Flow cytometric measurement of rat lymphocyte subpopulations after burn injury and burn injury with infection.
Increased infection rates in burned patients may result from a disproportionate increase in the suppressor subpopulations. Measurement of lymphocyte subpopulations is difficult in burned patients because gradient-purified cells are contaminated by nonlymphoid cells. The accuracy of flow cytometric subpopulation analysis was improved by restricting (gating) the analysis to cells with light-scatter intensity typical of lymphocytes. Blood was obtained 48 hours after burn from rats receiving no burns, 30% scald burns, or burns seeded with Pseudomonas aeruginosa to induce infection. Subpopulations were identified by monoclonal antibodies to T-lymphocyte antigens. Gating increased the values obtained for most subpopulations, but the relative differences between groups were unchanged. Burned and infected animals, but not animals burned only, had a decreased ratio of helper to suppressor lymphocytes (HSR) relative to control. A decreased HSR correlated with sepsis, but not with infection susceptibility. This suggests that a decrease in HSR may be a result of infection rather than a cause of susceptibility to infection.
D000818:Animals; D001799:Blood Sedimentation / Q000379:methods; D002056:Burns / Q000473:pathology*; D002469:Cell Separation / Q000379:methods; D005434:Flow Cytometry / Q000379:methods; D008214:Lymphocytes / Q000473:pathology*; D051381:Rats; D012377:Rodentia