Hormonal modulation of sex differences in resistance to Leishmania major systemic infections

Abstract

Differences in susceptibility to intravenously inoculated Leishmania major were observed in male and female mice of the BALB/cAnPt, DBA/2N, and DBA/2J strains and (BALB/cAnPt x DBA/2N)F1 hybrids. In all cases, males had significantly higher liver parasite burdens than females. Orchidectomy of BALB/c males resulted in a 20% decrease in the number of parasites in the liver compared with either normal or sham-gonadectomized controls. Additionally, testosterone treatment of female BALB/c mice resulted in an 88% increase in the number of liver amastigotes. These results suggest that the hormone testosterone can modulate systemic L. major infections in BALB/c mice.