CRISPR-Cas9-driven antigen conversion of clinically relevant blood group systems

Area of Science:

• Regenerative Medicine
• Hematology
• Gene Editing Technologies

Background:

• Blood transfusions rely on compatible blood types, which can be difficult to find due to antigen diversity.
• Chronically transfused patients face alloimmunization risks from repeated exposure to foreign red blood cells (RBCs).
• ABO and Rhesus (Rh) blood group systems are critical in transfusion medicine due to their immunogenicity and polymorphism.

Purpose of the Study:

• To investigate the potential of cultured red blood cells (cRBCs) combined with gene editing to address blood transfusion challenges.
• To develop a method for producing antigen-negative RBCs to improve transfusion accessibility.

Main Methods:

• Utilized CRISPR-Cas9 gene editing to knock out genes responsible for AB and Rh antigen expression in hematopoietic stem and progenitor cells (HSPCs).
• Employed a virus- and selection-free approach for gene editing.
• Cultured edited HSPCs to produce erythroid cells (cRBCs).

Main Results:

• Achieved near-complete conversion to O and RhNull phenotypes in engineered cRBCs.
• Confirmed phenotype changes using standard hemagglutination and flow cytometry.
• Demonstrated the feasibility of producing antigen-negative cRBCs.

Conclusions:

• CRISPR-Cas9 gene editing can effectively eliminate AB and Rh antigens from cRBCs.
• This approach holds promise for expanding transfusion accessibility for patients with unmet needs, particularly those requiring rare blood types.
• Combining gene-edited cRBCs with existing protocols could revolutionize transfusion medicine.