Characterization of Ethanol-Sensitive and Insensitive Fibroblast Cell Lines Expressing Human L1

Abstract: Ethanol inhibits L1-mediated cell-cell adhesion in fibroblast cell lines stably transfected with human L1. Here we show that this action of ethanol is present in only a subset of transfected NIH/3T3 and L cell clonal cell lines. All L1-expressing cell lines had higher levels of cell adhesion than cell lines transfected with empty vector. In all ethanol-sensitive cell lines, L1-mediated adhesion was inhibited by ethanol (IC₅₀ 5–10 m M ), 2 m M butanol, but not 5 m M pentanol. In contrast, ethanol-insensitive cell lines were not inhibited by up to 200 m M ethanol, 2 m M butanol, or 5 m M pentanol. Ethanol sensitivity or insensitivity was a stable property of each cell line and was not associated with differences in electrophoretic mobility, abundance, or cell surface localization of L1. Fab fragments prepared from anti-L1 polyclonal antisera inhibited cell adhesion only in the ethanol-sensitive cell lines. These data suggest that L1 may exist in an alcohol-sensitive or an alcohol-insensitive state that may be governed by host cell factors.