Profiles of lymphokine activities and helper function for IgE in human T cell clones

Abstract

A large panel of phytohemagglutinin (PHA)-induced T cell clones (690 in total), established from four different human lymphoid tissues (peripheral blood, tonsils, lymph nodes and spleens) by a high-efficiency cloning technique, was characterized according to their pattern of lymphokine production. The majority of both CD4+ and CD8+ clones from all lymphoid tissues produced interleukin (IL) 2 and/or interferon (IFN)-gamma in response to 24-h stimulation with PHA. In contrast, higher proportions of IL 4-producing clones were found among CD4+ clones from tonsils and spleens than from peripheral blood and lymph nodes, whereas only a minority of CD8+ clones from all lymphoid tissues were found to produce IL 4. It was not possible to divide the CD4+ (helper/inducer) clones on the basis of their pattern of lymphokine activity into two clear-cut groups analogous to Th1 and Th2 helper clones described in mice. Although 21 out of 503 (4%) CD4+ T cell clones produced IL 4, but not IFN-gamma or IL 2, and 208 (41%) produced IL 2 and/or IFN-gamma, but not IL 4, a total number of 185 (37%) CD4+ clones showed the ability to produce IL 4 plus IL 2 and/or IFN-gamma. All types of CD4+ T cells (as classified according to their pattern of lymphokine activity) provided help for IgG production in allogeneic B cells. In contrast, helper function for IgE was detectable only among the IL 4-producing clones.(ABSTRACT TRUNCATED AT 250 WORDS)