Cell Therapy Using Induced Pluripotent Stem Cells or Somatic Stem Cells: This is the Question

Abstract

A lot of effort has been developed to bypass the use of embryonic stem cells (ES) in human therapies, because of several concerns and ethical issues. Some unsolved problems of using stem cells for human therapies, excluding the human embryonic origin, are: how to regulate cell plasticity and proliferation, immunological compatibility, potential adverse side-effects when stem cells are systemically administrated, and the in vivo signals to rule out a specific cell fate after transplantation. Currently, it is known that almost all tissues of an adult organism have somatic stem cells (SSC). Whereas ES are primary involved in the genesis of new tissues and organs, SSC are involved in regeneration processes, immuno-regulatory and homeostasis mechanisms. Although the differentiating potential of ES is higher than SSC, several studies suggest that some types of SSC, such as mesenchymal stem cells (MSC), can be induced epigenetically to differentiate into tissue-specific cells of different lineages. This unexpected pluripotency and the variety of sources that they come from, can make MSC-like cells suitable for the treatment of diverse pathologies and injuries. New hopes for cell therapy came from somatic/mature cells and the discovery that could be reprogrammed to a pluripotent stage similar to ES, thus generating induced pluripotent stem cells (iPS). For this, it is necessary to overexpress four main reprogramming factors, Sox2, Oct4, Klf4 and c-Myc. The aim of this review is to analyze the potential and requirements of cellular based tools in human therapy strategies, focusing on the advantage of using MSC over iPS.

SFRP2 enhanced the adipogenic and neuronal differentiation potentials of stem cells from apical papilla

“…Due to the special characteristics of stem cells, stem cell therapies, including but not limited to tissue regeneration and immune regulation, have come to the forefront of modern medical science. Nonetheless, several difficulties need to be resolved, such as the modulation of cell plasticity and proliferation, the prospective harmful side effects, and the elimination of transplanted cells (Somoza and Rubio, ). Numerous factors are being investigated in the regulation of cell plasticity and to enhance the success rate of tissue regeneration.…”

TGFβ3 secretion by three-dimensional cultures of human dental apical papilla mesenchymal stem cells

“…These approaches are based mainly on the development of skin substitutes using scaffolds and cells, which are implanted after damage. Mesenchymal stem cells (MSCs) have great therapeutic potential because of their multilineage differentiation capacity (Somoza and Rubio, ), ease of isolation from multiple adult tissues (da Silva Meirelles et al ., ; Huang et al ., ) and secretion of growth factors (GFs) (Caplan and Dennis, ; Meirelles et al , ). This trophic activity has emerged as the main therapeutic effect of MSCs when implanted for tissue regeneration purposes (Meirelles et al , ).…”

Embryonic Stem Cells

“…Similar to adult tissue-derived cell sources, histo-incompatibility may also limit the widespread use of hESC-based therapies, since careful HLA matching will be needed to avoid immune rejection. Of note, the advent of induced pluripotent stem cells (iPSCs) could one day alleviate both the ethical and histoincompatibility issues surrounding hESC use [1,2]. iPSCs can be generated from a person's own mature somatic cells and through the process of reprogramming, be turned back into a pluripotent state for use as a patient-specific renewable cell source with broad differentiation capabilities.…”