Hair Follicle Stem Cells In Repair Of Sciatic Nerve Injury

Objective：peripheral nerve injury and nerve defect can be caused by Mechanicalfactors,physical factors,chemical factors and Tumor. but there is no a good clinicaltreatment for peripheral. The emergence of tissue engineering technology and celltransplantation technology which take stem cells as "seed cells" greatl greatlyenriched and developed the research of peripheral nerve injury recovery;The stemcells have constant proliferation and differentiation potential. However, most adultstem cells face numerbers of problem,such as unclear location, ethical issues andimmunologic incompatibility etc. So hair follicle stem cells (HFSC)as a source ofrelatively abundant and accessible, active, pluripotent adult stem is expected to be animportant "seed cell". In our study, we show that transplanted hair follicle stem cellscan enhance the regrowth of severed sciatic, and so as provide animals experimentalbasis for useing hair follicle stem cell to treat peripheral nerve injury.Methods:1. Hair follicle stem cells were isolated, cultured in vitro,purified byadherence screening method.2. the HFSC of third passage were collected for transplantationexperiments after identification by immunocy to fluorescence staining of CK19,β1-integrin,nestin.3. Hair follicle stem cells were isolated and cultured in vitro. Thirty sixhealthy rats were selected to prepare sciatic nerve crush injury models with clampingmethod. Subsequently, rats were randomly divided into transplantation group andcontrol group, with eighteen rats in each group. Rats in the transplantation groupunderwent transplantation of FSC at nerve injured sites;while, the same volumephosphate puffered saline (PBS) was injected into rats in the control group。4.3,7,14,21,28,60days after surgery Sciatic nerve function index (SFI)were detected.5.4,8weeks after surgery histological staining of nerves were test.Result:1.Though Inverted microscope,rough and flat polygons Hair follicle stem cells were lay in bottle as Paving road stone. These cells connect tightly, cellnucleus were big and locate in one side of the cells some of which were Binucleatecells. A week later,the cells increase and overspreads the culture dish closely.Subsequently, we detected the expression of positive markers of hair follicle stemcells in our cultured cells.nestin, CK19and β1-integrin were strong expressed incytoplasm and cell membrane.The rate of positive cell were more than95%.2. After surgery the surgery side legs were unable to stand up and thetoes were unable to open; the surgery side legs in each group were swelling andulcer.six weeks after sugery, the surgery side toes in stem cell group could open acertain degee,but in the control group they open not obviously;8weeks later thesurgery side toes in stem cell group could almost all open.3.the function of sciatic nerve the in The stem cell group were earlierrecovery than the control group,through Sciatic nerve function index.4. Hematoxylin and eosin (H&E) staining of sciatic nerve injury aftertransplantation in each group at week4and8. The amout of sciatic nerve nervefibers and cells were increase in each group,but the arrangement of the nerve fibers inthe stem cells group were more regular than the control group.these nerve fibers instem cells group reconstructed in certain line though which the signal conductionwas more conducive. Though histological staining of nerves, We could see thatcells.nestin, CK19and β1-integrin were expressed in the nerve cell of stem cellgroup, these positive cell proliferated together as time goes and the nerve fibers werebetter conjuction.