Plasticity of IL-2 and IL-2 receptor chains in rat lymphoid tissues in situ after stimulation with staphylococcal enterotoxin A.
Although the effects of mitogens on the synthesis of interleukin-2 (IL-2) and IL-2 receptor (IL-2r) have been described, a detailed in situ analysis of the spatio-temporal changes of the expression of the IL-2 gene and the three IL-2r components in lymphoid tissues is still missing. Therefore, we analyzed the IL-2 and IL-2r expression after a staphylococcal enterotoxin A (SEA)-induced T cell activation on a cellular and anatomical basis in the Wistar rat. SEA caused a rapid induction of IL-2 mRNA in T cells of spleen, lymph node, and thymus, followed by the appearance of high systemic IL-2 serum levels (5 ng/ml), and a significant increase of CD25 on CD4+ and CD8+ lymphocytes. The histotopographic analysis of the IL-2r chains revealed a strong upregulation of IL-2r alpha (alpha) and IL-2r beta (beta) mRNAs in similar T cell specific compartments of spleen, lymph node, and thymus as seen for IL-2 mRNA. The abundant constitutive expression of IL-2r gamma (gamma) mRNA was unaffected by SEA. The parallel upregulation of IL-2, IL-2ralpha, and beta chains in conjunction with the continuous presence of the IL-2rgamma chain predominantly in T cell regions of immune organs suggests that the biological effects of IL-2 are essentially limited to T cells, at least after superantigen stimulation.
Bette
Michael
M
Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps University, Robert-Koch Street 8, Marburg 35033, Germany. bette@mailer.uni-marburg.de
Geisler
Tobias
T
Fairless
Richard
R
Romeo
Horacio
H
Schäfer
Martin K-H
MK
Weihe
Eberhard
E
D000818:Animals; D001345:Autoradiography; D004768:Enterotoxins / Q000494:pharmacology*; D005786:Gene Expression Regulation; D007369:Interferon Inducers / Q000494:pharmacology*; D007376:Interleukin-2 / Q000378:metabolism*; D008221:Lymphoid Tissue / Q000187:drug effects*; D051379:Mice; D012333:RNA, Messenger / Q000187:drug effects; D051381:Rats; D015375:Receptors, Interleukin-2 / Q000187:drug effects*; D013154:Spleen / Q000187:drug effects; D013601:T-Lymphocytes / Q000187:drug effects
D004768:Enterotoxins; D007369:Interferon Inducers; D007376:Interleukin-2; D012333:RNA, Messenger; D015375:Receptors, Interleukin-2; C026066:enterotoxin A, Staphylococcal