title: Inhibition of protein tyrosine phosphatases prevents mesenteric lymph node T-cell suppression following alcohol intoxication and burn injury.
abstract: Previously, we have shown that acute alcohol (EtOH) intoxication before burn injury potentiates the suppression of mesenteric lymph node T-cell effector responses. Moreover, the suppression in T-cell was accompanied with a decrease in p-38 and extracellular-signal-regulated kinase (ERK) activation. This study examined the role of protein tyrosine phosphatases (PTP) in suppressed T-cell p-38, ERK, and cytokine production after EtOH intoxication and burn injury. A blood EtOH level of approximately 100 mg/dl in male rats (approximately 250 g) was achieved by gavaging animals with 5 ml of 20% EtOH suspension 4 hours before burn or sham injury (approximately 12.5% or 25% total body surface area [TBSA]). One day after injury, rats were killed and mesenteric lymph node T-cell cytokine (IL-2/IFN-gamma) production, p-38, and ERK activation were measured. As compared with shams, there was a significant decrease in T-cell cytokine production after 25% and not 12.5% TBSA burn injury. However, T-cell IL-2/IFN-gamma levels were significantly decreased in rats receiving a combined insult of EtOH and burn injury regardless of the percentage of burn area. Furthermore, we found a significant decrease in p-38 and ERK-1/2 phosphorylation in T-cells of rats receiving a combined insult of EtOH and 12.5% TBSA burn compared with shams. Treatment of cells with PTP inhibitor pervanadate (10 muM) prevented T-cell p-38/ERK suppression. The suppression in IL-2/IFN-gamma production was also attenuated in T-cells cultured in the presence of pervanadate. These findings suggest that an increase in PTP activity may contribute to T-cell suppression after EtOH intoxication and burn injury.
authors.affiliation: Center for Surgical Research and Department of Surgery, University of Alabama at Birmingham, Alabama 35294, USA.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Li
authors.forename: Martin G
authors.initials: MG
authors.lastname: Schwacha
authors.forename: Irshad H
authors.initials: IH
authors.lastname: Chaudry
authors.forename: Mashkoor A
authors.initials: MA
authors.lastname: Choudhry
mesh_terms: D000435:Alcoholic Intoxication / Q000150:complications* / Q000201:enzymology; D000818:Animals; D002056:Burns / Q000150:complications* / Q000201:enzymology; D016207:Cytokines / Q000187:drug effects / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007371:Interferon-gamma / Q000187:drug effects / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D008198:Lymph Nodes / Q000187:drug effects* / Q000473:pathology; D008297:Male; D023421:Models, Animal; D010766:Phosphorylation / Q000187:drug effects; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors*; D051381:Rats; D013491:Suppressor Factors, Immunologic; D013601:T-Lymphocytes / Q000473:pathology*; D014638:Vanadates / Q000494:pharmacology*
chemical_list: D016207:Cytokines; D004791:Enzyme Inhibitors; D007376:Interleukin-2; D013491:Suppressor Factors, Immunologic; C076715:pervanadate; D014638:Vanadates; D007371:Interferon-gamma; D017027:Protein Tyrosine Phosphatases