Department of Histology, Faculty of Veterinary Medicine, South Valley University, Qena, 83523, Egypt.
Sci Rep. 2021 Mar 11;11(1):5775. doi: 10.1038/s41598-021-85166-w.
The current study investigated role of telocytes (TCs) in angiogenesis during embryonic development of quail using immunohistochemistry (IHC), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The angiogenic apparatus consisted of TCs, endothelial cells, and macrophages. TCs were identified morphologically by their telopodes and podoms using TEM and SEM and immunohistochemically using CD34, and vascular endothelial growth factor (VEGF). TCs also expressed CD68. TCs formed a three-dimensional network and established direct contact with blood vessels, sprouting endothelial cells, and active macrophages, while exerting their effect through paracrine signaling. VEGF was also expressed by endothelial cells and macrophages. Matrix metalloproteinase-9 (MMP-9) was expressed by TCs, endothelial cells, and macrophages. In conclusion, the expression of VEGF by TCs, endothelial cells, and macrophages is required for the proliferation and migration of endothelial cells and vascular growth. The expression of MMP-9 by TCs, endothelial cells, and macrophages is essential for the degradation of extracellular matrix (ECM) components during neoangiogenesis. Macrophages may facilitate phagocytosis and elimination of the degraded ECM components.
本研究采用免疫组织化学（IHC）、透射电子显微镜（TEM）和扫描电子显微镜（SEM）研究了鹌鹑胚胎发育过程中 telocytes（TCs）在血管生成中的作用。血管生成装置由 TCs、内皮细胞和巨噬细胞组成。TCs 通过 TEM 和 SEM 的 telopodes 和 podoms 以及 CD34 和血管内皮生长因子（VEGF）的免疫组织化学进行形态学鉴定。TCs 还表达 CD68。TCs 形成三维网络，并与血管、发芽的内皮细胞和活跃的巨噬细胞建立直接接触，通过旁分泌信号发挥作用。内皮细胞和巨噬细胞也表达 VEGF。基质金属蛋白酶-9（MMP-9）由 TCs、内皮细胞和巨噬细胞表达。总之，TCs、内皮细胞和巨噬细胞中 VEGF 的表达对于内皮细胞的增殖和迁移以及血管生长是必需的。TCs、内皮细胞和巨噬细胞中 MMP-9 的表达对于新血管生成过程中细胞外基质（ECM）成分的降解是必需的。巨噬细胞可能促进吞噬和消除降解的 ECM 成分。
