Immunosuppressive activity of Campylobacter jejuni isolates in relation to the cellular link of the body’s immunoprotection

Abstract

Global environmental changes have caused transformations in the biology of microorganisms, especially among campylobacter, which are currently associated with food toxic infections. The means of influence of these bacteria on susceptible organisms, namely toxins, have not been finally clarified. The purpose of this study was to investigate the genetic conditionality of toxin formation in isolates of Campylobacter jejuni and determination of the degree of inhibition of the body’s protective reactions by toxic fractions of Campylobacter protein compounds. The methodology of this study was based on the polymerase chain reaction using primers to indicate the nucleotide sequences of the Campylobacter jejuni genome that encode the synthesis of toxins. Samples from 4 Campylobacter isolates were examined for the content of protein fractions according to the Lowry assay. The analysis of the electropherogram of the results of DNA amplification in a comparative aspect with the data of standard samples allowed establishing the presence of genome elements that indicate the potential ability to produce toxins in Campylobacter jejuni isolates sampled from the material under study. Toxic fractions separated from the supernatant of Campylobacter jejuni broth culture are represented by protein-carbohydrate substances. The obtained peak toxigenic fractions of the dialysate of the bacterial culture sediment contained protein within 9.5-17 μg/ml. In the dialysate of the broth culture supernatant, where 5 groups of toxigenic fractions were distinguished, their protein content ranged within 10-85 μg/ml. By reproducing the opsono-phagocytic reaction involving toxigenic fractions of Campylobacter jejuni, a sufficiently pronounced immunosuppressive effect of these complexes on the body of warm-blooded animals was established with an opsonic index of 2.6 ± 0.03. The obtained results allow clarifying the connection between toxin formation in Campylobacter jejuni and their immunosuppressive effect on the body of warm-blooded animals and humans, which in the future will positively affect the improvement of measures for the prevention and treatment of animals with this pathology