To investigate the expression of VEGF, KDR and CD34 in human yolk sac at different stages, we applied immunohistochemical staining and light microscope. It was demonstrated low expression of VEGF, KDR and null expression of CD34 at 3~4 week human yolk sac, strong expression of VEGF, KDR and CD34 at 4~6 week group. Positive cells in the blood island presented large and round, cluster-like or dispersed. And some cells surrounding the blood island showed blood vessel-like structure. At more than 6 weeks after gestation group, the yolk sac expressed VEGF, KDR and CD34 weakly. These findings suggested that the yolk sac could express hematopoietic and angiogenetic associated factors with embryonic development, and contained possibly the hemangioblast which could differentiate into hematopoietic stem cells and vascular endothelial cells.
Wang Yuesi, Jiang Yuzhu, Li Jianyuan, Wang Haiyan, Fan Guangli
. Research on the Expression of Vascular Endothelial Growth Factor and its Receptor
in Human Yolk Sac at Various Developmental Stages[J]. Chinese Agricultural Science Bulletin, 2005
, 21(6)
: 8
-8
.
DOI: 10.11924/j.issn.1000-6850.050608
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