CXCL 5 is increased in Candida albicans infected patients and human pulmonary epithelial cells

CXCL5 is critical for recruiting neutrophils and its aberrant production in lung epithelial cells has been confirmed in various mouse models of bacterial infectious diseases. The purpose of this study was to determine whether Candida albicans (C. albicans) upregulates CXCL5 expression of human lung epithelial cells. Here, we demonstrate that serum levels of CXCL5 are significantly increased and positively correlated with serum (1→3)-β-Dglucan (BG) levels in HIV patients with pulmonary candidiasis compared with patients with no evidence of Candida coinfection. Furthermore, serum CXCL5 levels were markedly decreased in patients after treatment with fluconazole for two weeks and positive correlation between serum CXCL5 and BG levels was caused by C. albicans infection. In in vitro cell culture, we further show that C. albicans significantly upregulate CXCL5 expression in both human lung epithelial cell line A549 and bronchial epithelial cell line BEAS-2B by activating PI3K, p38 MAPK, and NF-κB pathways. Together, our study provides novel insight into regulation of CXCL5 chemokine production of lung epithelial cells during C. albicans infection.