Functional xenogeneic hematopoietic cells maintaining donor-dominant identity and immune tolerance enable therapy

The clinical supply of hematopoietic cells is severely constrained by the limitations of donor donation and inefficient in vitro generation. While generating these cells within interspecies chimeras presents a groundbreaking alternative, the fundamental biological properties and therapeutic potential of the resulting xenogeneic hematopoietic cells remain poorly characterized.

We generated xenogeneic hematopoietic cells in rodent models via blastocyst complementation and bone marrow transplantation. A comprehensive comparative analysis of these cells was conducted using single-cell RNA sequencing and proteomics. Their functional efficacy was rigorously evaluated through reverse transplantation into a series of donor-species disease models, including hemorrhagic anemia, thalassemia, thrombocytopenia, and leukemia.

Bone marrow transplantation yielded significantly higher chimeric efficiency than blastocyst complementation. Xenogeneic hematopoietic cells, including red blood cells, platelets, and white blood cells, exhibited a transcriptional and proteomic profile that was dominantly donor-specific. Crucially, these cells did not elicit significant immune rejection upon reverse transfusion. Functionally, xenogeneic red blood cells rescued models of hemorrhagic anemia and thalassemia, platelets alleviated thrombocytopenia, and xenogeneic T cells engineered with a chimeric antigen receptor effectively suppressed leukemia progression. Furthermore, the implantation of xenogeneic hematopoietic cells partially reconstituted splenic morphology and function in immunodeficient recipients.

Our study provides the first comprehensive functional validation of xenogeneic hematopoietic cells generated in interspecies bioreactors. We definitively show that these cells possess donor-like molecular identities, evade immune rejection, and serve as effective "seed cells" to rescue a wide spectrum of hematologic diseases. This work establishes a transformative paradigm for utilizing interspecies chimeras to overcome critical shortages in transfusion and cellular therapies.