猪后肾帽状间充质细胞发育为肾小球足细胞的过程

目的:探讨中国实验用小型猪肾小球足细胞的发育过程。方法:应用过碘酸-希夫氏染色观察中国实验用小型猪胚胎不同时间点(胚胎28d至出生后21d,以周为单位,共17个时间点)肾小球发育过程中的形态学变化。应用免疫荧光技术检测猪胚肾不同阶段(帽状间充质、肾小囊体、逗号形体、"S"形体、毛细血管袢期肾小球、成熟肾小球)足细胞的发育过程。结果:猪在胚胎第28天(E28d)后肾已开始发育,可见典型的帽状间充质、肾小囊体、逗号形体和"S"形体;E35d可见肾小球形成,包括近皮质的不成熟肾小球以及近髓质的成熟肾小球。胚肾组织免疫荧光染色显示:胚肾早期足细胞标志物WT1表达于Six2阳性的后肾帽状间充质细胞,相继表达于肾小囊体、整个逗号形体、逗号形体尾部以及"S"形体下端,最终局限于肾小球足细胞。结论:中国实验用小型猪的足细胞来源于Six2阳性的后肾帽状间充质细胞,经过肾小囊体、逗号形体、"S"形体、毛细血管袢期肾小球阶段,发育成为成熟肾小球的足细胞。

Process of Metanephric Cap Mesenchyme Cells Developing into the Glomerular Podocytes in Pigs

Objective ：To investigate the process of metanephric cap mesenchyme cells developing into the glomerular podocytes in Chinese experimental miniature pigs. Methods：Periodic acid -Schiff staining （PAS） was used to identify the morphological changes of glomerular development in Chinese experimental miniature pig at different time points （from embryonic day 28 to 112, and postnatal days 1,7, 14 and 21 ）. Immunofluorescence staining was applied to detect the development of glomerular podocytes at different developmental stages ： Cap mesenchyme, Renal vesiclee, Comma - shaped body, S - shaped body, Glomemli of capillary loop stage and mature stage）. Results：PAS staining revealed that metanephric development in pigs began at E28d, at which point the typical cap mesenchyme, renal vesicle, comma -shaped body and S- shaped body could be detected; Glomeruli were formed at E35d, including the immature glomeruli, which were located below the nephrogenic zone, and the mature glomeruli, which were located juxt- amedullary. Immunofluorescence staining showed that WT1 （podocyte marker） expression was observed in the metanephric cap mesenchyme cells which were Six2 - positive, and then in the renal vesicle, the comma - shaped body, the tail of the comma - shaped body, the lower aspect of the S - shaped body and the glomerular podocytes, in succession. Conclusion ： The porcine podocytes arise from metanephric cap mesenchyme cells which are Six2 - positive, and these cells specialize into the renal vesicle, the comma - shaped body, the S -shaped body and differentiate into mature podocytes.