Eosinophils are part of the granulocyte response in tuberculosis and promote host resistance in mice.

Host resistance to Mycobacterium tuberculosis (Mtb) infection requires the activities of multiple leukocyte subsets, yet the roles of the different innate effector cells during tuberculosis are incompletely understood. Here we uncover an unexpected association between eosinophils and Mtb infection. In humans, eosinophils are decreased in the blood but enriched in resected human tuberculosis lung lesions and autopsy granulomas. An influx of eosinophils is also evident in infected zebrafish, mice, and nonhuman primate granulomas, where they are functionally activated and degranulate. Importantly, using complementary genetic models of eosinophil deficiency, we demonstrate that in mice, eosinophils are required for optimal pulmonary bacterial control and host survival after Mtb infection. Collectively, our findings uncover an unexpected recruitment of eosinophils to the infected lung tissue and a protective role for these cells in the control of Mtb infection in mice.

Validating the surgical indication value of the LTB-S classification system for drug resistant tuberculosis.

BACKGROUND: Currently there is no guideline based on preoperative clinical parameters for assessing the prognosis of the adjunctive surgery for drug-resistant tuberculosis. METHODS: We retrospectively analyzed 138 patients who had undergone surgical resection as a treatment for drug- resistant tuberculosis after 24 months. Four clinical parameters on lesion type, treatment history, body physiological status, and surgery approach were evaluated. Categorical preoperative clinical parameters were analyzed by ordinal logistic regression model when considering postoperative complications as outcomes ordered in terms of severity. Statistically significant parameters were then combined in a single classification system for predicting the outcomes of the adjunctive surgery. FINDINGS: Diffused, progressive bilateral lesions, or active/progressive extra pulmonary tuberculosis (L3), and history of less than 2 months treatment before surgery (T3) were the strongest predicative parameters for postoperative complications and for surgery failure. Classification systems based on the four parameters were found to have a statistically significant effect on postoperative complications and postoperative efficacy. 24- month follow up indicated a high cure rate (above 95.5%) among patients without T3, L3, or severe physiological complications (B3). INTERPRETATION: A classification system based on objective clinical parameters showed predicative value for the prognosis of the adjunctive surgery and could guide management of drug-resistant Tuberculosis.