Using immune system to treat cancer is a promising avenue. A regulatory CD4+
cell population is known to modulates CD8+ T cell immunity. Through many
experiments, it was shown that CD4+ cells that expressed CD25 from mice with
tumors inhibit CD8+ T cell mediated anti-tumor responses. These regulatory cells
effect T cells and anti- tumor responses. When using with peptide or dendritic cell
vaccine, blocking or depletion of the regulatory cells hightened the effectiveness of
tumor vaccine. Numerous regulatory cells capable of inhibiting in vitro and in vivo
functions of T cells have been found in several different types of cancer patients.
Further, the therapeutic efficacy of adoptively transferred ex vivo expanded
tumor-specific T cells was enhanced when endogenous lymphocytes were depleted
prior to the T cell transfer. Taken together, these studies have shown that
CD4+regulatory cells suppress CD8+ T cell immunity, and that it can be restored
upon eliminating the regulatory cells.
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Using the immune system to treat cancer is a promising avenue of research.
Regulatory CD4+ T cells are known to suppress CD8+ T cell mediated immunity.
More specifically, numerous studies have shown that CD4+CD25+ T cells from
tumor-bearing mice can inhibit CD8+ T cell mediated anti-tumor responses. Large
numbers of regulatory T cells have been found infiltrating a variety of human
tumors. When used with peptide or dendritic cell vaccines, neutralization or
depletion of these CD4+ CD25+ regulatory cells has heightened the vaccines'
effectiveness. Further, the therapeutic efficacy of adoptively transferred, ex vivo
expanded tumor-specific T cells was enhanced when endogenous CD25+ [Note to
authors: was this your intended meaning?] lymphocytes were depleted prior to T
cell transfer. Taken together, these studies have demonstrated that CD4+
regulatory T cells suppress CD8+ T cell immunity, and that elimination of
regulatory cells can restore protective immune responses.
Word count: 138
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