A.. Owaidah, W.. Kafienah, in Reference Module in Biomedical Sciences, 2016

Induced pluripotent stem cells are believed to be an alternative source for ESC in cell based therapies. These cells were found to share similar characteristics to ESCs in terms of unlimited self-renewal capacity and pluripotency. Their capacity to generate cartilaginous tissue was first evident in teratomas in vivo (Takahashi et al., 2007; Takahashi and Yamanaka, 2006; Boulting et al., 2011; Ellis et al., 2009; Yu et al., 2007). This suggested that iPSC exhibit the capacity to differentiate down the chondrogenic lineage. The methods reported on the derivation of chondrocytes from iPSCs were similar to those reported with ESCs, including techniques based on EB formation, co-culture methods with normal chondrocytes and direct differentiation (Guzzo et al., 2013; Wei et al., 2012; Yamashita et al., 2013; Kim et al., 2011).

Despite the fact that iPSC represent an alternative source to ESC in cell-based therapies, the genomic changes that are associated with most of the reprogramming methods hinder the progression towards clinical applications. In 2014, Borestrom and colleagues (Borestrm et al., 2014) showed that reprograming articular chondrocytes using RNA-based methods eliminates the risk of genomic integration and aberrations. In the same study, reprogrammed cells were successfully differentiated into chondrocytes using two different methods. One protocol involved the directed differentiation on monolayer method presented by Oldershaw et al in 2010. The second method involved the generation of cartilage pellets from iPSC with the supplementation of exogenous TGF-1. Chondrogenic differentiation and cartilage nodule formation were again assessed only through chondrogenic gene expression and alcian blue staining without accurate, quantitative matrix analysis.

In conclusion, although there are various methods that can be used to achieve chondrogenic differentiation of both ESCs and iPSCs, current methods only allow for the generation of small scale chondrogenic cultures without methods for competent scale up that permit large-scale tissue engineering for the repair of bona fide cartilage defects.

Read this article:
Induced Pluripotent Stem Cell - ScienceDirect