Effect of Ethanol on Rhinovirus-16 Infection in A549 Cells

Kim, Hyung Seok; Lee, Bong Jae; Lee, Si Hyung; Kwon, Hyun Ja; Park, Hyung Wook; Jang, Yong Ju

Abstract

BACKGROUND AND OBJECTIVES: Rhinovirus (RV) enters into the airway epithelial cells via the membrane bound receptor ICAM-1. The epithelial cells produce chemotactic cytokines after RV infection. The purpose of this study is to investigate the effect of ethanol on promoting RV infection in airway epithelial cells by increasing the ICAM-1 level and causing a reversible damage in epithelial barrier function.
SUBJECTS AND METHOD
We pretreated various concentrations of low non-cytotoxic ethanol to A549 cells before RV infection and investigated the effect of ethanol on RV infection. The changed in epithelial barrier function was assessed by transepithelial electrical resistance as measured by voltmeter. Effect of ethanol on ICAM-1 expression was assessed by flow cytometry. Epithelial cytokine response was evaluated using ELISA technique. The level of viral replication was expressed as viral titer, which was determined through viral culture on MRC-5 cells.
RESULTS
Ethanol increased ICAM-1 mean fluorescence intensity and the viral titer according to the pretreated ethanol concentrations. But increment of ICAM-1 was inconsistent with increase of viral titer and vise versa. In ethanol treated cells, the production of cytokines was increased and it was consistent with increase of viral titer. Ethanol treatment had no effect on transepithelial resistance.
CONCLUSION
Ethanol pretreatment enhanced the ICAM-1 expression, viral replication and RV induced cytokine secretion in A549 cells. But we could not prove the association of RV infection with ICAM-1 expression induced by ethanol. Transepithelial resistance was not changed after ethanol treatment.