A Primary Study On The Expression And Role Of Wnt10b In Mouse Hair Follicle

Hair follicle(HF) is an important and complex epidermal appendage of skin, and the formation of HF unit requires reciprocal interactions between the epithelium cell and mesenchyme cell.From inside to outside,the structure of HF composes hair shaft(HS), inner root sheath(IRS) and outer root sheath(ORS). With the exception of the ORS,IRS and HS are both derived from differeration of matrix cells. The matrix is a proliferative zone located at the proximal end of the HF surrounding the dermal papilla (DP). Matrix cells which derived from hair follice stem cell(HFSC),display highly proliferative potency and are capable of self-renewal.Multiple signal pathways regulate the morphogenesis and growth of HF together, Wnt signal pathway being the key one. Previous studies have suggested that Wnt signal pathway play crucial role in the HF such as morphogenesis,the activition and maintenance of HFSC,the differentiation of the HS and the formation of human and mouse pilomatricoma. Wnt10b is one of the important number of Wnt family,and it was shown to play various roles in a wide range of biological actions, such as adipogenesis, bone formation, tumor development, and axis determination.At present,Wnt10b is found expression in the developing HF epithelium of the vibrissae and body HF,and it is indicated in the initiated of the HF morphogenesis.However, the founction and properties of Wnt10b to the growth of postnatal HF are not well undersand.In our study,we explorer the expression pattern of Wnt10b in postnatal HF and HF cycle adopting immunochemistry and RT-PCR technology.Moreover, overpression of Wnt10b in the organ culture of vibrissae HF has been manipulated by infected the recombinant adenovirus expressed Wnt10b protein(Adwnt10b).The main result are as follows:1) The expression of Wnt10b in postnatal HF which is strictly special in time and space is firstly detected.We found that Wnt10b was specifically located in the matrix of anagen HF,strong during middle anagen but weak during early and late anagen.Catagen and telogen HF was negative for Wnt10b.During the second early anagen,Wnt10b show posive in the secondary hair germ.Meanwhile,Ki67 show the same expression pattern with Wnt10b.2) AdWnt10b recombinant adenovirus was kindly given by T-C He from Chicago university of American.We stepwise amplificated and purifacated the virus,and the ultimate titer was 109 PFU/ml.3) We cultrued vibrissae HF in vitro,when transfected by the AdWnt10b,the growth of IRS and HS was promoted obviously,the result was in corespondent with our in vivo animal experiment.