CRISPR/Cas9 Ribonucleoprotein Complex-Mediated Efficient B2M Knockout in Human Induced Pluripotent Stem Cells (iPSCs)

Area of Science:

• Stem cell biology
• Immunology
• Genetics

Background:

• Induced pluripotent stem cells (iPSCs) offer potential for regenerative medicine and cell replacement therapy.
• Immune rejection due to human leukocyte antigen (HLA) mismatch is a significant hurdle in allogeneic transplantation.
• Generating universal stem cells by eliminating HLA expression is a key strategy to overcome immunogenicity.

Purpose of the Study:

• To present an effective genome editing strategy for knocking out the beta-2-microglobulin (B2M) gene in iPSCs.
• To achieve depletion of HLA class I (HLA-I) molecules on the surface of iPSCs.
• To provide a validated protocol for generating and analyzing B2M-knockout iPSCs.

Main Methods:

• Utilized genome editing technology to target and knockout the B2M gene in iPSCs.
• Employed flow cytometry for validation of HLA-I depletion on B2M-knockout iPSCs.
• Conducted genotypic analysis to assess potential off-target mutations.

Main Results:

• Successfully generated B2M-knockout iPSCs, resulting in the depletion of HLA-I molecules.
• Validated the knockout efficiency and absence of HLA-I expression using flow cytometry.
• Confirmed the genetic integrity of the modified iPSCs with analysis of potential off-target sites.

Conclusions:

• The developed genome editing approach provides a viable method for generating universal iPSCs by eliminating HLA-I expression.
• This strategy holds promise for advancing cell replacement therapies by reducing immune rejection.
• The protocol is adaptable for knocking out other genes in iPSCs and various cell types.