Immunohistochemical localization of epidermal growth factor system in the lung of the Japanese quail (Coturnix coturnix japonica) during the post-hatching period

Abstract

The purpose of this study is to determine the possible changes in the localization of the four Epidermal Growth Factor Receptors and three ligands in quail lungs from the first day of hatching until the 125th after hatching using immunohistochemical methods. Immunohistochemical results demonstrated that four EGFRs and their ligands are chiefly located in the cytoplasm of cells. Additionally, ErbB4, AREG, and NRG1 are localized to the nucleus and nucleolus, but EGF is present in the nucleolus. ErbB2 was also found in the cell membrane. In the epithelium of secondary bronchi, the goblet cells only exhibited ErbB1 and ErbB2, whereas the basal and ciliated cells exhibited EGFRs and ligands immunoreactivity. The atrial granular cells displayed moderate levels of ErbB1-ErbB3 and EGF and strong levels of ErbB4, AREG, and NRG1 immunoreactivity. While the squamous atrial cells and squamous respiratory cells of air capillaries and endothelial cells of blood capillaries exhibited moderate to strong ErbB2, ErbB4, AREG, and NRG1 immunoreactivity, they had negative or weak ErbB1, ErbB3, and EGF immunoreactivity. The expression levels of ErbB2-ErbB4, EGF, AREG, and NRG1 were also detected in fibroblasts. Although ErbB2 was highly expressed in the bronchial and vascular smooth muscle cells, weak expression of ErbB1, ErbB3, AREG and EGF and moderate expression of ErbB4 and NRG1 were observed. Macrophages were only negative for ErbB1. In conclusion, these data indicate that the EGFR-system is functionally active at hatching, which supports the hypothesis that the members of EGFR-system play several cell-specific roles in quail lung growth after hatching.

Finding Expression of MUC1 and MUC4 in the Respiratory System of the Iraqi Common Quail (Coturnix coturnix)

“…Therefore, our study which focused on various types of mucins, particularly MUC1 and MUC4, in the respiratory system of the Iraqi common quail is consistent with these previous reports. Studies conducted on Japanese Quail indicated the presence of variable mucin types, including both neutral and acidic mucins, which exhibited changes corresponding to the post-hatching period of the Quail [44]. These findings are consistent with our results, which confirm the presence of a mixture of mucins, with acidic mucins being predominant over neutral mucins, and this predominance diminishes towards the lungs.…”