The Immunohistochemical Demonstration of the Dlx-5, HLX and TLX1 Proteins in the Bovine Gastric Compartments Throughout Prenatal Development

The homeobox gene subfamily members Dlx-5, HLX and TLX1proteins are known to regulate several embryonic development processes, including body axis formation, limb development and organogenesis, and play critical roles in cell proliferation and differentiation. This study was designed to investigate the localisation and expression density levels of Dlx-5, HLX and TLX1 proteins in cells of bovine stomach compartments during gestation and to compare the immunoexpression between the stomach compartments. A total of 30 foetuses, morphologically normal, from each period of gestation (10 foetuses from each period), were used in the study. The foetuses were classified according to their age, determined by the crown–rump length (CRL) measurement, into the first (69–89 days/10 foetuses), second (99–178 days/10 foetuses) and third (188–269 days/10 foetuses) periods of gestation. Then, the stomach (rumen, reticulum, omasum and abomasum) of foetuses from all three periods was processed with routine histological procedures, subjected to Crosman's triple staining, and an immunohistochemistry procedure was applied. As a result, it was observed that Dlx-5, HLX and TLX1 were expressed in the stomach compartments throughout gestation, with different expression intensities in cells, and the expression intensity was stronger in epithelial cells compared to stromal and smooth muscle cells. These results suggest that Dlx-5, HLX and TLX1 proteins may contribute to the structure of the bovine stomach and play a role in cell division, proliferation and differentiation, as well as in histogenesis, of the stomach.