Abstract

An Inactivated P. aeruginosa Immunomodulator Restores Imbalanced Epithelial Function Induced by In Vitro RSV Persistent Infection

LiLi Wang, Ling Qin, Huihui Yang, Dan Peng, Qiongshan Ma, Guojun Wu, Shuiping Liu, Qin Xiaoqun

Objectives: Previously, we observed that an inactivated P. aeruginosa vaccine (PPA) inhibited airway allergic inflammation by bronchial administration in an OVA-induced airway hyperresponsiveness animal model. Toinvestigate the underlying mechanism involved, we studied the effects of PPA on epithelial functions in present studies by using an in vitro RSV persistent infection model.

Methods: Real-time PCR was used to examine RSV persistence. Real-time PCR and western blot were used to test the expressions of toll like receptor 4, IL-17A/Th2 signal molecules Act1 and NF-kB negative regulator A20 in BECs. Flow cytometry was used to observe the effects of PPA on cell proliferation and BECs-drived subsets’ differentiation of CD4+T cells.

Results: PPA can stimulate toll like receptor-4 expression, promote cell proliferation in normal and RSV-infected BECs. PPA significantly increased Act1 and A20 expression in BECs inhibited by RSV infection. Also PPA inhibited Th2 and Th17 differentiation and stimulated Th1 differentiation induced by RSV infection.

Conclusions: Our data suggest that the therapeutic mechanism of PPA is partly due to promote bronchial proliferation and maintain the homeostasis of bronchial immunity.