Human Leukocyte Antigen Class I and II Knockout Human Induced Pluripotent Stem Cell–Derived Cells: Universal Donor for Cell Therapy

Abstract

Background We aim to generate a line of “universal donor” human induced pluripotent stem cells (hi PSC s) that are nonimmunogenic and, therefore, can be used to derive cell products suitable for allogeneic transplantation. Methods and Results hi PSC s carrying knockout mutations for 2 key components (β2 microglobulin and class II major histocompatibility class transactivator) of major histocompatibility complexes I and II (ie, human leukocyte antigen [HLA] I/ II knockout hi PSC s) were generated using the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR associated protein 9 (Cas9) gene‐editing system and differentiated into cardiomyocytes. Pluripotency‐gene expression and telomerase activity in wild‐type ( WT ) and HLAI / II knockout hi PSC s, cardiomyocyte marker expression in WT and HLAI / II knockout hi PSC ‐derived cardiomyocytes, and assessments of electrophysiological properties (eg, conduction velocity, action‐potential and calcium transient half‐decay times, and calcium transient increase times) in spheroid‐fusions composed of WT and HLAI / II knockout cardiomyocytes, were similar. However, the rates of T‐cell activation before (≈21%) and after (≈24%) exposure to HLAI / II knockout hi PSC ‐derived cardiomyocytes were nearly indistinguishable and dramatically lower than after exposure to WT hi PSC ‐derived cardiomyocytes (≈75%), and when WT and HLAI / II knockout hi PSC ‐derived cardiomyocyte spheroids were cultured with human peripheral blood mononuclear cells, the WT hi PSC ‐derived cardiomyocyte spheroids were smaller and displayed contractile irregularities. Finally, expression of HLA ‐E and HLA ‐F was inhibited in HLAI / II knockout cardiomyocyte spheroids after coculture with human peripheral blood mononuclear cells, although HLA ‐G was not inhibited; these results are consistent with the essential role of class II major histocompatibility class transactivator in transcriptional activation of the HLA ‐E and HLA‐F genes, but not the HLA ‐G gene. Expression of HLA ‐G is known ...

Generation of hypoimmunogenic human pluripotent stem cells

“…Ablating the highly polymorphic HLA class Ia and class II molecules is necessary to prevent the activation of cytotoxic CD8 + T and CD4 + T helper cells. Recently, the power of the CRISPR/Cas9 genome-editing system provided us and others with a tool to interfere with HLA class I expression in human pluripotent stem cells (hPSCs) or hematopoietic cells by knocking out the accessory chain beta-2-microglobulin (B2M) (3)(4)(5)(6)(7) and to eliminate HLA class II expression by targeting its transcriptional master regulator, CIITA (7,8). However, the deletion of B2M also prevents the surface expression of the nonpolymorphic HLA class Ib molecules HLA-E and HLA-G, which are required to maintain NK cell tolerance (9,10).…”

Ectopic hepatocyte transplantation cures the pig model of tyrosinemia

“…However, healthy allogeneic hepatocytes could be transplanted in cases where partial hepatectomy is contraindicated, such as in acute liver failure or severe cirrhosis, which would require additional support via established immune suppression protocols. Possible future sources of hepatocytes include universal donor hepatocytes, IPS-derived hepatocytes, and HLA-matched farmed hepatocytes (30)(31)(32). In our study hepatocytes were transplanted into pig mesenteric lymph nodes using an open technique due to the paucity of suitable peripheral lymph nodes in the neonatal pig, but the same procedure could foreseeably be performed into central or peripheral lymph nodes in humans via a percutaneous or endoscopic ultrasound-guided technique, as described previously.…”

Stem cell-derived cell sheet transplantation for heart tissue repair in myocardial infarction

“…Deuse [97] and his team established a nonimmunogenic iPSC line with the major histocompatibility complex (MHC) class I and II genes inactivated and CD47 overexpressed. Mttapally et al [98] knocked out the B2M and CIITA genes, which are crucial for the display of human leukocyte antigen (HLA) class I and II proteins at the cellular surface, to provide a source of universal donor iPSCs for the treatment. In summary, by knocking out the relevant genes for MHC I/II and HLA I/II, it is possible to construct cell lines that are more suitable for transplantation.…”