Human embryonic stem cells and microenvironment

Abstract

Human embryonic stem cells (hESCs) possess a great potential in the field of regenerative medicine by their virtue of pluripotent potential with indefinite proliferation capabilities. They can self renew themselves and differentiate into three embryonic germ layers. Although they are conventionally grown on mitotically inactivated mouse feeder cells, there are in vitro culture systems utilizing feeder cells of human origin in order to prevent cross-species contamination. Recently established in vitro culture systems suggested that direct interaction with feeder cells is not necessary but rather attachment to a substrate is required to ensure long-term, efficient hESC culture in vitro. This substrate is usually composed of a mixture of extracellular matrix components representing in vivo natural niche. In hESC biology, the mechanism of interaction of hESCs with extracellular matrix molecules remained insufficiently explored area of research due to their transient nature of interaction with the in vivo niche. However, an in vitro culture system established using extracellular matrix molecules may provide a safer alternative to culture systems with feeder cells while paving the way to Good Manufacturing Practice-GMP production of hESCs for therapeutic purposes. Therefore, it is essential to study the interaction of extracellular matrix molecules with hESCs in order to standardize in vitro culture systems for large-scale production of hESCs in a less laborintensive way. This would not only provide valuable information regarding the mechanisms that control pluripotency but also serve to dissect the molecular signaling pathways of directed differentiation for prospective therapeutic applications in the future. J Clin Exp Invest 2014; 5 (3): 486-495

Endometrial cocultured cells in assisted reproduction techniques

“…Bilindiği gibi, insan embriyonik kök hücreleri (İEKH) pre-implantasyon döneminde embriyoda gelişen iç hücre kitlesinden elde edilirler. Son dönemde geliştirilen kültürlerde, İEKH'nin besleyici hücre ile birebir temasına gerek olmadığı, ancak hücre tutunmasını sağlayan substratın varlığının uzun süreli, etkin in vitro İEKH'nin kültürü için gerekli olduğu ileri sürülmüştür [31]. İmplantasyon başarısını artıran sonuçlar için, endometriyal kokültür hücreleri ve İEKH arasındaki hücresel ve moleküler mekanizmaların aydınlatılmasına ihtiyaç vardır.…”