Drug-Tolerant Adopt Different Survival Strategies in Alveolar Macrophages of Patients with Pulmonary Tuberculosis.

The rapid spread of drug-resistant () strains and the phenomenon of phenotypic tolerance to drugs present challenges toward achieving the goal of tuberculosis (TB) elimination worldwide. By using the ex vivo cultures of alveolar macrophages obtained from lung tissues of TB patients after intensive antimicrobial chemotherapy before surgery, different subpopulations of multidrug-tolerant with a spectrum of phenotypic and growth features were identified in the same TB lesions. Our results are indicative of not only passive mechanisms generating nonheritable resistance of to antibiotics, which are associated mainly with a lack of growth, but also some active mechanisms of persistence, such as cell wall and metabolic pathway remodeling. In one of the subpopulations, non-acid-fast have undergone significant reprogramming with the restoration of acid-fastness, lipoarabinomannan expression and replication in host cells of some patients after withdrawal of anti-TB drugs. Our data indicate the universal stress protein Rv2623 as a clinically relevant biomarker of that has lost acid-fastness in human lungs. The studies of survival, persistence, dormancy, and resumption and the identification of biomarkers characterizing these phenomena are very important concerning the development of vaccines and drug regimens with individualized management of patients for overcoming the resistance/tolerance crisis in anti-TB therapy.