Contribution of granulocytes and monocytes to resistance against experimental disseminated Candida albicans infection

Abstract

The aim of the present study was to investigate the contribution of granulocytes and monocytes to resistance against an acute systemic candidal infection in mice. To this end granulocytopenia and monocytopenia were induced by irradiation or treatment with cyclophosphamide, and monocytopenia was obtained by treatment with VP-16. After intravenous injection of 1 X 10(4) Candida albicans into mice irradiated with 8 GY, the number of Candida albicans cultured from the kidneys, expressed as the geometric mean of the number of CFU/g tissue, was 5.4 X 10(4), 7.1 X 10(6) and 5.8 X 10(7) on days 1, 3 and 5 of infection respectively (p less than 0.001 compared to normal mice). The number of Candida albicans cultured from the liver and spleen was also significantly higher for irradiated animals than for normal mice (p less than 0.001). For cyclophosphamide-treated mice the number of organisms in the kidney (1.7 X 10(4) CFU/g on day 1, 1.9 X 10(6) on day 3 and 3.8 X 10(6) on day 5 of infection) and spleen was significantly higher (p at least less than 0.02) than for normal mice after injection of 1 X 10(3) Candida albicans. Monocytopenia induced by VP-16 did not result in an increase in the number of Candida albicans cultured from the kidney or spleen after infection. From these studies it is concluded that granulocytes and not monocytes or exudate macrophages play an important role in resistance against Candida albicans during the first five days of a systemic infection.