CELL DEATH MODES OF WHITE BLOOD CELLS IN PATIENTS WITH COMMUNITY-ACQUIRED PNEUMONIA AND PULMONARY TUBERCULOSIS

<b>Aim:</b> To assess the modes of cell death of white blood cells (WBCs) in patients with community-acquired pneumonia (CAP) and pulmonary tuberculosis (PTB). <b>Materials and methods:</b> Flow cytometry analysis (FCA) was performed in 12 patients with CAP, 30 patients with PTB and 22 volunteers. FCA using FITC-labeled annexin V (AV), anti-CD45 PE and 7-aminoactinomycin D (7-AAD) markers was performed to evaluate the amount of viable, early apoptotic, late apoptotic/necrotic, and dead necrotic circulating WBCs on a flow cytometer. <b>Results:</b> The amount of AV-negative, 7-AAD-negative viable WBCs was found to be lower in PTB (p&lt;0.05). The percentage of such WBC in PTB was 71.1 %, whereas in CAP was 94.8 % and in the control subjects - 97.0 %. Considering modes of WBC cell death, we revealed that the percentage of AV-positive, 7-AAD-negative cells was significantly (p&lt;0.05) higher in patients with PTB compared with CAP and controls (14,7 % against 1.5 % and 1.0 %, respectively). The percentage of AV-positive, 7-AAD-positive WBCs was found to be statistically significantly (p&lt;0.05) higher in PTB, reaching 12.3 % in comparison with 1.1 % in CAP and 0.7 % in the control group, which is indicative of an increase in the number of late apoptotic/necrotic WBCs. The percentage of dead necrotic cells (AV-negative,7-AAD WBCs) was statistically significantly (p&lt;0.05) higher in CAP compared with PTB and volunteers. Numerical values reached 2.6 % in CAP against 0.9 % in PTB and 1.3% in controls. <b>Conclusions:</b> PTB is accompanied by a higher rate of leukocyte apoptosis, but a lower percantage of circulating dead necrotic WBCs, in comparison with CAP, which may be assosiated with chronic inflammatory effects.