Differences in the interleukin-2 (IL-2) receptor system in human and mouse: alpha chain is required for formation of the functional mouse IL-2 receptor.
Reconstitution with mouse interleukin-2 (IL-2) receptor subunits demonstrated that the mouse IL-2 receptor complex was different from the human complex in the alpha chain requirement for the functional mouse receptor complex. The heterotrimeric complex of the mouse exogenous alpha and beta chains and the endogenous gamma chain on mouse lymphoid BW5147 cells showed the ability to bind IL-2 with high affinity, resulting in IL-2-induced tyrosine phosphorylation of a cytosolic tyrosine kinase, JAK3, which is involved in IL-2-dependent signals. Exogenous introduction of the beta chain with the endogenous gamma chain, however, could neither confer appreciable IL-2 binding nor IL-2-induced signal transduction on BW5147 cells, unlike the human beta gamma heterodimer. Mouse spleen CD8+ cells, not having the alpha chain initially, showed IL-2-dependent cell proliferation only when expression of the alpha chain was induced. Collectively, these results illustrate that the functional mouse IL-2 receptor complex necessarily includes the alpha chain, and that the regulation of CD8+ T cell growth during immune reaction depends upon alpha chain expression.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002460:Cell Line; D005260:Female; D006801:Humans; D007376:Interleukin-2 / Q000378:metabolism; D053616:Janus Kinase 3; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D011505:Protein-Tyrosine Kinases / Q000276:immunology; D051381:Rats; D017208:Rats, Wistar; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis / Q000276:immunology* / Q000378:metabolism*; D014162:Transfection
D000911:Antibodies, Monoclonal; D007376:Interleukin-2; C507936:Jak3 protein, rat; D015375:Receptors, Interleukin-2; D011505:Protein-Tyrosine Kinases; C507933:JAK3 protein, human; C507935:Jak3 protein, mouse; D053616:Janus Kinase 3