摘要： PURPOSE. Intravitreal murine lineage-negative bone marrow (BM) hematopoietic cells slow down retinal degeneration. Because human BM CD34t hematopoietic cells are not precisely comparable to murine cells, this study examined the effect of intravitreal human BM CD34t cells on the degenerating retina using a murine model. METHODS. C3H/HeJrd1/rd1 mice, immunosuppressed systemically with tacrolimus and rapamycin, were injected intravitreally with PBS (n ? 16) or CD34t cells (n ? 16) isolated from human BM using a magnetic cell sorter and labeled with enhanced green ?uorescent protein (EGFP). After 1 and 4 weeks, the injected eyes were imaged with scanning laser ophthalmoscopy (SLO)/optical coherence tomography (OCT) and tested with electroretinography (ERG). Eyes were harvested after euthanasia for immunohistochemical and microarray analysis of the retina. RESULTS. In vivo SLO fundus imaging visualized EGFP-labeled cells within the eyes following intravitreal injection. Simultaneous OCT analysis localized the EGFP-labeled cells on the retinal surface resulting in a saw-toothed appearance. Immunohistochemical analysis of the retina identi?ed EGFP-labeled cells on the retinal surface and adjacent to ganglion cells. Electroretinography testing showed a ?at signal both at 1 and 4 weeks following injection in all eyes. Microarray analysis of the retina following cell injection showed altered expression of more than 300 mouse genes, predominantly those regulating photoreceptor function and maintenance and apoptosis. CONCLUSIONS. Intravitreal human BM CD34t cells rapidly home to the degenerating retinal surface. Although a functional bene?t of this cell therapy was not seen on ERG in this rapidly progressive retinal degeneration model, molecular changes in the retina associated with CD34t cell therapy suggest potential trophic regenerative effects that warrant further exploration.