Regulatory T Cells and Organ Transplantation

Sir William Dunn School of Pathology, South Parks Road, Oxford OX13RE, UK.
Seminars in Immunology (Impact Factor: 5.17). 05/2004; 16(2):119-26. DOI: 10.1016/j.smim.2003.12.007
Source: PubMed


Empirical studies attempting to explain tolerance to transplanted tissues have demonstrated a regulatory role for CD4+ T-cells. We here propose that regulatory T-cells mediating transplantion tolerance comprise two sets which can functionally complement each other. The CD4+CD25+ "natural regulator" arises in the thymus, and is preoccupied with self-antigens expressed at sites of inflammation. The second, comprising both CD4+CD25+ (FoxP3+) and CD4+CD25- Tr1-like cells are induced by persistent danger-free antigen in the periphery. The role of these cells is to moderate immune responses to prevent tissue destruction while allowing microbial elimination.

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