Alcohol Functionally Upregulates Toll-Like Receptor 2 in Airway Epithelial Cells
Alcoholism: Clinical and Experimental Research Published Online: 22 Dec 2008

Alcoholics are known to have more severe airway diseases of the lung, such as bronchitis. Little is known about why this phenomenon is observed. We hypothesized that alcohol may modulate Toll-like receptor 2 (TLR2), which regulates inflammation caused by gram-positive bacteria.

Alcohol, at biologically relevant concentrations (25 to 100 mM), caused a 2 to 3-fold time- and concentration-dependent increase in TLR2 mRNA in normal human bronchial epithelial cells and 16HBE 14o- cells. Western blots for TLR2 revealed a qualitative increase in TLR2 protein in cells exposed to 100 mM alcohol. FACS showed that TLR2 was quantitatively increased on the surface of airway epithelial cells that were exposed to alcohol. Airway cells that were primed with alcohol produced nearly twice as much IL-8 in response to 40 ng of peptidoglycan than naive cells.

Alcohol upregulates TLR2 message and protein in the airway epithelium. This leads to exaggerated inflammation in response to environmental stimuli that would normally be well tolerated in airway epithelial cells. This may be a partial explanation of why alcoholics have more severe airway disease than nonalcoholics.

Read Full Abstract

Request Reprint E-Mail: jsisson@unmc.edu
____________________________________________________