State of immune homeostasis in hydrographers at the Northern Fleet of Russian Federation, considering their work experience

Labor activity, terms of exposure to professional factors and work experience contribute to modulation of both physiological and psychological functions of the human body. Ecological and climatic features of high latitudes, characterized by almost year-round low temperatures, reduced UV insolation and altered photoperiodism lead to adverse impact of professional activity. The complex of professional and environmental factors is stressful for adaptive abilities, including immune system. The aim of our study was to assess the influence of work experience on the state of immune homeostasis in hydrographers at the Northern Fleet of Russian Federation. A total of 64 practically healthy men working under the conditions of Northern seas were examined, depending on the length of their service: (1) work experience of 2.3±0.4 years; (2) 9.0±0.5 years; (3) 15.9±0.6 years; (4) 28.9±1.0 years. The number of lymphocytes (CD5⁺, CD10⁺, CD95⁺, CD71⁺) and the ratio of their contents (CD10⁺/CD95⁺ and CD71⁺/CD95⁺) were determined in peripheral blood using the indirect immunoperoxidase reaction technique with monoclonal antibodies on dried-drop lymphocyte preparations with a peroxidase conjugate stained with a chromogenic solution. The data analysis showed that the number of CD5⁺ lymphocytes decreases in individuals with up to 9.0±0.5 years of work experience. The ratios of the cell contents CD10⁺/CD95⁺, and CD71⁺/CD95⁺ varied from 0.94 to 1.06, being within optimal reference values 1±0.05, without any statistically significant difference depending on the length of service. It was found that the suggested mechanisms of immune adaptation proceeds in two ways: in young hydrographers with short and intermediate working experience it is implemented via maintenance of lymphoproliferation-to-apoptosis ratio, due to CD10⁺/CD95⁺, along with decreased levels of CD5 marker expression. In older hydrographers with significant and long-term work experience, it proceeds via restoration of CD5 marker expression, along with expanded distribution range of CD10/CD95 ratio and maintenance of CD71⁺/CD95⁺ ratio within strict limits. The obtained results suggest a need for individual medical and biological monitoring in order to correct the immune homeostasis of the people working in high latitudes.