Epidermotropic lymphomas. Introductory immunological remarks.

The immune system is reviewed. Its ontogeny, differentiation and localization are discussed. Although cellular immunity mainly depends on T cells (thymus-derived) and humoral immunity depends on B cells (bone-marrow-derived), there are many interactions between these two systems. The role of T cells, in the production of antibodies, appears to be mainly regulatory. Various subpopulations of T cells are mentioned. The interactions between B cells and macrophages are described, as well as the markers of human T and B cells.