Both CD4(+) and CD8(+) lymphocytes reduce the severity of tissue lesions in murine systemic candidiasis, and CD4(+) cells also demonstrate strain-specific immunopathological effects

The role of T lymphocytes in host responses to sublethal systemic infection with Candida albicans was evaluated by mAb depletion of CD4(+) and CD8(+) cells from BALB/c and CBA/CaH mice, which develop mild and severe tissue da mage, respectively. Depletion of CD4(+) lymphocytes from BALB/c mice marked ly increased tissue damage, but did not alter the course of infection. In C BA/CaH mice, depletion of CD4+ cells abrogated tissue destruction in both b rain and kidney at day 4 after infection, and significantly decreased funga l colonization in the brain. However, the severity of tissue lesions increa sed relative to controls from day 8 onwards. A small increase in tissue dam age was evident in both mouse strains after depletion of CD8(+) cells. Ther e were no major differences between days 4 end 8 after infection in cDNA cy tokine profiles of CD4(+) lymphocytes from either BALB/c or CBA/CaH mice. A fter passive transfer into infected syngeneic recipients, spleen cells from infected CBA/CaH mice markedly increased tissue damage when compared to co ntrols, and also caused a significant increase in fungal colonization in th e brain. A similar transfer in BALB/c mice increased the number of inflamma tory cells in and around the lesions, but had no effect on the fungal burde n in brain and kidney. The data demonstrate that both CD4(+) and CD8(+) lym phocytes contribute to the reduction of tissue damage after systemic infect ion with C. albicans, and that the development and expression of CD4(+) lym phocyte effector function is influenced by the genetic background of the mo use.