IMMUNOHISTOCHEMICAL EVALUATION OF SURFACTANT-ASSOCIATED PROTEINS SP-B AND SP-C AT FIBRO-CAVERNOUS PULMONARY TUBERCULOSIS
Tuberculosis remains one of the most pressing medical and socioeconomic problems. Currently, about a third of the world's population is infected with Mycobacterium tuberculosis. Among the causes of death from infectious diseases, tuberculosis is more than 80%.Surfactant is known to have a special place in the local lung protection system. Surfactant proteins play the most important role in the regulation of phospholipid metabolism, in the organization of the structure of surfactant membranes, in immunity reactions. In this regard, the purpose of our study was to study the state of surfactant proteins in the foci of specific destruction and in the surrounding intact lung tissue to assess its functional state, the degree of respiratory failure and possible dissemination of tuberculous inflammation.The material for the study was fragments of the lungs of the dead or operated on for cavernous pulmonary tuberculosis (n =163) with active bacteria excretion (n = 89) and with clinical abacillation (n = 74).It was established that in all the studied samples, both in the areas of cavernous destruction and pericavernosal zone, and in the intact lung tissue, dynamic depression of surfactant-associated proteins B and C was detected. The maximum expression of immunohistochemical expression was recorded in the alveolar macrophages, which indicated intensive recycling and utilization of the components of the surfactant. In intact lung tissue, the amount of SP-C was significantly reduced. At the same time, in the focus of the cavernous destruction and the pericavernous zone, this apoprotein totally disappeared. Thus, a decrease in the production of surfactant components leads to disorganization of the alveoli with their subsequent collapse and the development of respiratory failure.