Intraepithelial lymphocytes of the intestinal mucosa: curiouser and curiouser.
Intraepithelial lymphocytes (IEL) of the intestine are discussed in light of recent findings concerning their ontogeny and T cell receptor expression. IEL are distinct from other peripheral T cells in many aspects, including their homing abilities and their phenotypic characteristics. IEL that express the gamma/delta T cell receptor are singular in that the thymus is not required for their maturation or for the selection of certain T cell receptor variable regions. Despite recent efforts, the in vivo function of IEL with gamma/delta T cell receptors remains unclear. Overall, IEL and the associated mucosa represent a complex lymphoid organ that will be the object of much future experimentation.
Lefrançois
L
L
Department of Cell Biology, Upjohn Company, Kalamazoo, MI 49001.
D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D004848:Epithelium / Q000276:immunology; D006801:Humans; D007413:Intestinal Mucosa / Q000276:immunology*; D011948:Receptors, Antigen, T-Cell / Q000032:analysis* / Q000235:genetics; D016692:Receptors, Antigen, T-Cell, gamma-delta; D013601:T-Lymphocytes / Q000276:immunology* / Q000502:physiology
D015703:Antigens, CD; D011948:Receptors, Antigen, T-Cell; D016692:Receptors, Antigen, T-Cell, gamma-delta