Features of immunological reactivity in Sami women

Abstract

BACKGROUND: The Sami are a small group of indigenous people of the Russian Federation. The Sami have one of the lowest birth rates among all the peoples of the North of Russia. They often have more health problems than residents of other nationalities in the Murmansk region, due to a high incidence of acute respiratory infections. Extreme climatic and geographical conditions of the Arctic have a negative impact on immunological reactivity. AIM: To identify the features of immunological reactivity in Sami women. MATERIALS AND METHODS: Forty-nine practically healthy Sami women aged from 21 to 44 years living in the Lovozero Village in the Murmansk region were examined. A control group consisting of 50 practically healthy Russian women of the Arkhangelsk region of the same age range was used. The hemogram, phagocytic activity of neutrophils of peripheral venous blood, and the content of lymphocytes with CD3, CD4, CD8, and CD10 phenotypes were studied by indirect immunoperoxidase reaction (Sorbent, Moscow) and flow cytometry (Beckman Coulter Immunotech, France). Additionally, concentrations of IgM, IgG, IgA, sCD54, and sCD62L (Bender MedSystems, Austria) were determined by enzyme immunoassay, circulating immune complexes (CIC) were determined by the precipitation method. The total amount of microflora, cytogram, phagocytic activity of neutrophils, the sorption capacity of epithelial cells, the content of sIgA and CIC IgG were studied in the separated mucous membranes of the pharynx, intestines, and urine. For comparison between groups, the independent samples t-test or the nonparametric MannWhitney U-test was used depending on the distribution. RESULTS: In Sami women, the frequency of deficiency of phagocytic activity of blood neutrophils and mucosal secretions was higher than in the control group. Increased reactions of cell-mediated and antibody-dependent cytotoxicity of lymphocytes were recorded. The frequency of elevated concentrations of CIC was higher in the Sami women than in the control group. A remarkable feature of the Sami immune reactivity was high concentrations of IgA and IgM against a background of low IgG content. CONCLUSION: In Sami women, the percentage of actively phagocytic neutrophil granulocytes of peripheral venous blood and mucous membranes was lower than in the control. A distinctive feature of the immunoglobulin profile of the blood serum of Sami women was the low IgG content against the background of increased concentrations of CIC, including immunoglobulins of this class. Sami women had higher levels of leukocyte migration into mucosa-associated mucosal tissue, which was correlated with a decrease in the sorption capacity of epitheliocytes, phagocytic activity of neutrophils, and concentrations of secretory immunoglobulins.