Tracing genomic instability in induced mesenchymal stromal cell manufacture: an integration-free transfection approach

TL;DR

The study shows that iPS cells used to make mesenchymal stem cells often develop genetic changes, highlighting the need for careful genomic monitoring.

Contribution

The novel contribution is comparing genomic instability in iPS cells generated via Sendai virus versus episomal vectors.

Findings

SV-iPS cells showed more copy number alterations and SNVs compared to Epi-iPS cells.

TP53 mutations were identified in SV-derived iPS cells, indicating increased genomic instability.

SV-iPS cells exhibited upregulated chromosomal instability-related genes in late passages.

Abstract

Here we systematically investigated genomic alterations from the initiation of induced pluripotent stem (iPS) cell generation to induced mesenchymal stromal/stem cell differentiation. We observed a total of ten copy number alterations (CNAs) and five single-nucleotide variations (SNVs) during the phases of reprogramming, differentiation and passaging. We identified a higher frequency of CNAs and SNVs in iPS cells generated using the Sendai virus (SV) method compared with those generated with episomal vectors (Epi). Specifically, all SV-iPS cell lines exhibited CNAs during the reprogramming phase, while only 40% of Epi-iPS cells showed such alterations. Additionally, SNVs were observed exclusively in SV-derived cells during passaging and differentiation, with no SNVs detected in Epi-derived lines. Gene expression analysis revealed upregulation of chromosomal instability-related genes in late-passage SV-iPSCs, further indicating increased genomic instability. Notably, TP53 mutations were identified, underscoring the vulnerability of the gene and the critical need for careful genomic scrutiny when preparing iPS cells and derived cell lines.

This study explores the potential of using induced pluripotent stem (iPS) cells to create mesenchymal stem (MS) cells for medical treatments. iPS cells can be reprogrammed from regular cells and can become any cell type, including MS cells, which are important for tissue repair. However, a concern is that iPS cells might develop genetic changes that could affect their safety. Here researchers investigated these genetic changes during the creation and growth of iPS cells and their transformation into MS cells using advanced techniques such as chromosomal microarray and next-generation sequencing, alongside conventional methods. The study found that iPS cells often develop genetic alterations, which can persist as they are turned into MS cells. The results suggest that while iPS cells hold promise for regenerative medicine, careful monitoring of genetic stability is crucial. Future research should focus on improving methods to ensure safety of iPS cell-derived therapies.

This summary was initially drafted using artificial intelligence, then revised and fact-checked by the author.

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