[Anti-cytokine activity of microorganisms]

Development of a method of determination of anti-cytokine activity (ACA) of microorganisms, study of the prevalence and intensity of ACA to pro- and anti-inflammatory cytokines in pathogenic and opportunistic bacteria.

ACA was determined in 72 strains of microorganisms including members of the intestinal microflora and strains of pathogenic bacteria (salmonellae andgonococci). Study of the ability of supernatants and live cell cultures of microorganisms to induce changes in pro- (IFN-gamma, TNF-alpha, IL-6) and anti-inflammatory cytokines (IL-4, IL-10) was performed by using co-incubation of exometabolites and live cell bacteria, fungi with recombinant cytokines.

Amethodological approach allowing the determination of ACA, the prevalence of which among studied microorganisms was 50 - 62%, was developed. A decrease of cytokine concentration in the medium was registered in co-incubation of them with supernatants (in 56% of cases) and to a lesser degree--with live cell cultures (44%) of the studied bacteria and fungi. Expression ofanti-cytokine activity was the most pronounced to TNF-alpha (Bifidobacterium spp. and Lactobacillus spp., Neisseria gonorrhoeae), IFN-gamma (N. gonorrhoeae and Salmonella enterica) and IL-10 (Bifidobacterium spp. and Lactobacillus spp.).

The data obtained expand the conception of modification of cytokine dynamic by pathogenic and opportunistic microorganisms, that can influence the course and outcome of an infectious process.