Universal donor cells

A process for generating universal donor cells, the process comprising:

• (a) modifying stem cells by inserting a nucleotide sequence encoding programmed death-ligand 1 (PD-L1) within or near a gene encoding beta-2 microglobulin (B2M), thereby generating PD-L1 positive cells;
• (b) enriching for PD-L1 positive cells;
• (c) modifying the PD-L1 positive cells from (b) by inserting a nucleotide sequence encoding HLA class I histocompatibility antigen, alpha chain E (HLA-E) within or near a gene encoding thioredoxin interacting protein (TXNIP), thereby generating PD-L1, HLA-E double positive cells;
• (d) enriching for PD-L1, HLA-E double positive cells;
• (e) single cell sorting to select for PD-L1, HLA-E double positive cells;
• (f) characterizing cells from (e) as universal donor cells;
• and
• (g) freezing the universal donor cells for long term storage.