Embryonic Stem Cells: Where Do We Stand at the Moment?

Abstract

Stem cells are functionally defined as cells that have the ability to self-replicate and generate differentiated cells. They can generate multiple differentiated cell types (multipotent or pluripotent) or produce one type of differentiated cells (unipotent) depending on the replication capacity and potency of stem cells. Today stem cells might have potential application in regenerative medicine, transplantation, treatment of autoimmune, chronic and progressive diseases, as well as disease modelling. Now we are faced with a dilemma between the two types of stem cells, which are more suitable for research and therapeutic use, which will be Embryonic Stem Cells (ESC) or Induced Pluripotent Stem Cells (iPSC)? ESCs represent the gold standard of pluripotency in vitro, which compares all other types of stem cells, but iPSC are more convenient in autologous transplants because of the avoidance of tissue rejection and without ethical concerns. The aim of this paper is presenting the most important characteristics of the ESCs which have therapeutic significance.

Induced pluripotent Stem Cells: Where we are currently?

“…These cells are readily available, they can be used for modelling human genetic diseases in vitro or drug development and screening, individualized regenerative cell therapy, to repair organs and tissues in regenerative medicine, they are less of an ethical issue than ESCs, and they can be isolated from patients themselves and have some genetic background so rejection of the transplant is low. The established iPSCs have a wider variety of differentiation ability and gene expression than ESCs, but a small proportion of these stem cells sometimes show spontaneous differentiation during serial passage [23,24].…”

Questionnaire for evaluating information, knowledge, and attitudes on donation, storage, and application of induced pluripotent stem cells

“…The discovery of Induced Pluripotent Stem Cells (iPSCs) opened the possibilities for reprogramming adult somatic cells back to a pluripotent state in vitro by inducing a forced expression of specific transcription factors so-called Yamanaka factors (i.e.,Oct3/4,Sox2,Klf4, or using the similar set of four transcription factors so-called Thompsons's modification of Yamnaka factors (i.e.,Oct4,Sox2,Nanog,and Lin28) (TAKAHASHI, YAMANAKA, 2006;GURDON, 2006;TAKAHASHI et al, 2007;YU et al, 2007;YAMANAKA, 2008;LOWRY et al, 2008;LANZA, АTALA, 2014;RANČIĆ et al, 2020). These type of stem cells have common features with Embryonic Stem Cells (ESCs) in terms of surface antigen expression, telomerase activity, gene expression, proliferation, and morphology, also could be differentiated into the cells of all three germ layers (LAKO et al, 2010;RAŠČANIN et al, 2019;RANČIĆ et al, 2020).…”

“…iPSCs might have potential application in regenerative medicine (CHENG et al, 2016;WANG et al, 2019;LIU, CHEUNG, 2020), transplantation (SILVESTRO et al, 2020), avoidance of tissue rejection, disease modeling (ATCHISON et al, 2017;MCKINNEY, 2017; VAN DEN BERG et al, 2019), and drug testing (ESCH et al, 2015;CRESPO et al, 2017;PANG, 2020). Because of apparent ethical issues connected with donation and derivation of biomaterials, iPSCs are considered as a research alternative to ethically highly disputed ESCs (MOHAMED, 2018;RAŠČANIN et al, 2019). But it is very important to note that there is a risk of tumorogenesis.…”

“…But it is very important to note that there is a risk of tumorogenesis. More research is needed to fully understand the reprogramming system and how iPSCs can be controlled to produce a sufficient number of cells with high quality and safety requirements for use in stem cells treatments (WAKUI et al, 2017;VOLAREVIC et al, 2018;RAŠČANIN et al, 2019;ZAKRZEWSKI, 2019;RANČIĆ et al, 2020).…”