Immunogenicity of autologous and allogeneic human primary cholangiocyte organoid cellular therapies

Primary human cells cultured in long-term expandable 3D organoid format have great promise as potential regenerative cellular therapies, but their immunogenicity has not yet been fully characterized. In this study, we use in vitro co-cultures and in vivo humanized mouse experimental models to examine autologous and allogeneic immune response to human primary cholangiocyte organoids (PCOs) as treatment for bile duct disorders. Our data demonstrate that PCOs upregulate the expression of human leukocyte antigen (HLA)-I and HLA-II in inflammatory conditions. The allogeneic immune response to PCOs is driven by both HLA-I and HLA-II and is substantially ameliorated by donor-recipient HLA matching. While allogeneic cells display evolving stages of immune rejection in vivo, autologous PCOs induce a low-level immune infiltration into the graft site possibly influenced by acquired mutations in culture, cell viability, and culture matrix. Our findings have important implications for the design and clinical translation of autologous and allogeneic organoid cellular therapies.