IL-4 inhibits human CD8 T cell expression of the common IL-2 receptor gamma chain.
Previous studies in both rats and humans have shown that interleukin (IL) 4 can suppress the generation of IL-2-producing CD8 T cells. In an attempt to elucidate the mechanism by which this suppression is brought about, we set out to investigate whether the IL-4 signal interferes with the IL-2 receptor system. It has already been reported that IL-2 can affect the expression of its own receptor and thus provide a means of controlling its own activities. In this study, we demonstrate that the IL-2 Ralpha- and the IL-2 Rgamma-chains are dramatically upregulated following stimulation of CD8 T cells, whereas lower levels of beta-chain are observed. IL-4 did not affect the expression of the alpha- or beta-chains, but was found to inhibit the generation of common gamma-chain-expressing cells. Moreover, CD4 T cells were found to express much lower levels of this subunit and appeared less sensitive to the effects of IL-4. We postulate that the differential expression of the gamma-chain subunit, in the presence and absence of IL-4, may provide a tool for identifying functionally distinct subpopulations of CD8 T cells.
Vyas
B
B
Department of Immunology, Guy's, King's, and St. Thomas's School of Medicine, Rayne Institute, London, UK.
Vukmanovic-Stejic
M
M
Noble
A
A
Kemeny
D M
DM
D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005434:Flow Cytometry; D006801:Humans; D007142:Immunoglobulin gamma-Chains / Q000276:immunology; D015847:Interleukin-4 / Q000276:immunology* / Q000494:pharmacology; D051381:Rats; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis / Q000276:immunology*; D015398:Signal Transduction / Q000276:immunology
D007142:Immunoglobulin gamma-Chains; D015375:Receptors, Interleukin-2; D015847:Interleukin-4