**Abstract**

Neutrophilic granulocytes (NGs) are very important cells of innate immunity that can very quickly realize antibacterial and antiviral defense. Until the present time, the phenomenon of different levels of presentations of membrane receptors CD16 and CD11b NG in normal and pathological conditions wasn't studied. We had studied the population of CD16+ CD11b+ NG in two groups of patients with acute viral and acute bacterial infections in the models of acute bacterial tonsillitis (ABT) and acute viral tonsillitis-EBV infection (AEBVI), having the same clinical symptoms in early stages of the disease. Comparative analysis of the redistribution of equipment intensity of CD16 and CD11b has detected three subpopulations of CD16+ CD11b+ NG population—CD16brightCD11bbright, CD16brightCD11bdim, and CD16dimCD11bbright—in normal and pathological conditions. It was found that subpopulation CD16brightCD11bdimNG dominates in healthy individuals; subpopulation CD16brightCD11bbrightNG dominates in patients with acute viral infection; subpopulation CD16dimCD11bbrightNG dominates in patients with acute bacterial infections. We had demonstrated that the study of CD16<sup>+</sup> CD11b+ NG subpopulations allows in early stage of diseases to diagnose acute viral and acute bacterial infections. Our studies have demonstrated the positive effects of eukaryotic DNA sodium salt on the negatively altered phenotype subpopulation CD16+ CD11b+ NG, in particular, through the remodeling of the expression of CD11b on NG membrane.

**Keywords:** neutrophilic granulocytes, subset, phenotype, receptors, acute viral and bacterial infections, eukaryotic DNA sodium salt

### **1. Introduction**

Neutrophil granulocytes (NGs) are the most mobile and numerous populations of innate immunity cell, which reacts lightly to any aggression, which also carries out powerful anti-infectious protection.

The surprising universality and multifunctionality of this cell, once again, underline the existence of heterogeneity within the NG population, that is,

the presence of subpopulations with different immunological roles. The use of monoclonal antibodies made it possible to confirm the existence of NG subpopulations using phenotypic characteristics. In 1998, the first nomenclature of human neutrophils antigens (HNAs) was created on the basis of membrane-expressed glycoprotein groups: HNA-1 (FcγRIIIb, CD16), HNA-2 (CD177), HNA-3 (CTL2), HNA-4 (CD11b/CD18, Mac-1, CR3), and HNA-5 (CD11a/CD18) [1]. The concept of heterogeneity of NG was discussed by scientists for more than 20 years and was confirmed with the accumulation of evidence on the presence of subsets of NG with various functions both in healthy subjects and in various diseases. Various methods have been used to detect the subpopulations of NG, such as cell maturity, functional activity, and localization, including receptors or markers of the cell surface.
