title: Immune regulator vitamin A and T cell death.
abstract: Proper regulation of T cell death is of vital importance for the function of the immune system. Positive and negative selection of developing T cells in the thymus ensures the survival of only those T cells that can recognize peptides presented by self-MHC molecules and at the same time not respond to self-antigens, and thus, T cell death within the thymus is instrumental in shaping the mature T cell repertoire. The death of activated peripheral T cells is crucial for processes such as down-modulation of immune responses after clearance of infectious agents, peripheral tolerance, and maintenance of immune-privileged sites. These processes are largely proceeding due to the enhanced susceptibility of activated T cells to spontaneous, activation-, and Fas-induced apoptosis. The active metabolite of the immune regulator vitamin A, retinoic acid, has been reported to influence various types of apoptotic processes in both thymocytes and activated peripheral T cells. This chapter gives an overview of, and discusses the reported effects of vitamin A on spontaneous and activation-induced cell death of thymocytes and mature T cells, as well as on Fas-induced T cell death.
authors.affiliation: Centre for Molecular Medicine Norway, Nordic EMBL Partnership, University of Oslo, Oslo, Norway.
authors.forename: Nikolai
authors.initials: N
authors.lastname: Engedal
mesh_terms: D000818:Animals; D016923:Cell Death; D006801:Humans; D007107:Immune System / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology*; D014801:Vitamin A / Q000502:physiology*
chemical_list: D014801:Vitamin A