Expression of a functional IL-13R alpha 1 by rat B cells

IL-13 mediates its effects through a complex receptor system including IL-4 R alpha and a functional IL-13R alpha1. IL-13 has been reported to have no effects on mouse B cells due to a lack of receptor expression. However, on human B cells a functional IL-13R alpha1 has been described. Here, we ident ified the rat IL-13R alpha1 in order to analyze its expression and function in rat B cells. The expression of IL-13R alpha1 has been shown by the pres ence of mRNA and the corresponding protein in purified rat B cells and in r at hybridoma B cell line. Rat B cells are able to bind IL-13 and to prolife rate when cultured with CD40 ligand and IL-13. In vivo experiments showed t hat administration of IL-13 did enhance IgE production. These results sugge st a direct interaction of rat B cells with IL-13 through a functional rece ptor with an increase of IgE production and provide a relevant model to fur ther study the activity of IL-13 and to better understand its role in human diseases. (C) 2001 Academic Press.