TGFβ inhibition of yolk-sac-like differentiation of human embryonic stem-cell-derived embryoid bodies illustrates differences between early mouse and human development

Abstract

Transforming growth factor β (TGFβ) plays an important role in development and maintenance of murine yolk sac vascular development. Targeted deletions of Tgfb1 and other components of this signaling pathway, such as Acvrl1, Tgfbr1 and Tgfbr2, result in abnormal vascular development especially of the yolk sac, leading to embryonic lethality. There are significant differences between murine and primate development that limit interpretation of studies from mouse models. Thus, to examine the role of TGFβ in early human vascular development we used the model of differentiating human embryonic stem cell-derived embryoid bodies to recapitulate early stages of embryonic development. TGFβ was applied for different time frames after initiation of embryoid body cultures to assess its effect on differentiation. TGFβ inhibited the expression of endodermal, endothelial and hematopoietic markers, which contrasts with findings in the mouse in which TGFβ reduced the level of endodermal markers but increased endothelial marker expression. The inhibition observed was not due to changes in proliferation or apoptosis. This marked contrast between the two species may reflect the different origins of the yolk sac hemangiogenic lineages in mouse and human. TGFβ effects on the hypoblast, from which these cell lineages are derived in human, would decrease subsequent differentiation of hematopoietic, endothelial and endodermal cells. By contrast, TGFβ action on murine hypoblast, while affecting endoderm would not affect the hemangiogenic lineages that are epiblast-derived in the mouse. This study highlights important differences between early human and mouse embryonic development and suggests a role of TGFβ in human hypoblast differentiation.

TGF-β1 signaling and Krüppel-like factor 10 regulate bone marrow–derived proangiogenic cell differentiation, function, and neovascularization

“…TGF-␤1, in particular, has been characterized as being able to regulate expression of endothelial markers; exogenous administration of TGF-␤1 increased endothelialspecific expression in mouse embryoid bodies and inhibited expression of endodermal markers. 42 However, we did not detect any differences between WT and KLF10 Ϫ/Ϫ PACs for expression of the mesenchymal marker CD105, which was expressed at low levels compared with VEGFR2, after differentiation in vitro (supplemental Figure 7A). In addition, expression of the mesenchymal markers Ng2 and PDGFR were not significantly different after hindlimb ischemia studies in skeletal muscles of WT and KLF10 Ϫ/Ϫ mice (supplemental Figure 7B), suggesting that KLF10 probably does not alter mesenchymal cell expression.…”

Human Embryoid Bodies Containing Nano‐ and Microparticulate Delivery Vehicles

“…Embryoid bodies (EBs) are frequently used as a means to achieve specific stages of embryogenesis in vitro. [1][2][3][4][5] They can be formed from hESC aggregates removed from a feeder layer and cultured in suspension (termed regular EBs). EBs allow cell-cell interaction and they can be rapidly expanded to yield differentiated cells by the use of bioreactors.…”

Human pluripotent stem cells: an emerging model in developmental biology

“…However, species-specific differences also exist. Using human EBs to recapitulate yolk sac development, TGFβ signaling was shown to inhibit endothelial differentiation, the opposite of its role in mice (Poon et al, 2006). Therefore, human EBs provide a valuable model system for studying both conserved and non-conserved mechanisms of early embryogenesis.…”