INCREASED TISSUE RESISTANCE IN THE NUDE-MOUSE AGAINST CANDIDA-ALBICANS WITHOUT ALTERING STRAIN-DEPENDENT DIFFERENCES IN SUSCEPTIBILITY

Strain differences in tissue responses to infection with Candida albic ans were examined in nude mice having susceptible (CBA/CaH) and resist ant (BALB/c) parentage. Homozygous (nu/nu) mice of both strains were m ore resistant to systemic infection with C. albicans than heterozygous (nu/+) littermates as indicated by a reduction in both the severity o f tissue damage and colony counts in the brain and kidney. However, th e tissue lesions in nu/nu CBA/CaH mice were markedly more severe than those in nu/nu mice with the BALB/c background. This pattern was refle cted in the greater fungal burden in the CBA/CaH strain. Analysis of c DNA from infected tissues using a competitive polymerase chain reactio n excluded interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), and interleukin 6 (IL-6) as mediators of the enhanced res istance of the nude mice. The results confirm that the different patte rns of lesion severity in BALB/c and CBA/CaH mice do not involve T lym phocyte-mediated pathology, and are consistent with the hypothesis tha t strain-dependent tissue damage is not dependent on the effector func tion of macrophages or their precursors.