The Human Mesenchymal Stem Cells and the Chick Embryo Chorioallantoic Membrane: The Key and the Lock in Revealing Vasculogenesis

Background/Aim: To analyze the interaction between the human mesenchymal stem cells (hMSC) and the chick embryo chorioallantoic membrane (CAM), in order to assess the still obscure process of vasculogenesis. Materials and Methods: We implanted hMSC onto CAM and we analyzed the morphology and the immunohistochemical profile of CAM. Results: hMSC adhered to CAM, few of them entered the chorionic epithelium and the mesoderm and developed a CD44–/Ki67– status. hMSC stimulated the CAM mesenchymal cells (cMSC) to acquire endothelial and pericyte-like features and to generate cord/capillary-like structures (CLS) in the chorionic epithelium and the mesoderm, but they also entered these structures (CD34+/SMA (smooth muscle actin)+ hMSC). Simultaneously, hMSC induced a process of sprouting angiogenesis in the mesoderm, CD105+ hMSC being identified in the proximity of the angiogenic areas. Conclusion: hMSC and CAM establish a genuine hotspot of vasculogenesis, which may evolve to a valuable experimental model for this research field.