LAUSR

The study of natural antibodies as a function of maintaining immunological homeostasis from the position of physiological adaptation of a population is one of the goals of population physiology. The aim is to study natural AB0 antibodies across blood types among Moksha and Erzya ethic groups of the Republic of Mordovia. Methods. The cross-sectional study involved 294 and 387 people from Moksha and Erzya ethnic groups, respectively, randomly selected in 7 districts of Mordovia. The determination and activity of natural full AB0 anti-erythrocyte antibodies a (anti-A), р (anti-B) was carried out by titration. Results. The activity of natural antibodies of the first blood group in Moksha was from a-1: 8 р-1: 4, to a-1: 128 р-1: 64; in Erzya from a-1: 2 р-1: 2, to a-1: 256 р-1: 256. The titer of natural р-antibodies of the second blood group in Moksha and Erzya was not high. The most common titer was 1:8, 1:16, 1:32. The highest titers of natural antibodies in women were observed: in Moksha 1:64 and in Erzya 1:256. Normal a-antibodies of the B(III) group in Moksha and Erzia met with different titers, most often titer 1:8 was found as in Moksha men (45.45 %), and 1:16 in Erzya women - 43.55 %, in Erzya men - 40 %. An increased activity of antibodies was observed in women: 1:128 in Moksha - 13.46 %, 1:128 in Erzya - 14.32 % and 1:256 - 3.22 %. An increased antibody activity was also observed in Erzya men as 1:128 - 6.66 % and 1:64 - 20 %, in Moksha - 9.09 %. Conclusions. Physiological immune system in Moksha and Erzya actively responds with a production of natural, normal, group antibodies, which are of the great importance in studying of the physiological structure of population in specific environmental conditions.