Sex differences and cross-immunity in DBA/2 mice infected with L. mexicana and L. major.
Female DBA/2 mice were found to be highly resistant to Leishmania mexicana and rarely developed lesions even when inoculated subcutaneously with high numbers (5 x 10(6] of amastigotes. Male DBA/2 mice, on the other hand, were much more susceptible to this parasite and often developed non-healing lesions even when inoculated subcutaneously with comparatively few (5 X 10(4] amastigotes. Conversely, although both male and female DBA/2 mice developed ulcerating lesions when inoculated subcutaneously with L. major amastigotes, lesions invariably healed in males but did not heal in females. Male DBA/2 mice recovered from L. major infection subsequently were found to be resistant to subcutaneous challenge with L. mexicana. Conversely female DBA/2 mice that had failed to develop lesions when infected with L. mexicana developed lesions which healed following subcutaneous challenge with L. major. Thus there is bilateral cross-immunity between L. mexicana and L. major in DBA/2 mice which overrides differences in sex-determined susceptibility to both organisms.
Alexander
J
J
University of Strathclyde, Immunology Division, Todd Centre, Glasgow.
D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D007894:Leishmania mexicana / Q000254:growth & development / Q000276:immunology; D007895:Leishmania tropica / Q000254:growth & development / Q000276:immunology; D007896:Leishmaniasis / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C / Q000276:immunology / Q000469:parasitology*; D008811:Mice, Inbred DBA / Q000276:immunology / Q000469:parasitology*; D012737:Sex Factors