Localization of immunoglobulin G gamma-chain mRNA-expressing cells in the oviduct of laying and diethylstilbestrol-treated immature hens.

The purpose of this study was to determine the synthetic sites of IgG in the chicken oviduct by localizing IgG gamma-chain mRNA (IgGgamma mRNA)-expressing cells and the effects of estrogen on their population. Paraffin sections of oviducal tissues from laying hens (approximately 57 weeks old) and immature hens (approximately 16 weeks old) with or without diethylstilbestrol (DES) treatment were hybridized by digoxigenin-labeled IgG riboprobes or immunostained for IgG gamma-chain (IgG). Immunoreactive IgG was present in some of the mucosal epithelial cells and the plasma cell-like cells in the stromal connective tissue in all segments of the oviduct. In contrast, IgGgamma mRNA expression was observed only in the plasma cell-like cells in the stromal connective tissues, but not in the cells of mucosal epithelium. In laying hens, the lower end of the oviduct, namely the vagina and uterovaginal junction, contained more IgGgamma mRNA-expressing cells than the other segments. Treatment of immature hens with DES for 3 or 6 days increased the population of both IgGgamma mRNA-expressing cells and IgG-containing cells in the oviducal stroma. These results indicate that IgG is locally produced by plasma cell-like cells in the stroma, but not by the cells of the mucosal epithelium, and estrogen may stimulate the infiltration of IgG-producing plasma cell-like cells into the oviducal stroma.