Activity of peripheral blood factors against <i>Candida albicans</i>

Abstract

Introduction. Currently, the colonization of various human biotopes by yeast-like fungi of the genus Candida is considered a relatively frequent phenomenon. At the same time, the clinical manifestations of the inflammatory process do not develop in every case, which implies the formation of a unique symbiosis between microscopic fungi and cells of the human body, the maintenance of which largely depends on the activity of the immune system. The main part of researches on the antifungal activity of the human immune system is concentrated around pathological conditions, and practically no attention is paid to such in healthy individuals. It has been shown that human immunity factors can, on the one hand, for example, contribute to the formation of C. albicans biofilms, and, on the other hand, take an active part in their destruction.The aim of the investigation was to evaluate the candidacid, antibiofilm, phagocytic and radical-producing activities of peripheral blood of healthy donors using C. albicans cells as an object.Materials and methods. Peripheral blood samples were obtained from 32 healthy donors, mycidal activity, absorption and radical-producing abilities of leukocytes, as well as the effect of blood serum on film biomass were assessed. For opsonization of C. albicans cells, immunoglobulins G were used according to the previously approved method.Results. A weak mycocidal activity of the peripheral blood of healthy donors was shown. Opsonization of C. albicans with immunoglobulin G significantly increases this blood function. In the early phase of contact with C. albicans, yeast-like cells mainly absorb by neutrophilic leukocytes, and mononuclear cells practically do not participate in the process of phagocytosis, probably their activity manifests itself in a later period. Opsonization of C. albicans stimulates the absorption activity of leukocytes, which is reflected in an increase in the average number of absorbed objects per leukocyte. It has been shown that opsonins can participate in enhancing the radical-producing activity of leukocytes. Thus, inactivation of proteins of the complement system levels the stimulating effect of C. albicans opsonization.Conclusion. Immunoglobulins G and proteins of the complement system make a significant contribution to the suppression of the pathogenic activity of C. albicans.