Females in proestrus state maintain splenic immune functions and tolerate sepsis better than males.

OBJECTIVES

To determine: a) whether the cell-mediated immune response during sepsis differs in females vs. males; and b) whether the survival rate in females is different than in males after a septic insult.

DESIGN

A prospective, randomized animal study.

SETTING

University research laboratory.

SUBJECTS

Male and female proestrus C3H/HeN mice.

INTERVENTIONS

After anesthesia, male and proestrus female mice underwent cecal ligation puncture to induce sepsis. The mice were killed at 24 hrs after the onset of sepsis.

MEASUREMENTS AND MAIN RESULTS

Splenocyte proliferation, as well as splenocyte interleukin (IL)-2 and IL-3 release, was determined by bioassay. In additional studies, survival rate after septic challenge was measured over 10 days. Splenocyte proliferative capacity and splenocyte IL-2 and IL-3 release were markedly decreased in male, but not in female, septic mice. Furthermore, the survival rate of septic female proestrus mice was significantly higher than in comparable male mice.

CONCLUSIONS

These results support the concept that the immune response of females differs from males, and that females are immunologically better positioned to meet the challenge of sepsis.