The effect of testosterone on cytokine production in the specific and non-specific immune response.

PROBLEM

Cytokine production of monocytes and lymphocytes differs between males and females. This difference is characterized by a decreased percentage of interleukin (IL)-2-producing lymphocytes and an increased percentage of IL-12, IL-1beta and tumour necrosis factor (TNF)-alpha-producing monocytes in males compared with females. In the present study, we investigated whether testosterone may explain these differences.

METHOD OF STUDY

Stimulated whole blood of healthy woman was incubated with different concentrations of testosterone. Intracellular lymphocyte production of IL-2 and interferon (IFN)-gamma, as well as intracellular monocyte production of IL-12, IL-1beta and TNF-alpha were measured using flow cytometry.

RESULTS

A significant increased percentage of IL-12- and IL-1beta-producing monocytes was found after incubation with physiological concentrations of testosterone. No effect of testosterone was found on IL-2- and IFN-gamma-producing lymphocytes and TNF-alpha-producing monocytes.

CONCLUSIONS

The increased percentage of IL-12- and IL-1beta-producing monocytes in males compared with females in vivo may be induced by testosterone, as the in vitro percentage of IL-12- and IL-1beta-producing monocytes is increased after incubation with physiological concentrations of testosterone.