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In Vitro Model of Fetal Human Vessel On-chip to Study Developmental Mechanobiology
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The embryonic human choriocapillaris develops by hemo-vasculogenesis

Takuya Hasegawa1, D Scott McLeod, Imran A Bhutto

  • 1Wilmer Ophthalmological Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.

Developmental Dynamics : an Official Publication of the American Association of Anatomists
|July 27, 2007
PubMed

The purpose of this study was to characterize normal human choroidal vascular development from 6-23 weeks gestation (WG). Markers of endothelial cells (EC) (CD34, CD31, vWf), angioblasts and EC (CD39), leukocytes (CD45), erythroblasts (epsilon chain of hemoglobin, Hb-e), proliferating cells (Ki67), and VEGFR-2 were employed. At 6-7 WG, many erythroblasts were observed within islands of precursor cells in the choriocapillaris layer and others were independent from the islands. Many erythroblasts (Hb-epsilon(+)) were also positive for EC markers and/or VEGFR-2. By 8-12 WG, most of the Hb-epsilon cells had disappeared and vascular lumens became apparent. At 14-23 WG, some EC were proliferating on the scleral side of choriocapillaris in association with forming deeper vessels. In conclusion, embryonic choriocapillaris appears to form initially by hemo-vasculogenesis (blood vessels and blood cells form simultaneously from common precursors) while angiogenesis appears to be the mode of intermediate and large choroidal vessel development in the fetus.

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