Background: While the use of neural stem/progenitor cells has been reported as a promising therapeutic approach for spinal cord injury, direct comparison of adult primary animal spinal cord NSPCs have not been compared to human NSPCs under the same conditions to characterize intrinsic differences between human/animal NSPC response to inflammatory/regenerative factors. Methods: To mimic post-injury inflammation, primary-derived NSPCs from adult humans, pigs, and rats were treated with pro-inflammatory factors.To direct regeneration, NSPCs were treated with retinoic acid, platelet-derived growth factor or bone morphogenic protein-(BMP4) to induce neurons, oligodendrocytes or astrocytes, respectively.Cultures were treated for 7 or 14 days and characterized by immunocytochemistry. Results: Pro-inflammatory factors promoted more astrogenesis in rat and pig NSPCs compared to human NSPCs and induced neuronal differentiation in human NSPCs. RA increased neurogenesis of human and rat NSPCs, PDGFα increased oligodendrocyte differentiation of rat NSPCs, and BMP4 increased astrogenesis of human and rat NSPCs Conclusions: For the first time, differences in response of human, pig and rat primary NSPCs to inflammatory and regenerative factors have been identified. Better understanding of these differences is essential to improving the successful translation of regenerative therapies to humans.