RESUMO
It is well fnown that an immunosuppresive rsponse occuts after acute trauma. Some cellular mediators participate in the pathogenesis of septic shock. However, the exact role of the lymphocyte subsets and natural killer (NK) activity in this condition is not clear. We studied NK cytolytic activity through a 51Cr liberation assay using K-562 target cells in 20 patients with initial septic shock (10 men and 10 females, mean age 41 years old). Lymphocyte subsets CD3 (T3), CD4 (T4), CD8 (T8), CD16 (Leu-11) and CD56 (Leu-19) wetre also studied by indirect immunofluorescence. Compared to tesults obtained in 20 healthy volunteers, patient's NK activity was decreased (4.6 ñ 3.9 vs 26.1 ñ 10, p < 0.025), CD16 was lower (10%/187 vs 15%/280 per ul) and CD56 was also lower (6%/120 vs 12%/224 per ul), p < 0,05. T lymphocyte subsers were also decreased: CD3 cells (1100 vs 1352 per ul) and CD4 cells (634 vs 873 per ul), p < 0.05. Thus, a severe decrease in NK cells and NK cell function as well as decreases in CD3 and CD4 lymphocyte subsets are present in the initial stages of septic shock. The predictive value of these findings is currently under study