Serum-free and feeder-free culture expansion of human embryonic stem cells

Bovine male germline stem-like cells cultured in serum- and feeder-free medium

Male germline stem cells (mGSCs) presented in male testis are responsible for spermatogenesis during their whole life. However, little information can be found on the culture of bovine mGSCs, and the current culture system needs to be improved. In this study, we compared the effects of several commercial serum-free media and different extra-cellular matrix on the enrichment and cultivation of mGSCs. To find out the best culture condition, the biological characteristics of the cultured cells were evaluated by morphological observation, RT-PCR and immunofluorescent staining. According to the cells' condition in different experiment groups, we found out an efficient cultivation system for bovine mGSCs derived from neonate testis. In this serum- and feeder-free medium, the cultured cells maintained the typical morphology, and expressed specific surface markers of both pluripotent ES cells and mGSCs, including SSEA-1, CD49f, C-MYC, PLZF, GFRα1, LIN28, NANOG, Oct4 and SOX2 in commercial human ESCs medium PeproGrow-hESC + BIO (6-bromoindirubin-3'-oxime). Embryoid bodies, derived from the bovine mGSCs, and were formed by ganging drop culture. The retinoic acid induced bovine mGSCs were positive for Stra8, SCP3, DZAL, EMA1 and VASA, and resembled spermatid cells morphologically. Thus, we found an efficient bovine mGSCs-cultivation system, which is lack in serum and feeder.

Stem cell and tissue engineering in breast reconstruction

Breast cancer worldwide is the most common cancer in women with incidence rate varying from geographic areas. Guidelines for management of breast cancer have been largely established and widely used. Mastectomy is one of the surgical procedures used treating breast cancer. Optionally, after mastectomy, appropriately selected patients could undergo breast reconstruction to create their breast contour. Many techniques have been used for breast reconstructive surgery, mainly implant-based and autologous tissue reconstruction. Even with highly-experienced surgeon and good-quality breast and autologous substitute tissue, still there could be unfilled defect after mastectomy with reconstruction. Stem cell, in particular, adipose-derived stem cell residing within fat tissue, could be used to fill the imperfection providing optimal breast shape and natural feeling of fat tissue. However, whether surgical reconstruction alone or in combination with stem cell and tissue engineering approach be used, the ultimate outcomes are patient safety first and satisfaction second.

Derivation of human embryonic stem cells (hESC)

Stem cells are characterized by their absolute or relative lack of specialization their ability for self-renewal, as well as their ability to generate differentiated progeny through cellular lineages with one or more branches. The increased availability of embryonic tissue and greatly improved derivation methods have led to a large increase in the number of hESC lines.

Xeno-free adaptation and culture of human pluripotent stem cells

Human pluripotent stem cells (hPSCs), including embryonic stem (ES) and induced pluripotent stem (iPS) cells, have been historically cultured in media containing xenogeneic animal components. As hPSC-derived cells and tissues are being developed for human therapies, the application of culture systems to reduce potential immunoreactivity and improve reproducibility becomes increasingly vital. Methods for directly adapting hPSCs to a commercially available culture system free of nonhuman proteins (xeno-free) are described in this chapter.

Current technology for the derivation of pluripotent stem cell lines from human embryos

Technology for the derivation, propagation, and characterization of pluripotent stem cell lines from the human embryo has undergone considerable refinement and improvement since the first published description of human embryonic stem cells in 1998. In particular, there has been extensive effort to optimize protocols and develop defined culture systems with a view toward future clinical applications of embryonic stem cell-derived products. Here, we review the current status of methodology for human embryonic stem cell derivation and culture, and we highlight the challenges that remain for workers in the field.