Chromosomal Stability during Stem Cell Culture: Recent Status and Its Implications a
Journal of Agricultural, Biological and Environmental Sciences | Year-2014
One of the key issues impeding the application of human embryonic stem cells (hESCs) in regenerative medicine is the occurrence of karyotypic instability of hESCs during long term culture. Stem cells grown in culture are exposed to strong selection pressures that often results in genomic alterations, varying in size from point mutations to large chromosomal aberrations, trisomies and monosomies. Different culturing conditions may affect the nature and the frequency of the acquired aberrations;
... uired aberrations; however no culturing technique is immune to genomic instability. The current techniques to evaluate the genomic integrity of stem cells are mostly based on direct cytogenetic and DNA-based analyses; traditional karyotype, spectral karyotyping, array-based molecular analyses of genomic integrity etc. The potential use of aberrant or instable stem cells in cell therapy is obviously hindered as there is increased tumorigenicity risk. It is then important to optimize culturing conditions, cryo-storage and monitoring systems to be applied to the newly derived as well as existing cell lines to decipher any genetic and epigenetic alterations. It was also found that reduced oxygen to physiological levels and additions of antioxidants can be employed as possible strategies to lower oxidative stress and decrease chances of chromosomal transformation. The manual and mechanical dissection are preferentially used during hESCs sub-culturing as being less aggressive and better preserve the genome integrity.