NCR negative group 3 innate lymphoid cell (NCR- ILC3) participates in abnormal pathology of lung in cigarette smoking-induced COPD mice

Abstract

Background: Natural cytotoxicity receptor negative innate lymphoid cell (NCR^- ILC3) involves into mucosal homeostasis, inflammation regulation and tissue remodeling. The proportion of NCR^- ILC3 is increased in the lung of smokers with chronic obstructive pulmonary disease (COPD). However, there's still few understandings on the role of NCR^- ILC3 in COPD pathogenesis.

Methods: COPD mice were induced by cigarette smoking. The pathology in lung was detected in histology. The frequency of NCR^- ILC3 (CD3-CD45+RORγt+NkP46-) from murine lung was detected using flow cytometry. IL-17+RORγt+ double positive cells in lung were assessed by double immunofluorescence staining. The protein expressions of epithelial-to-mesenchymal transition (EMT) markers, namely E-cadherin and Vimentin, were assessed using immunohistochemistry staining and western blotting.

Results: The frequency of NCR^- ILC3 in lung was higher in COPD group than controls. The IL-17+RORγt+ cells in lung from COPD mice were more than controls. E-cadherin expression was decreased but Vimentin expression was increased in lung of COPD mice, when compared with controls. The frequency of NCR^- ILC3 in lung tissues were positively correlated with mean linear intercept in lung, destructive index in lung and EMT, respectively.

Conclusions: NCR^- ILC3 could contribute to emphysema and EMT in lung of cigarette smoking-induced COPD, which will provide further understanding on COPD pathogenesis of immune response.

Keywords: COPD; ILC3; NCR negative; cigarette smoking.