Opportunities for immunocorrection aiming for reduction of morbidity in the areas with adverse occupational and environmental conditions

Previous studies have shown that prolonged professional contact with chemical xenobiotics contributes to sensitization of immune system and development of typical immunopathological processes, i.e., allergies and autoimmune diseases. Origin and severity of immune system disorders depends on the spectrum and duration of exposure to adverse factors and patterns of professional activity at the chemically hazardous facilities. The study of structural and functional changes in cellular, humoral and some factors of innate immunity in people working and living in areas with unfavorable environmental conditions revealed a number of immunological disorders that can be characterized as secondary immunodeficiency conditions, which may manifest with increased frequency of acute respiratory infections and other chronic diseases. Much attention is given to prevention and treatment of secondary immunodeficiency conditions, which are associated with decreased numbers of lymphocytes expressing CD3, CD4, CD8. The purpose of the study was determined by recent positive experience of using highly effective drugs based on thymic regulatory peptides affecting various steps of homeostasis, in order to correct immune disorders caused by exposure to radiation and other toxic substances. The aim of this study was to evaluate changes in immunity and effectiveness of immune correction by means of immunotropic drugs, i.e., Thymogen nasal spray, and Cytovir-3 capsules, in the cohorts living and working under the conditions of heavy chemical exposure. We observed 249 persons aged 18 years to 63 years recruited from the employees of the “Polygon “Krasny Bor” State Enterprise. The people had longterm professional contacts with the components of industrial toxic waste were under examination. Group 1 consisted of the administration staff, group 2 included drivers of special cargo transport. The control group consisted of 137 employees at the car enterprises in Saint Petersburg. The duration of follow-up observation was 1 year. The patients with a detected decrease in cellular immunity received immunotropic drugs based on alpha-glutamyl-tryptophan (Thymogen nasal spray dosed (Thymogen, 62 persons), or combined encapsuleted Cytovir-3 drug (Cytovir, 31 cases). 14 days after finishing the course, a second immunological study was conducted. Following the immunotropic therapies, the subjects showed an increase in relative content of CD3+, CD4+, and CD8+subpopulations, normalization of functional oxygen-dependent metabolism of polymorphonuclear neutrophil granulocyte system in the NBT test, as well as harmonization of the content of serum immunoglobulin contents. The one-year follow-up showed high effectiveness of these drugs, as shown by decreased incidence of acute infectious and lower exacerbation rates of chronic respiratory and gastrointestinal diseases. For the group 1 with working experience of 1 to 5 years, the persons who received Thymogen exhibited lower incidence of acute respiratory viral infections (a 37% decrease), like as less frequency of bronchopulmonary diseases (by 25% from the baseline). The patients with long-term work experience in an unfavorable area (Group 2), who received Thymogen, have shown four-fold reduction in acute respiratory morbidity, decreased frequency of other respiratory diseases (1.5-fold), and disorders of digestive organs (a 1.75-fold decrease). Among persons from the 1st and 2nd groups with work experience of up to 1 year, who received Cytovir-3, the SARS incidence decreased by 1.95 and 2.0 times, respectively. It is shown that timely detection of immune system disorders induced by the influence of complex harmful chemical factors, and administration of selective immunocorrecting therapy may contribute to reduction of acute and chronic morbidity in the people working under unfavorable environmental conditions.