To improve present results with antifungal drugs, modulation of the host im
mune response is being explored. Human phagocytes of various lineages work
cooperatively in vitro with antifungal drugs to inhibit or kill fungal path
ogens, and this activity is augmented by several recombinant cytokines. Mon
oclonal antibodies against the cryptococcal capsule have been shown to act
as an adjunct in enhancing the outcome of cryptococcosis in animal models.
This approach is now being pursued in systematic clinical trials. In experi
mental candidiasis, several manipulations of the immune system, via adminis
tration of cytokines, gene deletion or antibodies to cytokines, have been s
hown to significantly affect survival and fungal clearance in vivo. This ap
proach has already been demonstrated to be of benefit with recombinant huma
n granulocyte-colony stimulating factor adjunct therapy of human candidiasi
s. Combining antifungal drugs of different classes may enhance their therap
eutic effect.