Gender differences in neutrophil function and cytokine-induced neutrophil chemoattractant generation in endotoxic rats

Several lines of evidence indicate sexual dimorphism in the immune response. We explored gender differences in phagocytosis by neutrophils (PMNs), CD11b/c expression, generation of cytokine-induced neutrophil chemoattractant (CINC) and the influence of developmental stages on some of these parameters. Phagocytosis by PMNs of reproductive female rats was not suppressed by anesthesia and surgery as it was in age-matched males. The phagocytic response to an endotoxin (ET) challenge was also higher in PMNs of reproductive females than in males or in prereproductive or postreproductive females. CINC generation in reproductive females was lower than in age-matched males. Phagocytosis in saline-treated postreproductive females was reduced compared to reproductive and prereproductive females, but was not different from adult males. CD11b/c expression was greater in PMNs of saline-treated postreproductive females, than in reproductive or prereproductive animals, but an ET challenge upregulated CD11b/c expression to the same level in all three groups. No gender difference was observed in this parameter. These data indicate that in terms of phagocytosis PMNs of reproductive female rats are more resistant to the effects of anesthesia and surgery and respond to an ET challenge more vigorously than cells of age-matched males. CINC generation in adult rats is also gender dependent. The developmental stages in females modulate phagocytosis and beta(2)-integrin expression in PMNs.