Researchers at the Children’s Hospital of Orange County have created 2 new induced pluripotent stem cell (iPSC) lines for Pompe disease (PD), according to an article published in Stem Cell Research.
The first cell line, CHOCi002-A, was derived from the dermal fibroblasts of a PD patient with the GAA c.258dupC (p.N87QfsX9) frameshift mutation and the c.2227C>T (p.Q743X) nonsense mutation present in compound heterozygosity. The second line, CHOCi003-A, was created from a patient with the c.-32–13T>G splice variant and the c.1826dupA (p.Y609X) frameshift mutation in compound heterozygosity.
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“CHOCi002-A and CHOCi003-A demonstrate the pluripotency characteristics necessary for future use in genome editing strategy testing and disease modeling,” the authors wrote.
The cell lines were reprogrammed using the Sendai viral method to induce pluripotency. Following reprogramming, Sanger sequencing was utilized to confirm that both cell lines still maintained their specific GAA gene mutations.
Reverse transcription PCR (RT-PCR) of each cell line showed a down-regulation in the genes that induce development into ecto-, meso-, or endoderm cells. Expression of self-renewal genes were found to be at similar levels to a pluripotent reference standard. The RT-PCR analyzed 85 genes in total.
SOX2 and NANOG expression was found to be elevated in the iPSCs compared to their parental cells through RT-PCR. Levels of OCT4 were increased for CHOCi002-A but were inconclusive for CHOCi003-A. RT-PCR-based measurements of POU5F1 (OCT3/4) expression for CHOCi003-A were found to be consistent with a pluripotent reference standard, however.
Pluripotency markers including OCT3/4, SOX2, SSEA-4, TRA-1–60, and TRA-1–81 were also observed in the 2 cell lines through immunofluorescence assessment. A common identity between the parental cells and the iPSCs was confirmed at 17 genomic loci using short tandem repeat (STR) analysis. Both cell lines were also confirmed to be free of mycoplasma.
Christensen C, Heckman P, Rha A, Kan SH, Harb J, Wang R. Generation of two induced pluripotent stem cell lines (CHOCi002-A and CHOCi003-A) from Pompe disease patients with compound heterozygous mutations in the GAA gene. Stem Cell Res. Published online May 6, 2023. doi:10.1016/j.scr.2023.103117