Unveiling Telocytes architecture and distribution in the embryonic duodenum of quail (Coturnix japonica): Morphological and ultrastructural insights.

BACKGROUND

Telocytes (TCs) have emerged as a novel and interesting cell population with potential roles in tissue homeostasis and regeneration. The information of their presence and distribution in avian species is limited.

METHODS

Various age stages of quail embryos were collected to identify the morphology and distribution of telocytes within the layers of the duodenum using light microscopy (LM) and Transmission electron microscopy (TEM).

RESULTS

By LM, TCs were recognized by their characteristic morphological features such as a small cell body with prolonged projections known as telopodes. TCs were observed in subepithelial connective tissue, within the villus core, surrounding duodenal crypts, within lamina propria, around blood vessels, among smooth muscle fibers and within the submesothelial layer of the serosa. TEM revealed that TCs in the embryonic duodenum were detected on the 8th day of incubation as a small cellular body primarily occupied with a nucleus. TCs possessed thin, prolonged telopodes, and their morphology varies depending on the number of telopodes, whose shapes vary, ranging from piriform to stellate forms. By hatching, TCs were distributed near goblet cells, blood capillaries, and immune cells, forming extensive cellular networks within both lamina propria and muscular layers.

CONCLUSIONS

TCs and their telopodes were in close contact with various cell types where their localization suggest that they may participate in epithelial proliferation, myogenesis, immune regulation, and angiogenesis. However, these proposed functions remain speculative, and further detailed studies are essential to confirm their roles.