Transplantation of rat-derived microglial cells promotes functional recovery in a rat model of spinal cord injury

• Main Authors: Dewei Kou, Tianmi Li, Hong Liu, Chuansheng Liu, Yanwei Yin, Xing Wu, Tengbo Yu
• Format: Article
• Language: English
• Published: Associação Brasileira de Divulgação Científica 2018-07-01
• Series: Brazilian Journal of Medical and Biological Research
• Subjects: Microglia; Spinal cord injury; Transplantation; CD68; OX42
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2018001000603&lng=en&tlng=en

This study evaluated the effect of microglia transplantation on neurological functional recovery in rats subjected to traumatic spinal cord injury (SCI). The rat model of SCI was established using a weight drop device. Forty SCI rats were randomly divided into the microglia group and the saline group. Then, rat-derived microglial cells or normal saline was injected into the injured site 7 days after surgery. The Basso-Beattie-Bresnahan (BBB) score, inclined plate test, and motor-evoked potentials (MEPs) were applied to assess the recovery of motor function. Hematoxylin and eosin (H&E) staining was used to assess the therapeutic effect. Microglia transplantation significantly improved BBB scores and functional scores at 2, 3, 4, 6, and 8 weeks after surgery compared to saline injection (P<0.05). Meanwhile, a prolonged MEP latency and decreased MEP amplitude were observed at 4 and 8 weeks in the microglia group (P<0.05). Histological analysis showed less damage and better prognosis in SCI rats of the microglia group. BrdU+ cell tracing experiments showed that microglia were recruited to the injured area of the spinal cord at 7 and 14 days after transplantation. The intensity of immunofluorescence was increased in CD68+ and OX42+ microglia at 2 days, 1 week, and 2 weeks, and then decreased at 3 and 4 weeks after transplantation in the microglia group. The transplantation of activated microglia played a key role in promoting the recovery of spinal cord function in a rat model of SCI.