POSITIVE MODIFICATION OF EFFECTOR FUNCTIONS AND SUBSETS OF NEUTROPHILIC GRANULOCYTES CD64+CD32+CD16+CD11b+ AND CD64-CD32+CD16+CD11b+ UNDER THE INFLUENCE OF ARGINYL-α-ASPARTYL-LYSYL-VALYL-TYROSYL-ARGININE IN AN IN VITRO EXPERIMENT IN IMMUNOCOMPROMISED PATIENTS WITH IMMUNOSENESCENCE

Abstract

The increasing proportion of elderly and senile individuals in the human population determines the relevance of the problem of age-associated diseases, in the occurrence of which immunosenescence plays a key role. Neutrophil granulocytes (NG) are largely susceptible to this process, which requires studying changes in their functioning during immunosenescence and developing methods for experimental correction of NG dysfunctions.

Objective: to clarify the nature of NG dysfunctions during immunosenescence and to evaluate the effect of synthetic thymic hexapeptide (HP) on the effector functions and CD64⁺CD32⁺CD16⁺CD11b⁺ and CD64^-CD32⁺CD16⁺CD11b⁺ subsets of NG in elderly and senile individuals.

Materials and methods. The study involved 15 immunocompromised patients aged 60-78 years with COPD with prolonged and frequent exacerbations (SG1) and 30 conditionally healthy volunteers aged 60-74 years (CG): NG subsets (%) expression of CD64, CD32, CD16, CD11b receptors, the expression density of these receptors (MFI), phagocytic and microbicidal functions of NG in intact peripheral blood (SG1) and after incubation with GP (10^-6 g/l) for 60 minutes at T 37°C (SG1a).

Results. An increase in the content of CD64+CD32+CD16+CD11b+NG subset and a decrease in the content of the CD64-CD32+CD16+CD11b+ NG subset in SG1 in comparison to CG, an increase in the density of CD16 expression and a decrease in the density of CD11b expression on NG of both subsets were revealed. In addition, an impairment in the phagocytic and NADPH-oxidase activity of NG in SG1 is determined. Under the influence of HP, a large effect size of a decrease in the content of CD64⁺CD32⁺CD16⁺CD11b⁺ NG and an increase in the content of CD64^-CD32⁺CD16⁺CD11b⁺ NG, an increase in the MFI of CD11b on NG of both subsets, digestive activity, stimulated NADPH oxidase activity; the average effect size of a decrease in the MFI CD16 and an increase in actively phagocyting NG; low effect size in relation to the parameters characterizing the processes of absorption and spontaneous NADPH-oxidase activity of NG are noted.

Conclusion. Positive modification of NG functioning under the influence of GP was shown in an in vitro experiment in immunocompromised patients with immunosenescence.