Changes of Lymphocyte Subsets in Pulmonary Tuberculosis

Background and Aims: The host immune system plays an important role in the pathogenesis and defense mechanism of Mycobacterium tuberculosis (M tb ). This study aimed to explore the changes of immune system in Pulmonary Tuberculosis (PTB) patients. Methods: A total of 85 active PTB patients and 50 healthy adults were enrolled, fifty patients with community-acquired pneumonia (CAP) were enrolled as the positive control. Chest CT and lymphocyte subgroup counts in peripheral blood were measured in all participants. Results: In the PTB group, the level of CD4 + and B cells and the ratio of CD4+/CD8 + cells were significantly increased, the frequency of NK cells was significantly decreased at the same time. Conclusions:  The manifestation of immune system was changed in PTB patients, the inflammation in the infected lesion was limited which decreased innate immune activation, and the increased of T and B cells responses as the main pathogen elimination method.