Functional activity of neutrophils in guinea pigs, immunized with conjugates, based on BCG antigens with betulin and its derivatives

The aim of research was to study the activity of oxygen-independent and oxygen-dependent bactericidal systems of neutrophils in animals infected with Mycobacterium bovis against the background of preliminary sensitization of the body with conjugates based on BCG antigens with adjuvants of plant origin. An experiment was carried out on 55 guinea pigs, divided into 11 groups of 5 heads each. Individuals of groups 1-3 were injected subcutaneously with the BCG antigenic complex conjugated with betulin, respectively, in doses of 0.5; 1.0 and 1.5 mg/ml protein; groups 4-6 - preparation with betulinic acid according to a similar scheme, a drug with betulinic acid and groups 7-9 - a conjugate with betulonic acid in the same doses; the 10th group consisted of animals vaccinated with BCG vaccine intradermally at a dose of 0.1 mg, and the 11th group - intact guinea pigs (control). As a result of the study, it was found that with an increase in the concentration of corpuscular adjuvants in the experimental conjugate, the activity of oxygen-independent (lysosomal cationic proteins) and oxygen-dependent (myeloperoxidase) bactericidal systems of leukocytes decreases. The most pronounced increase in the content of cationic proteins and myeloperoxidase on the 30th day after the introduction of a virulent culture of mycobacteria (in addition to animals vaccinated with BCG) was observed in guinea pigs immunized with preparations containing betulinic acid at doses of 1.0 and 0.5 mg/ml. In individuals of the same experimental groups, the lowest degree of damage to the internal organs was recorded during the pathological and anatomical examination. The results obtained indicate that the use of betulin derivatives as adjuvants for vaccine preparations is promising.