that the tissue distribution of T(PS) cells is determined by a distinct set of chemokines and corresponding receptors that differs from those operating in secondary lymphoid tissues and inflammatory sites.
Publisher: Informa UK Limited
Date: 06-2010
DOI: 10.1586/ERV.10.58
Abstract: The rigorous evaluation of cancer vaccination requires evidence of benefit to patients with cancer or those at risk of relapse from the disease. Clinical trials are expensive and require considerable human and clinical resources in order to demonstrate this benefit. In the era of defined cancer antigens, it is possible to evaluate immunogenic targets, and assess the quality and magnitude of immune responses against these antigens following vaccination. Analyzing these surrogate end points complements clinical assessment and provides a depth of understanding to better inform trial evaluation and design. We have used the immunogenic cancer testis antigen NY-ESO-1 as a model antigen. This article summarizes our experience in monitoring immunity against NY-ESO-1.
Publisher: Frontiers Media SA
Date: 06-04-2022
DOI: 10.3389/FIMMU.2022.850226
Abstract: Glioblastoma is the most common and aggressive form of primary brain cancer, with no improvements in the 5-year survival rate of 4.6% over the past three decades. T-cell-based immunotherapies such as immune-checkpoint inhibitors and chimeric antigen receptor T-cell therapy have prolonged the survival of patients with other cancers and have undergone early-phase clinical evaluation in glioblastoma patients. However, a major challenge for T-cell-based immunotherapy of glioblastoma and other solid cancers is T-cell infiltration into tumours. This process is mediated by chemokine-chemokine receptor and integrin-adhesion molecule interactions, yet the specific nature of the molecules that may facilitate T-cell homing into glioblastoma are unknown. Here, we have characterised chemokine receptor and integrin expression profiles of endogenous glioblastoma-infiltrating T cells, and the chemokine expression profile of glioblastoma-associated cells, by single-cell RNA-sequencing. Subsequently, chemokine receptors and integrins were validated at the protein level to reveal enrichment of receptors CCR2, CCR5, CXCR3, CXCR4, CXCR6, CD49a, and CD49d in glioblastoma-infiltrating T-cell populations relative to T cells in matched patient peripheral blood. Complementary chemokine ligand expression was then validated in glioblastoma biopsies and glioblastoma-derived primary cell cultures. Together, enriched expression of homing receptor-ligand pairs identified in this study implicate a potential role in mediating T-cell infiltration into glioblastoma. Importantly, our data characterising the migratory receptors on endogenous tumour-infiltrating T cells could be exploited to enhance the tumour-homing properties of future T-cell immunotherapies for glioblastoma.
Publisher: Springer Science and Business Media LLC
Date: 02-03-2020
DOI: 10.1007/S11517-020-02147-3
Abstract: Histopathological whole slide images of haematoxylin and eosin (H& E)-stained biopsies contain valuable information with relation to cancer disease and its clinical outcomes. Still, there are no highly accurate automated methods to correlate histolopathological images with brain cancer patients’ survival, which can help in scheduling patients therapeutic treatment and allocate time for preclinical studies to guide personalized treatments. We now propose a new classifier, namely, DeepSurvNet powered by deep convolutional neural networks, to accurately classify in 4 classes brain cancer patients’ survival rate based on histopathological images (class I, 0–6 months class II, 6–12 months class III, 12–24 months and class IV, months survival after diagnosis). After training and testing of DeepSurvNet model on a public brain cancer dataset, The Cancer Genome Atlas, we have generalized it using independent testing on unseen s les. Using DeepSurvNet, we obtained precisions of 0.99 and 0.8 in the testing phases on the mentioned datasets, respectively, which shows DeepSurvNet is a reliable classifier for brain cancer patients’ survival rate classification based on histopathological images. Finally, analysis of the frequency of mutations revealed differences in terms of frequency and type of genes associated to each class, supporting the idea of a different genetic fingerprint associated to patient survival. We conclude that DeepSurvNet constitutes a new artificial intelligence tool to assess the survival rate in brain cancer.
Publisher: American Association for Cancer Research (AACR)
Date: 15-04-2008
DOI: 10.1158/0008-5472.CAN-07-5664
Abstract: FoxP3 is a member of the forkhead family of transcription factors critically involved in the development and function of CD25+ regulatory T cells (Treg). Until recently, FoxP3 expression was thought to be restricted to the T-cell lineage. However, using immunohistochemistry and flow cytometric analysis of human melanoma tissue, we detected FoxP3 expression not only in the tumor infiltrating Treg but also in the melanoma cells themselves. FoxP3 is also widely expressed by established human melanoma cell lines (as determined by flow cytometry, PCR, and Western blot), as well as cell lines derived from other solid tumors. Normal B cells do not express FoxP3 however, expression could be induced after transformation with EBV in vitro and in vivo, suggesting that malignant transformation of healthy cells can induce FoxP3. In addition, a FOXP3 mRNA variant lacking exons 3 and 4 was identified in tumor cell lines but was absent from Treg. Interestingly, this alternative splicing event introduces a translation frame-shift that is predicted to encode a novel protein. Together, our results show that FoxP3, a key regulator of immune suppression, is not only expressed by Treg but also by melanoma cells, EBV-transformed B cells, and a wide variety of tumor cell lines. [Cancer Res 2008 (8):3001–9]
Publisher: Springer Science and Business Media LLC
Date: 02-07-2021
DOI: 10.1186/S12885-021-08482-4
Abstract: The formation of blood vessels within solid tumors directly contributes to cancer growth and metastasis. Until recently, tumor vasculature was thought to occur exclusively via endothelial cell (EC) lined structures (i.e. angiogenesis), but a second source of tumor vasculature arises from the cancer cells themselves, a process known as vasculogenic mimicry (VM). While it is generally understood that the function of VM vessels is the same as that of EC-lined vessels (i.e. to supply oxygen and nutrients to the proliferating cancer cells), the molecular mechanisms underpinning VM are yet to be fully elucidated. Human VM-competent melanoma cell lines were examined for their VM potential using the in vitro angiogenesis assays (Matrigel), together with inhibition studies using small interfering RNA and blocking monoclonal antibodies. Invasion assays and adhesion assays were used to examine cancer cell function. Herein we demonstrate that CD36, a cell surface glycoprotein known to promote angiogenesis by ECs, also supports VM formation by human melanoma cancer cells. In silico analysis of CD36 expression within the melanoma cohort of The Cancer Genome Atlas suggests that melanoma patients with high expression of CD36 have a poorer clinical outcome. Using in vitro ‘angiogenesis’ assays and CD36-knockdown approaches, we reveal that CD36 supports VM formation by human melanoma cells as well as adhesion to, and invasion through, a cancer derived extracellular matrix substrate. Interestingly, thrombospondin-1 (TSP-1), a ligand for CD36 on ECs that inhibits angiogenesis, has no effect on VM formation. Further investigation revealed a role for laminin, but not collagen or fibronectin, as ligands for CD36 expressing melanoma cells. Taken together, this study suggests that CD36 is a novel regulator of VM by melanoma cancer cells that is facilitated, at least in part, via integrin-α 3 and laminin. Unlike angiogenesis, VM is not perturbed by the presence of TSP-1, thus providing new information on differences between these two processes of tumor vascularization which may be exploited to combat cancer progression.
Publisher: Elsevier BV
Date: 2003
DOI: 10.1016/S0165-2478(02)00233-X
Abstract: Follicular B helper T (T(FH)) cells make up a CD4(+) memory T cell subset with unique migration properties, defined by the expression of the chemokine receptor CXCR5 and responsiveness to the CXCR5-selective chemokine BCA-1, which is produced in B cell follicles. The generation of T(FH) cells is closely associated with initiation of adaptive immunity. Here, we discuss the relationship of T(FH) cells with those T cells characterized by an inherent secondary lymphoid tissue homing program. Special emphasis is placed on the potential involvement of T(FH) cells in the humoral immune response within B cell follicles, as well as the differentiation potential of these non-polarized cells.
Publisher: Portland Press Ltd.
Date: 14-03-2018
DOI: 10.1042/BST20170178
Abstract: Chimeric antigen receptor (CAR)-T cell therapy has been clinically validated as a curative treatment for the difficult to treat malignancies of relapsed/refractory B-cell acute lymphoblastic leukaemia and lymphoma. Here, the CAR-T cells are re-directed towards a single antigen, CD19, which is recognised as a virtually ideal CAR target antigen because it has strong, uniform expression on cancer cells, and is otherwise expressed only on healthy B cells, which are ‘dispensable’. Notwithstanding the clinical success of CD19-CAR-T cell therapy, its single specificity has driven therapeutic resistance in 30% or more of cases with CD19-negative leukaemic relapses. Immune checkpoint blockade is also a highly successful cancer immunotherapeutic approach, but it will be less useful for many patients whose malignancies either lack a substantial somatic mutation load or whose tumours are intrinsically resistant. Although CAR-T cell therapy could serve this unmet medical need, it is beset by several major limitations. There is a lack of candidate antigens that would satisfy the requirements for ideal CAR targets. Biological properties such as clonal heterogeneity and micro-environmental conditions hostile to T cells are inherent to many solid tumours. Past clinical studies indicate that on-target, off-tumour toxicities of CAR-T cell therapy may severely h er its application. Therefore, re-designing CARs to increase the number of antigen specificities recognised by CAR-T cells will broaden tumour antigen coverage, potentially overcoming tumour heterogeneity and limiting tumour antigen escape. Tuning the balance of signalling within bi-specific CAR-T cells may enable tumour targeting while sparing normal tissues, and thus minimise on-target, off-tumour toxicities.
Publisher: Frontiers Media SA
Date: 20-10-2023
Publisher: Wiley
Date: 06-2006
DOI: 10.1111/J.1440-1711.2006.01446.X
Abstract: Since the early 1990s, numerous cancer Ag have been defined and for a handful of these there is now some clinical experience, which has made it possible to assess their value as targets for cancer immunotherapy. The cancer-testis Ag have been particularly attractive because their expression is limited to cancer and virtually no non-malignant cells apart from germ cells and trophoblast. Among these, NY-ESO-1 has been the focus of our attention. The exceptional immunogenicity of this Ag coupled with its widespread distribution among many cancer types make it a very good vaccine candidate, with the potential to be used in vaccines against many types of malignancies. This article reviews emerging knowledge about the biology of NY-ESO-1 and experience with the early clinical development of vaccines directed against NY-ESO-1. These early studies have yielded a wealth of information about the immunology of NY-ESO-1 and set the scene for future clinical strategies for immune targeting of cancer.
Publisher: American Association for Cancer Research (AACR)
Date: 15-03-2009
DOI: 10.1158/1078-0432.CCR-08-2484
Abstract: Purpose: NY-ESO-1 is a highly immunogenic antigen expressed in a variety of malignancies, making it an excellent target for cancer vaccination. We recently developed a vaccine consisting of full-length recombinant NY-ESO-1 protein formulated with ISCOMATRIX adjuvant, which generated strong humoral and T-cell–mediated immune responses and seemed to reduce the risk of disease relapse in patients with fully resected melanoma. This study examines the clinical and immunologic efficacy of the same vaccine in patients with advanced metastatic melanoma. Experimental Design: Delayed-type hypersensitivity responses, circulating NY-ESO-1–specific CD4+ and CD8+ T cells, and proportions of regulatory T cells (Treg) were assessed in patients. Results: In contrast to patients with minimal residual disease, advanced melanoma patients showed no clinical responses to vaccination. Although strong antibody responses were mounted, the generation of delayed-type hypersensitivity responses was significantly impaired. The proportion of patients with circulating NY-ESO-1–specific CD4+ T cells was also reduced, and although many patients had CD8+ T cells specific to a broad range of NY-ESO-1 epitopes, the majority of these responses were preexisting. Tregs were enumerated in the blood by flow cytometric detection of cells with a CD4+CD25+FoxP3+ and CD4+CD25+CD127− phenotype. Patients with advanced melanoma had a significantly higher proportion of circulating Treg compared with those with minimal residual disease. Conclusions: Our results point to a tumor-induced systemic immune suppression, showing a clear association between the stage of melanoma progression, the number of Treg in the blood, and the clinical and immunologic efficacy of the NY-ESO-1 ISCOMATRIX cancer vaccine.
Publisher: Wiley
Date: 25-02-2023
Abstract: Accurate delineation of gross tumor volumes remains a barrier to radiotherapy dose escalation and boost dosing in the treatment of solid tumors, such as prostate cancer. Magnetic resonance imaging (MRI) of tumor targets has the power to enable focal dose boosting, particularly when combined with technological advances such as MRI‐linear accelerator. Fibroblast activation protein (FAP) is overexpressed in stromal components of % of epithelial carcinomas. Herein, the authors compare targeted MRI of prostate specific membrane antigen (PSMA) with FAP in the delineation of orthotopic prostate tumors. Control, FAP, and PSMA‐targeting iron oxide nanoparticles were prepared with modification of a lymphotropic MRI agent (FerroTrace, Ferronova). Mice with orthotopic LNCaP tumors underwent MRI 24 h after intravenous injection of nanoparticles. FAP and PSMA nanoparticles produced contrast enhancement on MRI when compared to control nanoparticles. FAP‐targeted MRI increased the proportion of tumor contrast‐enhancing black pixels by 13%, compared to PSMA. Analysis of changes in R2 values between healthy prostates and LNCaP tumors indicated an increase in contrast‐enhancing pixels in the tumor border of 15% when targeting FAP, compared to PSMA. This study demonstrates the preclinical feasibility of PSMA and FAP‐targeted MRI which can enable targeted image‐guided focal therapy of localized prostate cancer.
Publisher: Elsevier BV
Date: 05-2015
DOI: 10.1016/J.SCR.2015.04.002
Abstract: Circulating endothelial progenitor cells (EPCs) provide revascularisation for cardiovascular disease and the expansion of these cells opens up the possibility of their use as a cell therapy. Herein we show that interleukin-3 (IL3) strongly expands a population of human non-adherent endothelial forming cells (EXnaEFCs) with low immunogenicity as well as pro-angiogenic capabilities in vivo, making their therapeutic utilisation a realistic option. Non-adherent CD133(+) EFCs isolated from human umbilical cord blood and cultured under different conditions were maximally expanded by day 12 in the presence of IL3 at which time a 350-fold increase in cell number was obtained. Cell surface marker phenotyping confirmed expression of the hematopoietic progenitor cell markers CD133, CD117 and CD34, vascular cell markers VEGFR2 and CD31, dim expression of CD45 and absence of myeloid markers CD14 and CD11b. Functional experiments revealed that EXnaEFCs exhibited classical properties of endothelial cells (ECs), namely binding of Ulex europaeus lectin, up-take of acetylated-low density lipoprotein and contribution to EC tube formation in vitro. These EXnaEFCs demonstrated a pro-angiogenic phenotype within two independent in vivo rodent models. Firstly, a Matrigel plug assay showed increased vascularisation in mice. Secondly, a rat model of acute myocardial infarction demonstrated reduced heart damage as determined by lower levels of serum creatinine and a modest increase in heart functionality. Taken together, these studies show IL3 as a potent growth factor for human CD133(+) cell expansion with clear pro-angiogenic properties (in vitro and in vivo) and thus may provide clinical utility for humans in the future.
Publisher: Elsevier BV
Date: 09-2005
DOI: 10.1016/J.IMMUNI.2005.08.012
Abstract: Dendritic cells (DCs) are major constituents of peripheral tissues, where they control immunity to foreign and self-antigens. The process of continuous DC renewal under homeostatic conditions is largely undefined. Here, we demonstrate that CD14+ DC precursors, either derived from CD34+ hematopoietic progenitor cells or isolated from blood, were attracted by the chemokine CXCL14, which is constitutively produced in healthy skin and other epithelial tissues. In a tissue model we show that human epidermal equivalents profoundly affected CD14+ DC precursors, including their suprabasal positioning and survival as well as their differentiation into Langerhans cell-like cells with potent antigen-presentation functions. Our model assigns unprecedented roles to CXCL14 and epidermal tissue as attractant and niche of differentiation, respectively, in the renewal of Langerhans cells under steady-state conditions.
Publisher: Wiley
Date: 11-09-2023
DOI: 10.1111/IMCB.12690
Publisher: Wiley
Date: 24-07-2021
Abstract: Multiple myeloma (MM) is the second most common haematological malignancy and is an incurable disease of neoplastic plasma cells (PC). Newly diagnosed MM patients currently undergo lengthy genetic testing to match chromosomal mutations with the most potent drug/s to decelerate disease progression. With only 17% of MM patients surviving 10‐years postdiagnosis, faster detection and earlier intervention would unequivocally improve outcomes. Here, we show that the cell surface protein desmoglein‐2 (DSG2) is overexpressed in ~ 20% of bone marrow biopsies from newly diagnosed MM patients. Importantly, DSG2 expression was strongly predictive of poor clinical outcome, with patients expressing DSG2 above the 70 th percentile exhibiting an almost 3‐fold increased risk of death. As a prognostic factor, DSG2 is independent of genetic subtype as well as the routinely measured biomarkers of MM activity (e.g. paraprotein). Functional studies revealed a nonredundant role for DSG2 in adhesion of MM PC to endothelial cells. Together, our studies suggest DSG2 to be a potential cell surface biomarker that can be readily detected by flow cytometry to rapidly predict disease trajectory at the time of diagnosis.
Publisher: BMJ
Date: 09-2022
Abstract: Aggressive primary brain tumors such as glioblastoma are uniquely challenging to treat. The intracranial location poses barriers to therapy, and the potential for severe toxicity. Effective treatments for primary brain tumors are limited, and 5-year survival rates remain poor. Immune checkpoint inhibitor therapy has transformed treatment of some other cancers but has yet to significantly benefit patients with glioblastoma. Early phase trials of chimeric antigen receptor (CAR) T-cell therapy in patients with glioblastoma have demonstrated that this approach is safe and feasible, but with limited evidence of its effectiveness. The choices of appropriate target antigens for CAR-T-cell therapy also remain limited. We profiled an extensive biobank of patients’ biopsy tissues and patient-derived early passage glioma neural stem cell lines for GD2 expression using immunomicroscopy and flow cytometry. We then employed an approved clinical manufacturing process to make CAR- T cells from patients with peripheral blood of glioblastoma and diffuse midline glioma and characterized their phenotype and function in vitro. Finally, we tested intravenously administered CAR-T cells in an aggressive intracranial xenograft model of glioblastoma and used multicolor flow cytometry, multicolor whole-tissue immunofluorescence and next-generation RNA sequencing to uncover markers associated with effective tumor control. Here we show that the tumor-associated antigen GD2 is highly and consistently expressed in primary glioblastoma tissue removed at surgery. Moreover, despite patients with glioblastoma having perturbations in their immune system, highly functional GD2-specific CAR-T cells can be produced from their peripheral T cells using an approved clinical manufacturing process. Finally, after intravenous administration, GD2-CAR-T cells effectively infiltrated the brain and controlled tumor growth in an aggressive orthotopic xenograft model of glioblastoma. Tumor control was further improved using CAR-T cells manufactured with a clinical retroviral vector encoding an interleukin-15 transgene alongside the GD2-specific CAR. These CAR-T cells achieved a striking 50% complete response rate by bioluminescence imaging in established intracranial tumors. Targeting GD2 using a clinically deployed CAR-T-cell therapy has a sound scientific and clinical rationale as a treatment for glioblastoma and other aggressive primary brain tumors.
Publisher: Wiley
Date: 12-2004
Abstract: The CXC chemokine receptor (CXCR)5 is rapidly induced on activated CD4(+) T cells, allowing migration toward secondary lymphoid tissue follicles, where the CXCR5 ligand CXCL13/BCA-1 is produced. Such CXCR5(+) T cells provide efficient help for B cell immunoglobulin production and are termed follicular B helper T (T(FH)) cells. However, the molecular mechanisms by which T(FH) cells provide B cell help are unknown. Here, we demonstrate that newly generated (antigen-primed) T(FH) cells express a phenotype consistent with induction of B cell proliferation, but co-culture with primed B cells resulted in a switch to a plasma cell-inducing phenotype, characterized by loss of CD154, induction of CD70 and an increase in IL-10 production capacity. The ability to produce IL-10 could be maintained as a stable phenotype, but its secretion was strictly dependent on inducible costimulator (ICOS) signaling. Furthermore, B cells preserved a lymph node migration phenotype in proliferating T(FH) cells by preventing the loss of CC chemokine receptor (CCR)7 and the induction of CCR5. Thus, B cells directly modulate the B cell helper phenotype in T(FH) cells and actively promote their prolonged co-localization with these cells.
Publisher: Frontiers Media SA
Date: 14-06-2023
DOI: 10.3389/FIMMU.2023.1187332
Abstract: The clinical success of immune-checkpoint inhibitors (ICI) in both resected and metastatic melanoma has confirmed the validity of therapeutic strategies that boost the immune system to counteract cancer. However, half of patients with metastatic disease treated with even the most aggressive regimen do not derive durable clinical benefit. Thus, there is a critical need for predictive biomarkers that can identify in iduals who are unlikely to benefit with high accuracy so that these patients may be spared the toxicity of treatment without the likely benefit of response. Ideally, such an assay would have a fast turnaround time and minimal invasiveness. Here, we utilize a novel platform that combines mass spectrometry with an artificial intelligence-based data processing engine to interrogate the blood glycoproteome in melanoma patients before receiving ICI therapy. We identify 143 biomarkers that demonstrate a difference in expression between the patients who died within six months of starting ICI treatment and those who remained progression-free for three years. We then develop a glycoproteomic classifier that predicts benefit of immunotherapy (HR=2.7 p=0.026) and achieves a significant separation of patients in an independent cohort (HR=5.6 p=0.027). To understand how circulating glycoproteins may affect efficacy of treatment, we analyze the differences in glycosylation structure and discover a fucosylation signature in patients with shorter overall survival (OS). We then develop a fucosylation-based model that effectively stratifies patients (HR=3.5 p=0.0066). Together, our data demonstrate the utility of plasma glycoproteomics for biomarker discovery and prediction of ICI benefit in patients with metastatic melanoma and suggest that protein fucosylation may be a determinant of anti-tumor immunity.
Publisher: Elsevier BV
Date: 06-2019
DOI: 10.1016/J.JCYT.2019.03.003
Abstract: Chimeric antigen receptor (CAR)-T cells are genetically engineered to recognize tumor-associated antigens and have potent cytolytic activity against tumors. Adoptive therapy with CAR-T cells has been highly successful in B-cell leukemia and lymphoma. However, in solid tumor settings, CAR-T cells face a particularly hostile tumor microenvironment where multiple immune suppressive factors serve to thwart the anti-cancer immune response. Clinical trials of solid tumor antigen-targeted CAR-T cells have shown limited efficacy, and issues for current CAR-T cell therapies include failures of expansion and persistence, tumor entry, deletion and functional exhaustion. We compared our standard protocol for CAR-T cell manufacturing, currently used to generate CAR-T cells for a phase 1 clinical trial, with two alternative approaches for T-cell activation and expansion. The resulting cultures were analyzed using multicolor flow cytometry, cytokine bead array and xCELLigence cytotoxicity assays. We have found that by changing the method of activation we can promote generation of CAR-T cells with enhanced CD62L and CCR7 expression, increased interleukin (IL)-2 production and retention of cytolytic activity, albeit with slower kinetics. We propose that these phenotypic characteristics are consistent with a central memory phenotype that will better enable CAR-T cell survival and persistence after activation in vivo, and we aim to test this in a continuation of our current phase 1 clinical trial of CAR-T cells in patients with advanced melanoma.
Publisher: American Association for Cancer Research (AACR)
Date: 29-01-2009
DOI: 10.1158/0008-5472.CAN-08-2926
Abstract: The tumor antigen NY-ESO-1 is a promising cancer vaccine target. We describe here a novel HLA-B7–restricted NY-ESO-1 epitope, encompassing amino acids 60-72 (APRGPHGGAASGL), which is naturally presented by melanoma cells. The tumor epitope bound to HLA-B7 by bulging outward from the peptide-binding cleft. This bulged epitope was not an impediment to T-cell recognition, however, because four of six HLA-B7+ melanoma patients vaccinated with NY-ESO-1 ISCOMATRIX vaccine generated a potent T-cell response to this determinant. Moreover, the response to this epitope was immunodominant in three of these patients and, unlike the T-cell responses to bulged HLA class I viral epitopes, the responding T cells possessed a remarkably broad TCR repertoire. Interestingly, HLA-B7+ melanoma patients who did not receive the NY-ESO-1 ISCOMATRIX vaccine rarely generated a spontaneous T-cell response to this cryptic epitope, suggesting a lack of priming of such T cells in the natural anti–NY-ESO-1 response, which may be corrected by vaccination. Together, our results reveal several surprising aspects of antitumor immunity and have implications for cancer vaccine design. [Cancer Res 2009 (3):1046–54]
Publisher: Wiley
Date: 05-12-2013
Abstract: CD4(+) CD25(+) FoxP3(+) naturally occurring regulatory T (Treg) cells play a crucial role in the maintenance of immune tolerance and in preventing autoimmune pathology. Interventions that expand Treg cells are highly desirable, as they may offer novel treatment options in a variety of autoimmune and transplantation settings. Paralleling previous preclinical studies, we demonstrate here that administration of the hematopoietic growth factor Flt3L to human subjects increases the frequency and absolute number of Treg cells, and reduces the ratio of CD8(+) T cells to Treg cells in the peripheral blood. The increase in Treg cells was due to enhanced Treg-cell proliferation rather than release of Treg cells from the thymus. Further studies revealed that Flt3L-induced proliferation of Treg cells was an indirect effect that occurred via the interaction of Treg cells with the Flt3L-expanded pool of CD1c(+) myeloid dendritic cells. On the basis of these findings, Flt3L may represent a promising agent for promoting immune tolerance in a variety of clinical settings.
Publisher: Elsevier BV
Date: 03-2012
DOI: 10.1016/J.JIM.2012.01.004
Abstract: Antigenic epitopes recognized by FoxP3(+) regulatory T cells (Treg) are poorly defined, largely due to a lack of assays for determining Treg specificity. We have developed a novel approach for detecting human Treg specific to peptide antigen, utilizing down-regulation of surface CD3 as a read-out of antigen recognition. Culture conditions and re-stimulation time have been optimized, allowing the detection of even very rare Treg, such as those specific to tumor antigens.
Publisher: Impact Journals, LLC
Date: 22-06-2016
Publisher: Informa UK Limited
Date: 09-03-2022
Publisher: MDPI AG
Date: 09-03-2021
Abstract: Glioblastoma is the most common form of primary brain tumour in adults. For more than a decade, conventional treatment has produced a relatively modest improvement in the overall survival of glioblastoma patients. The immunosuppressive mechanisms employed by neoplastic and non-neoplastic cells within the tumour can limit treatment efficacy, and this can include the secretion of immunosuppressive cytokines and chemokines. These factors can play a significant role in immune modulation, thus disabling anti-tumour responses and contributing to tumour progression. Here, we review the complex interplay between populations of immune and tumour cells together with defined contributions by key cytokines and chemokines to these intercellular interactions. Understanding how these tumour-derived factors facilitate the crosstalk between cells may identify molecular candidates for potential immunotherapeutic targeting, which may enable better tumour control and improved patient survival.
Publisher: Wiley
Date: 03-2017
DOI: 10.1038/CTI.2017.7
Publisher: MDPI AG
Date: 06-05-2021
Abstract: Adoptive T-cell therapy using autologous T cells genetically modified to express cancer-specific chimeric antigen receptors (CAR) has emerged as a novel approach for cancer treatment. CAR-T cell therapy has been approved in several major jurisdictions for treating refractory or relapsed cases of B-cell precursor acute lymphoblastic leukaemia and diffuse large B-cell lymphoma. However, in solid cancer patients, several clinical studies of CAR-T cell therapy have demonstrated minimal therapeutic effects, thus encouraging interest in better integrating CAR-T cells with other treatments such as conventional cytotoxic chemotherapy. Increasing evidence shows that not only do chemotherapy drugs have tumoricidal effects, but also significantly modulate the immune system. Here, we discuss immunomodulatory effects of chemotherapy drugs on circulating leukocyte populations, including their ability to enhance cytotoxic effects and preserve the frequency of CD8+ T cells and to deplete immunosuppressive populations including regulatory T cells and myeloid-derived suppressor cells. By modulating the abundance and phenotype of leukocytes in the blood (the ‘raw material’ for CAR-T cell manufacturing), we propose that prior chemotherapy could facilitate production of the most effective CAR-T cell products. Further research is required to directly test this concept and identify strategies for the optimal integration of CAR-T cell therapies with cytotoxic chemotherapy for solid cancers.
Publisher: MDPI AG
Date: 21-04-2021
DOI: 10.3390/IJMS22094322
Abstract: Glioblastoma is one of the most common and lethal types of primary brain tumor. Despite aggressive treatment with chemotherapy and radiotherapy, tumor recurrence within 6–9 months is common. To overcome this, more effective therapies targeting cancer cell stemness, invasion, metabolism, cell death resistance and the interactions of tumor cells with their surrounding microenvironment are required. In this study, we performed a systematic review of the molecular mechanisms that drive glioblastoma progression, which led to the identification of 65 drugs/inhibitors that we screened for their efficacy to kill patient-derived glioma stem cells in two dimensional (2D) cultures and patient-derived three dimensional (3D) glioblastoma explant organoids (GBOs). From the screening, we found a group of drugs that presented different selectivity on different patient-derived in vitro models. Moreover, we found that Costunolide, a TERT inhibitor, was effective in reducing the cell viability in vitro of both primary tumor models as well as tumor models pre-treated with chemotherapy and radiotherapy. These results present a novel workflow for screening a relatively large groups of drugs, whose results could lead to the identification of more personalized and effective treatment for recurrent glioblastoma.
Publisher: Rockefeller University Press
Date: 03-05-2004
DOI: 10.1084/JEM.20032177
Abstract: Effective immune surveillance is essential for maintaining protection and homeostasis of peripheral tissues. However, mechanisms controlling memory T cell migration to peripheral tissues such as the skin are poorly understood. Here, we show that the majority of human T cells in healthy skin express the chemokine receptor CCR8 and respond to its selective ligand I-309/CCL1. These CCR8+ T cells are absent in small intestine and colon tissue, and are extremely rare in peripheral blood, suggesting healthy skin as their physiological target site. Cutaneous CCR8+ T cells are preactivated and secrete proinflammatory cytokines such as tumor necrosis factor–α and interferon-γ, but lack markers of cytolytic T cells. Secretion of interleukin (IL)-4, IL-10, and transforming growth factor–β was low to undetectable, arguing against a strict association of CCR8 expression with either T helper cell 2 or regulatory T cell subsets. Potential precursors of skin surveillance T cells in peripheral blood may correspond to the minor subset of CCR8+CD25− T cells. Importantly, CCL1 is constitutively expressed at strategic cutaneous locations, including dermal microvessels and epidermal antigen-presenting cells. For the first time, these findings define a chemokine system for homeostatic T cell traffic in normal human skin.
Publisher: Cold Spring Harbor Laboratory
Date: 22-02-2023
DOI: 10.1101/2023.02.21.529331
Abstract: CAR-T cell therapies are being intensely investigated as a novel immunotherapy approach for glioblastoma (GBM), but so far clinical success has been limited. We recently described FAP as an ideal target antigen for GBM immunotherapy, with expression on tumor cells and tumor blood vessels occurring frequently in patients’ tumors but with very limited expression in healthy tissues. Here, we generated a novel FAP-targeting CAR with CD3ζ and CD28 signaling domains and tested the resulting CAR-T cells for their ability to lyse GBM cells in vitro and in vivo. FAP-CAR-T cells showed target specificity against model cell lines and exhibited potent cytotoxicity against patient-derived glioma neural stem (GNS) cells. Remarkably, complete destruction of tumor cells was observed even where the antigen was expressed by a minor subpopulation of cells, indicating a bystander killing mechanism. Using co-culture assays, we confirmed the ability of FAP-CAR-T cells to mediate bystander killing of antigen-negative tumor cells, but only after activation by antigen-expressing target cells. This bystander killing effect was at least partially mediated by soluble factors. We also observed that the non-transduced fraction of the CAR-T cell product could be activated via T cell-secreted IL-2 to mediate antigen-non-specific killing, further lifying the bystander effect. FAP-CAR-T cells controlled without overt toxicity the growth of subcutaneous tumors created using a mixture of antigen-negative and antigen-positive GBM cells. Together, our findings advance FAP as a leading candidate for clinical CAR-T cell therapy of GBM and highlight under-recognized antigen non-specific mechanisms that may contribute meaningfully to the antitumor activity of CAR-T cells.
Publisher: Cold Spring Harbor Laboratory
Date: 12-06-2022
DOI: 10.1101/2022.06.10.495719
Abstract: Accurate and precise delineation of gross tumour volumes remains a barrier to radiotherapy dose escalation and boost dosing in the treatment of solid tumours, such as prostate cancer. Magnetic resonance imaging of tumour molecular targets has the power to enable focal dose boosting, particularly when combined with technological advances such as MRI-LINAC. Fibroblast activation protein (FAP) is a transmembrane protein overexpressed in stromal components of % of epithelial carcinomas. Herein we compare targeted MRI of gold standard PSMA with FAP in the delineation of orthotopic tumours in a mouse model of prostate cancer. Control (no ligand), FAP and PSMA-targeting iron oxide nanoparticles were prepared with modification of an MRI agent (FerroTrace). Mice with orthotopic LNCaP tumours underwent T 2 -weighted 3D MRI 24 hours after intravenous injection of contrast agents. FAP and PSMA nanoparticles produced contrast enhancement on MRI when compared to control nanoparticles, which was most pronounced on the tumour periphery. FAP-targeted MRI increased the proportion of tumour contrast enhancing black pixels by 13.37% when compared to PSMA. Furthermore, analysis of changes in R2 values between healthy prostates and LNCaP tumours indicated an increase in contrast enhancing pixels in the tumour border of 15%, when targeting FAP, in contrast to PSMA This study demonstrates preclinical feasibility of PSMA and FAP-targeted MRI which can enable targeted image-guided focal therapy of localized prostate cancer.
Publisher: AME Publishing Company
Date: 12-2019
Publisher: Elsevier BV
Date: 2009
DOI: 10.1016/J.JIM.2008.09.023
Abstract: As more tumor antigens are discovered and as computer-guided T cell epitope prediction programs become more sophisticated, many potential T cell epitopes are synthesized and demonstrated to be antigenic in vitro. However, it is estimated that about 50% of such tumor antigen-specific T cells have not been demonstrated to recognize the naturally presented epitopes due to either technical difficulties, such as T cell cloning which is still challenging for many laboratories or the predicted T cell epitopes are not generated or not generated in sufficient amounts by the antigen processing machinery. However, to potentially identify clinically relevant vaccine candidate epitopes, it is essential to demonstrate natural antigen presentation. Here we combine the advantages of MHC tetramer and intracellular cytokine staining to sensitively detect natural antigen presentation by tumor cells for epitopes of interest. The novel method does not require T cell cloning or long-term T cell culture. Because the antigen-specific T cells are positively identified, this method is much less influenced by IFNgamma producing cells with unknown specificities and should be widely applicable.
Publisher: Elsevier BV
Date: 12-2013
DOI: 10.1038/KI.2013.306
Abstract: Recurring peritonitis reduces the effectiveness of peritoneal dialysis by increasing fibrosis and angiogenesis, ultimately causing ultrafiltration failure (UFF). Identifying the processes underlying UFF will provide new hope for patients with chronic kidney disease. Catar and colleagues demonstrate that transforming growth factor-β, tumor necrosis factor-α, and interleukin-1 synergize to significantly increase the production and release of vascular endothelial growth factor by mesothelial cells, which, if untreated, will promote peritoneal angiogenesis, leading to UFF.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2023
DOI: 10.1161/HYPERTENSIONAHA.123.21119
Abstract: Glioblastoma invasion is the primary mechanism responsible for its dismal prognosis and is the direct result of interactions between glioblastoma cells and the tumor vasculature. The dysregulated microvasculature in glioblastoma tumors and vessels co-opted from surrounding brain tissue support rapid tumor growth and are utilized as pathways for invasive cancer cells. Attempts to target the glioblastoma vasculature with antiangiogenic agents (eg, bevacizumab) have nonetheless shown limited and inconsistent efficacy, and the underlying causes of such heterogeneous responses remain unknown. Several studies have identified that patients with glioblastoma who develop hypertension following treatment with bevacizumab show significant improvement in overall survival compared with normotensive nonresponders. Here we review these findings and discuss the potential of hypertension as a biomarker for glioblastoma treatment response in in idual patients and the role of hypertension as a modulator of interactions between tumor cells and cells in the perivascular niche. We suggest that a better understanding of the actions of bevacizumab and hypertension at the cellular level will contribute to developing more effective personalized therapies that address glioblastoma tumor cell invasion.
Publisher: Wiley
Date: 05-04-1999
DOI: 10.1002/(SICI)1521-1878(199901)21:1<17::AID-BIES3>3.0.CO;2-4
Publisher: American Association for the Advancement of Science (AAAS)
Date: 27-10-2023
Publisher: Portland Press Ltd.
Date: 22-03-2019
DOI: 10.1042/BST20180444
Abstract: Glioblastoma is the deadliest form of brain cancer. Aside from inadequate treatment options, one of the main reasons glioblastoma is so lethal is the rapid growth of tumour cells coupled with continuous cell invasion into surrounding healthy brain tissue. Significant intra- and inter-tumour heterogeneity associated with differences in the corresponding tumour microenvironments contributes greatly to glioblastoma progression. Within this tumour microenvironment, the extracellular matrix profoundly influences the way cancer cells become invasive, and changes to extracellular (pH and oxygen levels) and metabolic (glucose and lactate) components support glioblastoma growth. Furthermore, studies on clinical s les have revealed that the tumour microenvironment is highly immunosuppressive which contributes to failure in immunotherapy treatments. Although technically possible, many components of the tumour microenvironment have not yet been the focus of glioblastoma therapies, despite growing evidence of its importance to glioblastoma malignancy. Here, we review recent progress in the characterisation of the glioblastoma tumour microenvironment and the sources of tumour heterogeneity in human clinical material. We also discuss the latest advances in technologies for personalised and in vitro preclinical studies using brain organoid models to better model glioblastoma and its interactions with the surrounding healthy brain tissue, which may play an essential role in developing new and more personalised treatments for this aggressive type of cancer.
Publisher: Future Medicine Ltd
Date: 03-2017
Abstract: Aim: Pilot clinical trial of NY-ESO-1 (ESO) protein in ISCOMATRIX™ adjuvant pulsed onto peripheral blood dendritic cells (PBDC), to ascertain feasibility, evaluate toxicity and assess induction of ESO-specific immune responses. Patients & methods: Eligible participants had resected cancers expressing ESO or LAGE-1 and were at high risk of relapse. PBDC were produced using CliniMACS ® plus, with initial depletion of CD1c + B cells followed by positive selection of CD1c + PBDC. Patients received three intradermal vaccinations of ESO/IMX-pulsed PBDC at 4-week intervals. Results: The process was feasible and safe. No vaccine-induced immune responses were detected. Assays of immunomodulatory cells did not correlate with outcomes. One patient had a long lasting complete remission. Conclusion: This method was feasible and safe but was minimally immunogenic.
Publisher: Impact Journals, LLC
Date: 11-03-2015
Abstract: The dynamic balance of cellular sphingolipids, the sphingolipid rheostat, is an important determinant of cell fate, and is commonly deregulated in cancer. Sphingosine 1-phosphate is a signaling molecule with anti-apoptotic, pro-proliferative and pro-angiogenic effects, while conversely, ceramide and sphingosine are pro-apoptotic. The sphingosine kinases (SKs) are key regulators of this sphingolipid rheostat, and are attractive targets for anti-cancer therapy. Here we report a first-in-class ATP-binding site-directed small molecule SK inhibitor, MP-A08, discovered using an approach of structural homology modelling of the ATP-binding site of SK1 and in silico docking with small molecule libraries. MP-A08 is a highly selective ATP competitive SK inhibitor that targets both SK1 and SK2. MP-A08 blocks pro-proliferative signalling pathways, induces mitochondrial-associated apoptosis in a SK-dependent manner, and reduces the growth of human lung adenocarcinoma tumours in a mouse xenograft model by both inducing tumour cell apoptosis and inhibiting tumour angiogenesis. Thus, this selective ATP competitive SK inhibitor provides a promising candidate for potential development as an anti-cancer therapy, and also, due to its different mode of inhibition to other known SK inhibitors, both validates the SKs as targets for anti-cancer therapy, and represents an important experimental tool to study these enzymes.
No related grants have been discovered for Lisa Ebert.