Generation of hypoimmunogenic induced pluripotent stem cells by CRISPR-Cas9 system and detailed evaluation for clinical application

In order to expand the promise of regenerative medicine using allogeneic induced pluripotent stem cells (iPSCs), precise and efficient genome editing of human leukocyte antigen (HLA) genes would be advantageous to minimize the immune rejection caused by mismatches of HLA type. However, clinical-grade genome editing of multiple HLA genes in human iPSC lines remains unexplored. Here, we optimized the protocol for good manufacturing practice (GMP)-compatible CRISPR-Cas9 genome editing to deplete the three gene locus (HLA-A, HLA-B, and CIITA genes) simultaneously in HLA homozygous iPSCs. The use of HLA homozygous iPSCs has one main advantage over heterozygous iPSCs for inducing biallelic knockout by a single gRNA. RNA-seq and flow cytometry analyses confirmed the successful depletion of HLAs, and lineage-specific differentiation into cardiomyocytes was verified. We also confirmed that the pluripotency of genome-edited iPSCs was successfully maintained by the three germ layers of differentiation. Moreover, whole-genome sequencing, karyotyping, and optical genome mapping analyses revealed no evident genomic abnormalities detected in some clones, whereas unexpected copy number losses, chromosomal translocations, and complex genomic rearrangements were observed in other clones. Our results indicate the importance of multidimensional analyses to ensure the safety and quality of the genome-edited cells. The manufacturing and assessment pipelines presented here will be the basis for clinical-grade genome editing of iPSCs

Collagen-derived dipeptide prolyl-hydroxyproline promotes osteogenic differentiation through Foxg1

Abstract Prolyl-hydroxyproline (Pro-Hyp) is one of the major constituents of collagen-derived dipeptides. We previously reported that Pro-Hyp promotes the differentiation of osteoblasts by increasing Runx2, osterix and Col1α1 mRNA expression levels. Here, to elucidate the mechanism of Pro-Hyp promotion of osteoblast differentiation, we focus on the involvement of Foxo1 in osteoblast differentiation via Runx2 regulation and the role of Foxg1 in Foxo1 regulation. The addition of Pro-Hyp had no effect on MC3T3-E1 cell proliferation in Foxo1- or Foxg1-knockdown cells. In Foxo1-knockdown cells, the addition of Pro-Hyp increased ALP activity, but in Foxg1-knockdown cells, it had no effect on ALP activity. An enhancing effect of Pro-Hyp on the Runx2 and osterix expression levels was observed in Foxo1-knockdown cells. However, no enhancing effect of Pro-Hyp on osteoblastic gene expression was observed when Foxg1 was knocked down. These results demonstrate that Pro-Hyp promotes osteoblastic MC3T3-E1 cell differentiation and upregulation of osteogenic genes via Foxg1 expression

Comparison of long-term outcomes after trans-catheter aortic valve implantation between patients primarily diagnosed by cardiac murmur and those diagnosed by other reasons.

Careful auscultation is the first step to diagnose aortic stenosis (AS). The aim of this study was to compare clinical outcomes following transcatheter aortic valve implantation (TAVI) between the patients primarily diagnosed by heart murmur and those diagnosed by other reasons. We retrospectively included 258 patients who underwent TAVI in our medical center, and divided those into the murmur group (n = 81) and the other-reason group (n = 177) according to the primary reason for AS diagnosis. The primary endpoint was the major adverse cardiovascular and cerebrovascular events (MACCE), which was defined as the composite of cardiovascular death, hospitalization due to acute decompensated heart failure, and disabling stroke. The murmur group included younger patients than the other-reason group (82.8 year-old vs. 84.0 year-old, P = 0.02). History of AF was more frequently observed in the other-reason group than in the murmur group (21.5% vs. 7.4%, P <0.01). STS score and logistic EuroSCORE were lower in the murmur group than in the other-reason group (STS: 4.7% vs. 7.2%, P <0.01, logistic EuroSCORE: 8.3% vs. 11.2%, P <0.01). The median follow-up period was 562 days. MACCE was more frequently observed in the other-reason group than in the murmur group (27.7% vs. 9.9%, Log Rank P <0.01). The multivariate COX hazard analysis revealed that the AS patients primarily diagnosed by heart murmur was inversely associated with MACCE (HR 0.38, 95%CI 0.17-0.86, P = 0.020). Among AS patients who underwent TAVI, the patients primarily diagnosed by heart murmur were significantly associated with favorable long-term clinical outcomes