Inhibition of T cell MAPKs (Erk 1/2, p38) with thermal injury is related to down-regulation of Ca2+ signaling.
We evaluated MAPK (Erk 1/2 and p38) signaling mechanisms of altered T-cell-mediated immune responses in thermal injury condition. Rats were subjected to 30% body surface scald burn, and their mesenteric lymph node (MLN) and Peyer's patch (PP) T cells were purified using nylon wool method. Activation of MAPKs, Erk 1/2 and p38 was assessed in T cells by determining its phosphorylation using immunoblot analysis, intracellular immunostaining and confocal microscopy. The results showed a down-regulation of Erk 1/2 and p38 activation in anti-CD3-stimulated T cells from thermally injured animals, compared to Erk 1/2 and p38 in sham rat T cells. The down-regulation of MAPKs in T cells was reversed by treatment of T cells with calcium agonist, ionomycin. These data indicate that attenuated MAPKs (Erk 1/2, p38) activation in thermally injured animals' T cells could result from derangement of Ca(2+) mobilization. This finding suggests that T cell signaling derangements with thermal injury involve an altered cross-talk between Ca(2+) mobilization and MAPK signaling mechanisms.
Fazal
Nadeem
N
Burn and Shock Trauma Institute, Department of Surgery, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA. nfazal@lumc.edu
Choudhry
Mashkoor A
MA
Sayeed
Mohammed M
MM
D000818:Animals; D002056:Burns / Q000276:immunology*; D002118:Calcium / Q000819:agonists / Q000378:metabolism; D020013:Calcium Signaling; D015536:Down-Regulation; D004789:Enzyme Activation; D015759:Ionomycin / Q000494:pharmacology; D008198:Lymph Nodes / Q000166:cytology; D008213:Lymphocyte Activation; D008297:Male; D008643:Mesentery; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors*; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors*; D010581:Peyer's Patches / Q000166:cytology; D010766:Phosphorylation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013601:T-Lymphocytes / Q000201:enzymology*; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors*
D015759:Ionomycin; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D048051:p38 Mitogen-Activated Protein Kinases; D002118:Calcium