Gillian C. Harcourt

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Containment of hepatitis C virus (HCV) and other chronic human viral infections is associated with persistence of virus-specific CD4 T cells, but ex vivo characterization of circulating CD4 T cells has not been achieved. To further define the phenotype and function of these cells, we developed a novel approach for the generation of tetrameric forms of MHC(More)
Hepatitis C virus (HCV) becomes persistent in the majority of infected individuals. In doing so, the virus evades host adaptive immune responses, although the mechanisms responsible in this evasion are not clear. Several groups have demonstrated weak or absent HCV-specific CD4+ T cell responses during chronic HCV infection using proliferation assays and,(More)
Mutations in human immunodeficiency virus (HIV) cluster in cytotoxic T lymphocyte (CTL) epitopes (Phillips, R. E. et al., Nature 1991. 354: 453) and are subject to immune-mediated positive selection (Price, D. A. et al., Proc. Natl. Acad. Sci. USA 1997. 94: 1890). We studied the effects of naturally occurring mutations in the HIV-1 p17 Gag HLA A2 restricted(More)
Hepatitis C virus (HCV) infection is very common worldwide, but has a broad range of outcomes. A minority of patients are able to clear infection spontaneously, and this is thought to be due to the emergence and maintenance of effective cell-mediated immunity, particularly CD4+ T lymphocyte responses. Furthermore, genetic studies have indicated that HLA(More)
Hepatitis C virus (HCV) readily sets up a persistent infection and is a major cause of liver disease worldwide. Interferon alfa and ribavirin therapy lead to sustained clearance of virus in 31% to 64% of patients with type 1 and non-type 1 genotypes, respectively. It is not clear to what extent these drugs act directly to reduce HCV replication, or(More)
Effective long-term antiviral immunity requires specific cytotoxic T lymphocytes and CD4(+) T lymphocyte help. Failure of these helper responses can be a principle cause of viral persistence. We sought evidence that variation in HIV-1 CD4(+) T helper epitopes might contribute to this phenomenon. To determine this, we assayed fresh peripheral blood(More)
Hepatitis C virus (HCV) readily causes a persistent infection, although some individuals spontaneously control infection. 'Successful' immune responses appear to be multi-specific and sustained-including a major role for CD4(+)T cells. Some antiviral CD8(+)T cells show reduced capacity to secrete antiviral cytokines either temporarily ('stunning') or in the(More)
BACKGROUND Human immunodeficiency virus/hepatitis C virus (HIV/HCV) coinfection is a common and complex clinical problem in which loss of immunological control of HCV occurs, with increased HCV viral load and more aggressive liver disease. Cellular immune responses, particularly secretion of interferon gamma (IFN-gamma) appear to be important in the control(More)
Helper T lymphocytes recognize fragments of foreign (or self) antigens in the peptide-binding clefts of major histocompatibility complex class II molecules; their activation is a crucial step in the induction of many immune and autoimmune responses. While studying the latter, we raised a T-cell line from the thymus of a myasthenia gravis patient against(More)