Functional Recovery and in Vivo Cell Tracking after Human Adipose Tissue-Derived Stem Cells Therapy for Experimental Spinal Cord Injury

Abstract

Introduction The use of human adipose tissue-derived stem cells (hADSC) as therapy in spinal cord injury (SCI) is a promising approach for the recovery of motor function of injured patients. This study aims to evaluate the effects of hADSC, applied to the cauda equina in an animal model of blunt spinal trauma, on their motor function. A secondary aim is to analyze cell migration toward the injury site. Method All samples were collected after an informed consent had been obtained in accordance with guidelines for research involving human subjects, and with the approval of the ethics committee (approval number 769). A total of 40 Wistar rats were anesthetized, injured at Th10 using the NYU impactor device and randomly divided into four groups: Group A, animals were submitted to one culture medium injection immediately after injury; group B, animals were submitted to two culture medium injections, immediately after and 7 days postlesion; group C, animals were submitted to one cell injection (1 × 106 cells) immediately after injury and group D, animals were submitted to two cell injections, immediately after and 7 days postlesion. Standard animal care, according to the university's protocol was maintained for 40 days with motor analysis every 72 hours using the Basso, Beattie, and Bresnahan (BBB) scale. Some animals were transplanted with luc gene-transduced cells to evaluate cell migration, which was assessed by in vivo bioluminescence images of animals in groups C and D (IVIS Lumina II). Results A statistically significant recovery of motor function was observed in animals transplanted with hADSC compared with the control group ( p = 0.007 for one injection protocol, p = 0.005 for the two injection protocol). No differences were observed between one and two injection protocols ( p = 0.13). Bioluminescence analysis revealed cell migration to the injury site after injection. Conclusion hADSC injected at the cauda equina migrate toward the injury site and promote significant motor recovery.