Proliferative activity of stromal cell elements at fibrous-cavernous pulmonary tuberculosis depending on macrophageal immunophenotype

Aim of this study was to evaluate the proliferative activity of stromal cellular elements at fibrous-cavernous pulmonary tuberculosis depending on macrophageal immunophenotype.
Biopsy samples from patients with fibrous-cavernous tuberculosis divided into group with active bacillation (n=52) and with clinical abacillation (n=31) were studied. To evaluate the immunophenotype of the macrophageal pool the immunohistochemical study was performed using CD68 and VEGF-A markers. The proliferative activity of pulmonary stroma cellular elements was evaluated using Ki-67 marker.
The performed immunohistochemical evaluation has revealed the presence of two immunophenotypes of macrophages: VEGF-A+ and VEGF-A-, characterized by various localization and quantitative characteristics depending on bacillation activity. Active bacillation was accompanied with predominance of highly active CD68+/VEGF-A-
macrophages (M1), intensification of exudative reactions and phagocytosis, as well as formation of perifocal areas of serous / caseous pneumonia, while the clinical abacillation group was characterized by the increased number of CD68+/VEGF-A+ cells without signs of proliferative activity and stabilization of alterative and exudative processes.
Thus, in fibrous-cavernous tuberculosis it is present two immunophenotypically different subpopulations of macrophages CD68+/VEGF- and CD68+/VEGF+ with an inductive effect on the severity of immunological reactions, as well as remodeling of the pulmonary parenchyma in the form of pathological angiogenesis and pneumofibrosis are recorded.
As the severity of alterative-exudative processes increases and/or the proximity to the site of specific inflammation, an increase in the pool of VEGF- macrophages characterized by high and moderate phagocytosis activity is noted.