Induction of IL-2 receptor expression and proliferation of T cell clones by a novel cytokine(s).
We found a unique T cell IL-2 receptor (IL-2R)3-inducing activity in the supernatant (SN) of the TH1 clone stimulated with antigen on spleen cells as antigen-presenting cells (APC). We have tentatively named this activity the IL-2R-inducing factor (IL-2RIF) and have characterized the activity. The SN induced IL-2R and proliferation of TH1 clones stimulated with B cell APC, which could not induce IL-2R in the absence of the SN. Other known cytokines were examined for a IL-2RIF activity; however, none of cytokines examined exerted a similar activity. Moreover, the neutralizing antibodies against the known cytokines tested did not block the IL-2RIF activity in the SN. When TH1 clones were stimulated with immobilized anti-CD3 or with fixed B cell APC in the presence of partially purified IL-2RIF, these clones expressed IL-2R and showed IL-2-dependent proliferation, whereas they induced neither IL-2R expression nor proliferation in the absence of IL-2RIF activity. These observations suggest that IL-2RIF activity is mediated by a novel cytokine(s) and the cytokine plays an important role as a second signal in the activation of the TH1 clone.
Kato
T
T
Department of Allergology, University of Tokyo, Japan.
Inoue
T
T
Yamamoto
K
K
Tamura
T
T
Nariuchi
H
H
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D007375:Interleukin-1 / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000276:immunology; D008222:Lymphokines / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis*; D015290:Second Messenger Systems; D013601:T-Lymphocytes / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*
D007375:Interleukin-1; D015850:Interleukin-6; D008222:Lymphokines; D015375:Receptors, Interleukin-2