ORCID Profile
0000-0001-6556-6855
Current Organisation
University of South Australia
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Cold Spring Harbor Laboratory
Date: 29-06-2020
DOI: 10.1101/2020.06.29.177196
Abstract: Compensating in classical flow cytometry or unmixing in spectral systems is an unavoidable challenge in the data analysis of fluorescence-based flow cytometry. In both cases, spillover coefficients are estimated for each fluorophore using single-color controls. This approach has remained essentially unchanged since its inception, and is increasingly limited in its ability to deal with high-parameter flow cytometry. Here, we present AutoSpill, a novel approach for calculating spillover coefficients or spectral signatures of fluorophores. The approach combines automated gating of cells, calculation of an initial spillover matrix based on robust linear regression, and iterative refinement to reduce error. Moreover, autofluorescence can be compensated out, by processing it as an endogenous dye in an unstained control. AutoSpill uses single-color controls and is compatible with common flow cytometry software, but it differs in two key aspects from current methods: (1) it is much less demanding in the preparation of controls, as it does not require the presence of well-defined positive and negative populations, and (2) it does not require manual tuning of the spillover matrix, as the algorithm iteratively computes the tuning, producing an optimal compensation matrix. Another algorithm, AutoSpread, complements this approach, providing a robust estimate of the Spillover Spreading Matrix (SSM), while avoiding the need for well-defined positive and negative populations. Together, AutoSpill and AutoSpread provide a superior solution to the problem of fluorophore spillover, allowing simpler and more robust workflows in high-parameter flow cytometry.
Publisher: Elsevier BV
Date: 02-2016
DOI: 10.1016/J.TIM.2015.11.003
Abstract: Here, the use of pharmacological agents to reverse HIV-1 latency will be explored as a therapeutic strategy towards a cure. However, while clinical trials of latency-reversing agents LRAs) have demonstrated their ability to increase production of latent HIV-1, such interventions have not had an effect on the size of the latent HIV-1 reservoir. Plausible explanations for this include insufficient host immune responses against virus-expressing cells, the presence of escape mutations in archived virus, or an insufficient scale of latency reversal. Importantly, these early studies of LRAs were primarily designed to investigate their ability to perturb the state of HIV-1 latency using the absence of an impact on the size of the HIV-1 reservoir to discard their potential inclusion in curative strategies would be erroneous and premature.
Publisher: Public Library of Science (PLoS)
Date: 17-09-2015
Publisher: Elsevier BV
Date: 10-2014
Publisher: Public Library of Science (PLoS)
Date: 02-07-2015
Publisher: Informa UK Limited
Date: 24-03-2016
Publisher: Elsevier BV
Date: 08-2020
Publisher: Rockefeller University Press
Date: 14-06-2022
DOI: 10.1084/JEM.20212391
Abstract: Interleukin 2 (IL-2) is a key homeostatic cytokine, with therapeutic applications in both immunogenic and tolerogenic immune modulation. Clinical use has been h ered by pleiotropic functionality and widespread receptor expression, with unexpected adverse events. Here, we developed a novel mouse strain to ert IL-2 production, allowing identification of contextual outcomes. Network analysis identified priority access for Tregs and a competitive fitness cost of IL-2 production among both Tregs and conventional CD4 T cells. CD8 T and NK cells, by contrast, exhibited a preference for autocrine IL-2 production. IL-2 sourced from dendritic cells lified Tregs, whereas IL-2 produced by B cells induced two context-dependent circuits: dramatic expansion of CD8+ Tregs and ILC2 cells, the latter driving a downstream, IL-5–mediated, eosinophilic circuit. The source-specific effects demonstrate the contextual influence of IL-2 function and potentially explain adverse effects observed during clinical trials. Targeted IL-2 production therefore has the potential to lify or quench particular circuits in the IL-2 network, based on clinical desirability.
Publisher: American Astronomical Society
Date: 07-2023
Abstract: We report observations of a remarkable major axes alignment nearly parallel to the Galactic plane of 5 σ significance for a subset of bulge “planetary nebulae” (PNe) that host, or are inferred to host, short-period binaries. Nearly all are bipolar. It is solely this specific PN population that accounts for the much weaker statistical alignments previously reported for the more general bulge PNe. It is clear evidence of a persistent, organized process acting on a measurable parameter at the heart of our galaxy over perhaps cosmologically significant periods of time for this very particular PN s le. Stable magnetic fields are currently the only plausible mechanism that could affect multiple binary star orbits as revealed by the observed major axes orientations of their eventual PNe. Ex les are fed into the current bulge PN population at a rate determined by their formation history and mass range of their binary stellar progenitors.
Publisher: Springer Science and Business Media LLC
Date: 26-05-2022
DOI: 10.1038/S41590-022-01208-Z
Abstract: The ability of immune-modulating biologics to prevent and reverse pathology has transformed recent clinical practice. Full utility in the neuroinflammation space, however, requires identification of both effective targets for local immune modulation and a delivery system capable of crossing the blood–brain barrier. The recent identification and characterization of a small population of regulatory T (T reg ) cells resident in the brain presents one such potential therapeutic target. Here, we identified brain interleukin 2 (IL-2) levels as a limiting factor for brain-resident T reg cells. We developed a gene-delivery approach for astrocytes, with a small-molecule on-switch to allow temporal control, and enhanced production in reactive astrocytes to spatially direct delivery to inflammatory sites. Mice with brain-specific IL-2 delivery were protected in traumatic brain injury, stroke and multiple sclerosis models, without impacting the peripheral immune system. These results validate brain-specific IL-2 gene delivery as effective protection against neuroinflammation, and provide a versatile platform for delivery of erse biologics to neuroinflammatory patients.
Publisher: eLife Sciences Publications, Ltd
Date: 02-11-2021
DOI: 10.7554/ELIFE.70554
Abstract: Antibody production following vaccination can provide protective immunity to subsequent infection by pathogens such as influenza viruses. However, circumstances where antibody formation is impaired after vaccination, such as in older people, require us to better understand the cellular and molecular mechanisms that underpin successful vaccination in order to improve vaccine design for at-risk groups. Here, by studying the breadth of anti-haemagglutinin (HA) IgG, serum cytokines, and B and T cell responses by flow cytometry before and after influenza vaccination, we show that formation of circulating T follicular helper (cTfh) cells was associated with high-titre antibody responses. Using Major Histocompatability Complex (MHC) class II tetramers, we demonstrate that HA-specific cTfh cells can derive from pre-existing memory CD4 + T cells and have a erse T cell receptor (TCR) repertoire. In older people, the differentiation of HA-specific cells into cTfh cells was impaired. This age-dependent defect in cTfh cell formation was not due to a contraction of the TCR repertoire, but rather was linked with an increased inflammatory gene signature in cTfh cells. Together, this suggests that strategies that temporarily d en inflammation at the time of vaccination may be a viable strategy to boost optimal antibody generation upon immunisation of older people.
Publisher: Springer Science and Business Media LLC
Date: 05-06-2017
DOI: 10.1038/NCOMMS15632
Abstract: Interleukin 17-producing γδ T (γδT17) cells have unconventional trafficking characteristics, residing in mucocutaneous tissues but also homing into inflamed tissues via circulation. Despite being fundamental to γδT17-driven early protective immunity and exacerbation of autoimmunity and cancer, migratory cues controlling γδT17 cell positioning in barrier tissues and recruitment to inflammatory sites are still unclear. Here we show that γδT17 cells constitutively express chemokine receptors CCR6 and CCR2. While CCR6 recruits resting γδT17 cells to the dermis, CCR2 drives rapid γδT17 cell recruitment to inflamed tissues during autoimmunity, cancer and infection. Downregulation of CCR6 by IRF4 and BATF upon γδT17 activation is required for optimal recruitment of γδT17 cells to inflamed tissue by preventing their sequestration into uninflamed dermis. These findings establish a lymphocyte trafficking model whereby a hierarchy of homing signals is prioritized by dynamic receptor expression to drive both tissue surveillance and rapid recruitment of γδT17 cells to inflammatory lesions.
Publisher: Public Library of Science (PLoS)
Date: 20-02-2014
Publisher: Elsevier BV
Date: 2023
Publisher: Rockefeller University Press
Date: 14-04-2020
DOI: 10.1084/JEM.20190634
Abstract: Current immunotherapies involving CD8+ T cell responses show remarkable promise, but their efficacy in many solid tumors is limited, in part due to the low frequency of tumor-specific T cells in the tumor microenvironment (TME). Here, we identified a role for host atypical chemokine receptor 4 (ACKR4) in controlling intratumor T cell accumulation and activation. In the absence of ACKR4, an increase in intratumor CD8+ T cells inhibited tumor growth, and nonhematopoietic ACKR4 expression was critical. We show that ACKR4 inhibited CD103+ dendritic cell retention in tumors through regulation of the intratumor abundance of CCL21. In addition, preclinical studies indicate that ACKR4 and CCL21 are potential therapeutic targets to enhance responsiveness to immune checkpoint blockade or T cell costimulation.
Publisher: Rockefeller University Press
Date: 25-07-2022
Publisher: Wiley
Date: 2023
DOI: 10.1002/CPZ1.678
Publisher: Springer Science and Business Media LLC
Date: 17-05-2021
DOI: 10.1038/S41467-021-23126-8
Abstract: Compensating in flow cytometry is an unavoidable challenge in the data analysis of fluorescence-based flow cytometry. Even the advent of spectral cytometry cannot circumvent the spillover problem, with spectral unmixing an intrinsic part of such systems. The calculation of spillover coefficients from single-color controls has remained essentially unchanged since its inception, and is increasingly limited in its ability to deal with high-parameter flow cytometry. Here, we present AutoSpill, an alternative method for calculating spillover coefficients. The approach combines automated gating of cells, calculation of an initial spillover matrix based on robust linear regression, and iterative refinement to reduce error. Moreover, autofluorescence can be compensated out, by processing it as an endogenous dye in an unstained control. AutoSpill uses single-color controls and is compatible with common flow cytometry software. AutoSpill allows simpler and more robust workflows, while reducing the magnitude of compensation errors in high-parameter flow cytometry.
Publisher: Springer Science and Business Media LLC
Date: 15-03-2011
Publisher: American Society for Microbiology
Date: 05-2016
DOI: 10.1128/JVI.00222-16
Abstract: Toll-like receptor (TLR) agonists are potent enhancers of innate antiviral immunity and may also reverse HIV-1 latency. Therefore, TLR agonists have a potential role in the context of a “shock-and-kill” approach to eradicate HIV-1. Our extensive preclinical evaluation suggests that a novel TLR9 agonist, MGN1703, may indeed perform both functions in an HIV-1 eradication trial. Peripheral blood mononuclear cells (PBMCs) from aviremic HIV-1-infected donors on antiretroviral therapy (ART) that were incubated with MGN1703 ex vivo exhibited increased secretion of interferon alpha (IFN-α) ( P = 0.005) and CXCL10 ( P = 0.0005) in culture supernatants. Within the incubated PBMC pool, there were higher proportions of CD69-positive CD56 dim CD16 + NK cells ( P = 0.001) as well as higher proportions of CD107a-positive ( P = 0.002) and IFN-γ-producing ( P = 0.038) NK cells. Incubation with MGN1703 also increased the proportions of CD69-expressing CD4 + and CD8 + T cells. Furthermore, CD4 + T cells within the pool of MGN1703-incubated PBMCs showed enhanced levels of unspliced HIV-1 RNA ( P = 0.036). Importantly, MGN1703 increased the capacity of NK cells to inhibit virus spread within a culture of autologous CD4 + T cells assessed by using an HIV-1 p24 enzyme-linked immunosorbent assay (ELISA) ( P = 0.03). In conclusion, we show that MGN1703 induced strong antiviral innate immune responses, enhanced HIV-1 transcription, and boosted NK cell-mediated suppression of HIV-1 infection in autologous CD4 + T cells. These findings support clinical testing of MGN1703 in HIV-1 eradication trials. IMPORTANCE We demonstrate that MGN1703 (a TLR9 agonist currently undergoing phase 3 clinical testing for the treatment of metastatic colorectal cancer) induces potent antiviral responses in immune effector cells from HIV-1-infected in iduals on suppressive antiretroviral therapy. The significantly improved safety and tolerability profiles of MGN1703 versus TLR9 agonists of the CpG-oligodeoxynucleotide (CpG-ODN) family are due to its novel “dumbbell-shape” structure made of covalently closed, natural DNA. In our study, we found that incubation of peripheral blood mononuclear cells with MGN1703 results in natural killer cell activation and increased natural killer cell function, which significantly inhibited the spread of HIV in a culture of autologous CD4 + T cells. Furthermore, we discovered that MGN1703-mediated activation can enhance HIV-1 transcription in CD4 + T cells, suggesting that this molecule may serve a dual purpose in HIV-1 eradication therapy: enhanced immune function and latency reversal. These findings provide a strong preclinical basis for the inclusion of MGN1703 in an HIV eradication clinical trial.
Publisher: Wiley
Date: 24-04-2020
DOI: 10.1111/IMCB.12332
Publisher: Public Library of Science (PLoS)
Date: 26-04-2013
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2016
Publisher: Hindawi Limited
Date: 2015
DOI: 10.1155/2015/120605
Abstract: Intestinal CD4 + T cell depletion is rapid and profound during early HIV-1 infection. This leads to a compromised mucosal barrier that prompts chronic systemic inflammation. The preferential loss of intestinal T helper 17 (Th17) cells in HIV-1 disease is a driver of the damage within the mucosal barrier and of disease progression. Thus, understanding the effects of new therapeutic strategies in the intestines has high priority. Histone deacetylase (HDAC) inhibitors (e.g., panobinostat) are actively under investigation as potential latency reversing agents in HIV eradication studies. These drugs have broad effects that go beyond reactivating virus, including modulation of immune pathways. We examined colonic biopsies from ART suppressed HIV-1 infected in iduals (clinicaltrials.gov: NCT01680094 ) for the effects of panobinostat on intestinal T cell activation and on inflammatory cytokine production. We compared biopsy s les that were collected before and during oral panobinostat treatment and observed that panobinostat had a clear biological impact in this anatomical compartment. Specifically, we observed a decrease in CD69 + intestinal lamina propria T cell frequency and increased IL-17A mRNA expression in the intestinal epithelium. These results suggest that panobinostat therapy may influence the restoration of mucosal barrier function in these patients.
Publisher: Springer Science and Business Media LLC
Date: 29-10-2015
DOI: 10.1038/NCOMMS9644
Abstract: IL-17-producing helper T (Th17) cells are critical for host defense against extracellular pathogens but also drive numerous autoimmune diseases. Th17 cells that differ in their inflammatory potential have been described including IL-10-producing Th17 cells that are weak inducers of inflammation and highly inflammatory, IL-23-driven, GM-CSF/IFNγ-producing Th17 cells. However, their distinct developmental requirements, functions and trafficking mechanisms in vivo remain poorly understood. Here we identify a temporally regulated IL-23-dependent switch from CCR6 to CCR2 usage by developing Th17 cells that is critical for pathogenic Th17 cell-driven inflammation in experimental autoimmune encephalomyelitis (EAE). This switch defines a unique in vivo cell surface signature (CCR6 − CCR2 + ) of GM-CSF/IFNγ-producing Th17 cells in EAE and experimental persistent extracellular bacterial infection, and in humans. Using this signature, we identify an IL-23/IL-1/IFNγ/TNFα/T-bet/Eomesodermin-driven circuit driving GM-CSF/IFNγ-producing Th17 cell formation in vivo . Thus, our data identify a unique cell surface signature, trafficking mechanism and T-cell intrinsic regulators of GM-CSF/IFNγ-producing Th17 cells.
Publisher: Cold Spring Harbor Laboratory
Date: 02-03-2022
DOI: 10.1101/2022.02.28.482297
Abstract: The ability of immune-modulating biologics to prevent and reverse pathology has transformed recent clinical practice. Full utility in the neuroinflammation space, however, requires identification of both effective targets for local immune-modulation and a delivery system capable of crossing the blood-brain-barrier. The recent identification and characterization of a small population of regulatory T cells (Tregs) resident in the brain presents one such potential therapeutic target. Here we identified brain IL2 levels as a limiting factor for brain-resident Tregs. We developed a gene-delivery approach for astrocytes, with a small-molecule on-switch to allow temporal control, and enhanced production in reactive astrocytes to spatially-direct delivery to inflammatory sites. Mice with brain-specific IL2 delivery were protected from traumatic brain injury, stroke and multiple sclerosis models, without impacting the peripheral immune system. These results validate brain-specific IL2 gene-delivery as effective protection against neuroinflammation, and provide a versatile platform for delivery of erse biologics to neuroinflammatory patients.
Publisher: Springer Science and Business Media LLC
Date: 13-05-2020
Publisher: Springer Science and Business Media LLC
Date: 08-09-2016
DOI: 10.1038/NCOMMS12731
Abstract: The ‘shock and kill’ approach to cure human immunodeficiency virus (HIV) includes transcriptional induction of latent HIV-1 proviruses using latency-reversing agents (LRAs) with targeted immunotherapy to purge infected cells. The administration of LRAs (panobinostat or vorinostat) to HIV-1-infected in iduals on antiretroviral therapy induces a significant increase in cell-associated unspliced (CA-US) HIV-1 RNA from CD4 + T cells. However, it is important to discern whether the increases in CA-US HIV-1 RNA are due to limited or broad activation of HIV-1 proviruses. Here we use single-genome sequencing to find that the RNA transcripts observed following LRA administration are genetically erse, indicating activation of transcription from an extensive range of proviruses. Defective sequences are more frequently found in CA HIV-1 RNA than in HIV-1 DNA, which has implications for developing an accurate measure of HIV-1 reservoir size. Our findings provide insights into the effects of panobinostat and vorinostat as LRAs for latent HIV-1.
Publisher: Elsevier BV
Date: 2016
Publisher: Cold Spring Harbor Laboratory
Date: 20-12-2020
DOI: 10.1101/2020.12.18.423431
Abstract: Interleukin 2 (IL-2) is a key homeostatic cytokine, with potential therapeutic applications in both immunogenic and tolerogenic immune modulation. Clinical application has been h ered by pleiotropic functionality and wide-spread receptor expression, with unexpected adverse events during trials. To characterize the IL-2 homeostatic network, we developed a novel mouse strain allowing IL-2 production to be erted. Rewiring of IL-2 production to erse leukocyte sources allowed the identification of contextual influences over IL-2 impact. Network analysis identified a priority access for Tregs, and a competitive fitness cost induced among both Tregs and conventional CD4 T cells for IL-2 production. CD8 T cells and NK cells, by contrast, exhibited a preference for autocrine IL-2 production. IL-2 sourced from dendritic cells lified the Treg circuit, while IL-2 produced by B cells induced two context-dependent circuits: dramatic expansion of CD8 + Tregs and ILC2 cells. The former was associated with an unexpected concentration of rare CD8 + Tregs in B cell zones, while the latter drove a downstream, IL-5-mediated, eosinophilic circuit. The source-specific effects demonstrate the contextual influence of IL-2 function and potentially explain unexpected adverse effects observed during clinical trials of exogenous IL-2. Targeted IL-2 production therefore has the potential to lify or quench particular circuits in the IL-2 network, based on clinical desirability.
Publisher: Elsevier
Date: 2017
DOI: 10.1016/BS.AI.2017.03.001
Abstract: CD4
Publisher: Informa UK Limited
Date: 14-05-2013
DOI: 10.4161/HV.23800
Publisher: Springer Science and Business Media LLC
Date: 2015
Publisher: Springer Science and Business Media LLC
Date: 31-01-2017
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 13-03-2016
Publisher: American Association for the Advancement of Science (AAAS)
Date: 11-2019
DOI: 10.1126/SCIIMMUNOL.AAY6039
Abstract: Characterizing MAIT cell development led to the identification of key regulators that specify MAIT cell fate in the thymus.
Publisher: Elsevier BV
Date: 06-2013
DOI: 10.1016/J.CYTOGFR.2013.03.001
Abstract: The chemokine receptor CCR7 and its ligands CCL19 and CCL21 control a erse array of migratory events in adaptive immune function. Most prominently, CCR7 promotes homing of T cells and DCs to T cell areas of lymphoid tissues where T cell priming occurs. However, CCR7 and its ligands also contribute to a multitude of adaptive immune functions including thymocyte development, secondary lymphoid organogenesis, high affinity antibody responses, regulatory and memory T cell function, and lymphocyte egress from tissues. In this survey, we summarise the role of CCR7 in adaptive immunity and describe recent progress in understanding how this axis is regulated. In particular we highlight CCX-CKR, which scavenges both CCR7 ligands, and discuss its emerging significance in the immune system.
Publisher: Elsevier BV
Date: 10-2016
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2010
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 19-06-2015
Publisher: Wiley
Date: 11-2022
DOI: 10.1002/CPZ1.589
Abstract: Recent advances in flow cytometry have allowed high‐dimensional characterization of biological phenomena, enabling breakthroughs in a multitude of fields. Despite the appreciation of the unique properties of antigens and fluorophores in high‐parameter panel design, staining conditions are often standardized for short surface stains, regardless of antibody affinity or antigen accessibility. Here, we demonstrate how increasing antibody incubation times can lead to substantial improvements in sensitivity, maintaining specificity, and reducing background, while also significantly reducing the costs of high‐parameter cytometry panels. Furthermore, overnight staining reduces the influence of interexperimental variability, assisting accurate pooling over experiments over extended time courses. We provide guidance on how to optimize staining conditions for erse antigens, including how different fixation strategies can affect epitope accessibility. Overnight staining can thus substantially improve the resolution, repeatability, and cost‐effectiveness of high‐parameter cytometry. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. This article was corrected on 18 January 2023. See the end of the full text for details.
Location: United Kingdom of Great Britain and Northern Ireland
No related grants have been discovered for Carly Whyte.