title: T-lymphocyte Ca2+ signalling and proliferative responses during sepsis.
abstract: Alterations in T-lymphocyte kinetics and/or activation have been implicated in burn and traumatic injury. This study evaluated concanavalin A (Con A) regulation of both intracellular Ca2+ (Cai2+) and proliferation in T-lymphocytes harvested from spleens of septic rats. Rats were implanted with fecal pellets containing Escherichia coli (150 colony forming units (CFU)) and Bacteroides fragilis (10(4) CFU). T-cell[Ca2+]i was measured before and after treatment of cells with ConA, using Fura-2 and microfluorophotometry. Splenic lymphocytes were cultured for 72 h with Con A to assess their proliferative response. As compared to sterile-implanted rats, the septic rat T-lymphocytes Cai2+ response to Con A significantly decreased on days 1 and 2 after implantation. A significant decrease in T-cell proliferative response to Con A, compared to sterile controls, was found in septic rats on day 2 but not on day 1. These results suggest that Con A-mediated proliferation in T-cells occurs secondarily to a decrease in cellular Ca2+ signalling. The depression in the T-cell proliferative response during sepsis could contribute to a decrease in host's resistance against sepsis.
authors.affiliation: Department of Physiology, Loyola University of Chicago, Stritch School of Medicine, Maywood 60153, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Choudhry
authors.forename: S
authors.initials: S
authors.lastname: Ahmad
authors.forename: K D
authors.initials: KD
authors.lastname: Thompson
authors.forename: M M
authors.initials: MM
authors.lastname: Sayeed
mesh_terms: D000818:Animals; D001442:Bacteroides Infections / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D001441:Bacteroides fragilis; D002118:Calcium / Q000378:metabolism*; D003208:Concanavalin A / Q000494:pharmacology; D004195:Disease Models, Animal; D004927:Escherichia coli Infections / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D066298:In Vitro Techniques; D007700:Kinetics; D008213:Lymphocyte Activation; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D018805:Sepsis / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D015398:Signal Transduction; D013154:Spleen / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology
chemical_list: D003208:Concanavalin A; D002118:Calcium