Transplantation Of Neurogenin2 Transfected Adipose Derived Stem Cell As A Neuroprotective Therapy For Spinal Cord Injury In Rats

Research background:Traumatic spinal cord injury(SCI)is a catastrophic and disabling event that results in severe motor,sensory,and autonomic dysfunction.The costs of SCI are enormous for the affected individual with a significant impact on quality of life and life expectancy.Cell transplantation therapy,which utilizes stem,progenitor,primary cells or stem cell(SC)derivatives to replace or repair impaired organs or tissues,have evoked much attention among researchers as the potential to promote repair and functional plasticity in the SCI.In recent years,adipose stem cells(ADSCs)as a mesenchymal stem cells,autologous drawn convenient and flexible,has a wide range of clinical research prospects.The ADSCs are easily acquired from multiple cell sources and reproductive.However,previous studies have indicated that the ability and capacity of ADSCs for neural differentiation are limited.Neurogenin-2(Ngn2)is a member of the basic helix-loop-helix(bHLH)transcription factor family,plays an essential role in neurogenesis in the dorsal telencephalon and commits multipotent precursors to the neuronal fate.In this study,Ngn2 could be used to convert somatic cell into a neuron fate and benefit for central nervous system recovery.Thus,the current study sought to investigate whether transplantation of Ngn2-ADSCs could displayed the characteristics of neurogenic cells and improve functional recovery in an experimental rat model of SCI.Methods:1.ADSCS isolated from the epididymal fat pads in SD rats by means of differential attachment were cultured vitro and subjected to adipogenic induction.By ADSCs adipogenic and associated antigens CD29,CD44 and CD45 testing to prove their stem cell characteristics.2.For infections,Cells in passage 3 were plated and incubated with lentiviruses.Ngn2-ADSCs stable cell gene expression,and the ability to detect directional differentiation into neural cells by immunofluorescence in vitro.3.Nine days after contusion,48 rats were randomly assigned to the following three groups(n=16/group):the DMEM control,ADSCs,and Ngn2-ADSCs groups.The rats were re-anaesthetised,partially dissociated ADSCs/Ngn2-ADSCs(approximately 1*106cells/5ul in cell culture medium without added growth factors)were injected into the lesion epicenter using a glass pipette fitted to a 10-ul Hamilton syringe.4.The hind-limb motor function of all rats was recorded using the Basso,Beattie,and Bresnahan(BBB)locomotor rating scale for 8 weeks.Haematoxylineosin(HE)staining,immunohistochemistry were performed.Results:1.ADSCs successfully extracted from rat adipose tissue in the groin,access proliferation and passaged in vitro.2.The purpose of lentiviral gene Ngn2 be efficiently transduced into ADSCs and stable expression in vitro differentiation into neural cells and expressed neuronal specific markers.3.Successful injection Ngn2-ADSCs in the damaged area,and the transplanted cells by immunofluorescence observed in rats survival,migration and differentiation.4.Ngn2-ADSCs transplantation group in motor function score,glial scar formation after spinal cord injury and pathological changes in the secretion of neurotrophic factor BDNF and VEGF were significantly better than the other groups.Conclusions:1.ADSCs cells stably expressing a gene Ngn2 rat nerve cells can be directed to improve their ability to differentiate.2.Ngn2-ADSCs after transplantation can effectively survive and differentiate into nerve cells,inhibit glial scar formation,reduce spinal cord injury voids,increase BDNF and VEGF expression,and to improve recovery of motor function in SCI rats in a more efficient way than that with ADSCs alone.