The role ofMycobacterium tuberculosis complexspecies on apoptosis and necroptosis state of macrophages derived from active pulmonary tuberculosis patients

Objective The role ofMycobacterium tuberculosiscomplex (MTBC) species in tuberculosis (TB) infection in human is still questioned. The aim of this study was to determine whetherM. tuberculosisandM. bovisis associated with apoptosis and necroptosis by measuring the expression of specific signaling pathways components (Fas-associated protein with death domain (FADD) and receptor interacting protein 3 (RIP3)), and the level of apoptosis. Results We recruited 30 patients with pulmonary TB; 24 patients were infected withM. tuberculosisBeijing strain and six patients withM. bovisBCG strain.M. tuberculosis-infected patients were more likely to have severe lung damage compared to those infected withM. bovis (odds ratio [OR] 7.60; 95% confidence interval [CI] 1.07-54.09).M. tuberculosisinfection was associated with lower expression of FADD and lower apoptosis level of macrophages compared toM. bovis. No significant different of RIP3 between MTBC species groups. In conclusion,M. tuberculosisBeijing strain was associated with severe pulmonary damage, inhibited FADD expression and reduced apoptosis level of macrophages derived from pulmonary TB patients. This suggests that theM. tuberculosisBeijing strain is potentially to be used as determinant of disease progressivity and tissue damage in TB cases.