Altered T cell cytokine production following mechanical trauma.
BACKGROUND
Cell mediated immunity is suppressed following traumatic injury. The Objective is to determine whether there is a shift from T helper type 1 (TH1) to TH2 cell cytokine production following mechanical trauma in a rat model.


METHODS
Male Sprague-Dawley rats were anesthetized and subjected to bilateral femur fractures or sham injury. Spleens were removed 3 days later. T cell proliferation and cytokine production were stimulated by culturing spleen cells with the T cell mitogen concanavalin A (con A). Interleukin-2 (IL-2), interferon-gamma (IFN-gamma), IL-10 and IL-4 concentrations were measured in spleen cell supernatants using enzyme linked immunosorbent assays.


RESULTS
Con A-induced spleen cell proliferation was decreased in traumatized rats compared to controls (p < 0.05). Spleen cell supernatant concentrations of the TH1 cytokines IL-2 and IFN-gamma were decreased in the trauma group (p < 0.05). Supernatant concentrations of the TH2 cytokine IL-10 were also decreased in traumatized rats (p < 0.01). The IL-4 concentrations were below the detection limit (< 15 pg/mL) in all cell supernatants.


CONCLUSIONS
Mechanical tissue injury leads to generalized suppression of T helper cell cytokine production rather than a shift from TH1 to TH2 cell activity. Post-trauma cellular immunosuppression is not mediated via excess IL-10 production by TH2 cells.
Meert
K L
KL
Department of Pediatrics, Children's Hospital of Michigan, Wayne State University School of Medicine, Detroit 48201, USA.
Ofenstein
J P
JP
Sarnaik
A P
AP
D000818:Animals; D016207:Cytokines / Q000096:biosynthesis*; D005264:Femoral Fractures / Q000276:immunology; D007371:Interferon-gamma / Q000032:analysis; D016753:Interleukin-10 / Q000032:analysis; D007376:Interleukin-2 / Q000032:analysis; D015847:Interleukin-4 / Q000032:analysis; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013154:Spleen / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014947:Wounds and Injuries / Q000276:immunology*
D016207:Cytokines; D007376:Interleukin-2; D016753:Interleukin-10; D015847:Interleukin-4; D007371:Interferon-gamma