T cell growth and differentiation induced by interleukin-HP1/IL-6, the murine hybridoma/plasmacytoma growth factor.
Interleukin-HP1 (HP1)/IL-6 is a 25-30-kD protein produced by macrophages, fibroblasts, and certain T cell lines. It was originally identified as a mouse growth factor for B cell hybridomas and plasmacytomas, and was recently shown to stimulate growth and differentiation of normal B cells. Here we demonstrate that, in the presence of lectins or anti-T cell receptor antibodies, HP1/IL-6 has a growth factor activity equivalent to that of IL-2 for mature thymic and peripheral T cells of both the L3T4+ and Lyt-2+ subsets. Contrary to IL-2 and IL-4, HP1/IL-6 was, however, not capable of supporting the growth of established T cell lines. In addition to its effects on T cell proliferation, HP1/IL-6 also enhanced the differentiation of mouse cytolytic T cell precursors in primary allogeneic mixed lymphocyte cultures. Fractionation of responding cell populations indicated that HP1/IL-6 was capable of restoring the response of accessory cell-depleted T cells to Con A. This observation suggests that the production of HP1/IL-6 by macrophages could, at least partly, explain their role in polyclonal T cell activation.
Uyttenhove
C
C
Ludwig Institute for Cancer Research, Brussels Branch, Belgium.
Coulie
P G
PG
Van Snick
J
J
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D004357:Drug Synergism; D005260:Female; D015850:Interleukin-6; D007378:Interleukins / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D010835:Phytohemagglutinins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects*; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000187:drug effects; D006377:T-Lymphocytes, Helper-Inducer / Q000187:drug effects
D015850:Interleukin-6; D007378:Interleukins; D010835:Phytohemagglutinins