Ab to the cryptococcal capsule protects in experimental infection remain unknown. The advent of mAb technology has allowed the generation of reagents which have been useful for dissection of the Ab response to this pathogen and for study of the effect of Ab on the host response to infection.
Macrophages remain prime suspects for the cells on which mAb acts.
Recently, however, attention has focused beyond the standard Ab functions of opsonophagocytosis resulting in enhanced killing toward exploration of areas such as enhancement of macrophage function in antigen presentation. Further, the complex nature of the development of granulomatous inflammation that allows containment of infection, and the apparent ability of Ab to the capsular polysaccharide to enhance this containment in murine infection has turned attention toward possible differences in cytokine milieu that may follow Ab administration. Though study of the effects of Ab on cytokines is likely to yield a heterogeneous body of information, with potential effects on a number of aspects of the immune response, differences in the setting of Ab administration will likely point to new mechanisms by which Ab exerts its effects. The study of Ab immunity in cryptococcal infection has produced observations that are unparalleled in Ab-mediated protection against other pathogens. The phenomena concerning IgG1 and IgG3 have not been described in microbial immunity for other pathogens.