Induction of immune tolerance: a role for Natural killer T lymphocytes?
The ability of the immune system to distinguish between harmful and harmless antigens is essential for mounting protective immune responses and preventing the induction of pathology. Tolerance is a mechanism that prevents or suppresses potentially injurious immune responses. Natural killer T (NKT) lymphocytes, a subset of regulatory T lymphocytes, can induce pro-inflammatory or anti-inflammatory immune responses. This subset of cells appears to be crucial for induction of tolerance by several immune-modulatory interventions; these include immune manipulations in the setting of transplantation, induction of tolerance by introduction of antigen into immune-privileged sites, and oral administration of disease-associated-antigen. The ability to predict whether tolerance or immunity will be generated in a given situation is essential for development of NKT lymphocyte-based immune-modulatory treatments. The role of NKT lymphocytes in these settings, and the requirements for development of tolerance, rather than immunity, are discussed.
Margalit
Maya
M
Liver Unit, Department of Medicine, Hebrew University-Hadassah Medical Center, Jerusalem, Israel.
Ilan
Yaron
Y
D000818:Animals; D006801:Humans; D007108:Immune Tolerance / Q000276:immunology*; D007694:Killer Cells, Natural / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*