The research of transgenic human nucleus pulposus cell transplantation in the treatment of lumbar disc degeneration

Abstract

The present study determines whether the in vivo injection of TGFβ1 and CTGF mediated by AAV2 to transfect nucleus pulposus cells in degenerative lumbar discs can reverse the biological effects of rhesus lumbar disc degeneration. A total of 42 lumbar discs obtained from six rhesus monkeys were classified into three groups: experimental group, control group, and blank group. Degenerative lumbar discs were respectively injected with double gene-transfected human nucleus pulposus cells using minimally invasive techniques. Immumohistochemical staining, RT-PCR, and western blot were performed to observe the biological effects of double genetransfected human nucleus pulposus cells in degenerative lumbar discs on rhesus lumbar disc degeneration. At 4, 8, and 12 weeks after the transplantation of nucleus pulposus cells, the expression levels of TGF-ß1, CTGF, proteoglycan mRNA, and type-II collagen were detected by RT-PCR. The values of immumohistochemical staining and RT-PCR in the experimental group increased at 8 weeks, decreased with time at 12 weeks, and remained greater than the values in the control group, and the differences were statistically significant (P < .05). The western blot revealed that the values in the experimental group decreased with time, but remained greater than those in the PBS control group and blank control group, and the differences were statistically significant (P < .05). The double gene-transfection of human nucleus pulposus cells in degenerative lumbar discs mediated by rAAV2 can be continuously expressed in vivo after transplantation in lumbar discs of rhesus monkeys, and promotes the synthesis of proteoglycan and type II collagen, achieving the treatment purpose. K E Y W O R D S

Cell sources proposed for nucleus pulposus regeneration

“…This review aims to focus on the choice of cell source for regenerative approaches and thus will not discuss the combinations with biomaterial and growth factors which have been reviewed elsewhere. 44,[91][92][93][94][95][96][97][98][99][100] NP tissue also contains a population of NP progenitor cells 98,[101][102][103] which have been suggested to be NPderived stem cells although their full characterization as stem cells has not been completed. NP progenitors in vitro are presented as elongated spindle shape cells, 104 which are positive for Tie2 and express stem cell genes (eg, Sox2, Oct3/4, Nanog, CD133, Nestin, and neural cell adhesion molecule).…”

“…However, the culture of isolated cells prevents all cell-matrix interactions and signaling and thus, NP cells could act differently when cultured in in vivo systems. 133 NP cells transplantation into in vivo models have also been investigated and studies have shown that the transplanted NP cell remain viable for a number of weeks and months; allogeneic expanded rtNP cells remained viable for 4 weeks in a rat model 134 ; in a canine model, cryopreserved autologous cNP cells were observed at 12 weeks 115 and 12 months of allogeneic expanded cNP cells 62 ; xenogeneic transplantation of a hNP established cell line were sustained in a rabbit model for 8 and 24 weeks, 98,135 12 weeks in a monkey model 100 and 12 weeks in a canine model. 116 Interestingly, transplanted NP cells were mainly localized in the injected zone, with observation of cells migrating into the inner AF in canine and rat treated models.…”

“…NP cells within the mature human IVD are rounded and situated within a lacunae, * the NP cell produces abundant proteoglycans and collagen type II, with phenotypic makers of Forkhead Box F1 (FOXF1), paired box 1 (PAX1), Keratin 19 (KRT19) among others. 44 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 NP tissue also contains a population of NP progenitor cells 98 , 101 , 102 , 103 which have been suggested to be NP‐derived stem cells although their full characterization as stem cells has not been completed. NP progenitors in vitro are presented as elongated spindle shape cells, 104 which are positive for Tie2 and express stem cell genes (eg, Sox2, Oct3/4, Nanog, CD133, Nestin, and neural cell adhesion molecule).…”

Expression of Oocyte Vitellogenesis Receptor Was Regulated by C/EBPα in Developing Follicle of Wanxi White Goose

“…The tissue section and immunohistochemical procedure were performed according to Wang et al [ 19 ]. The primary antibody of OVR (1:1000, RD Systems, Catalog: AF2258, Minneapolis, MN, USA), and the secondary antibody (1:1000, Servicebio, Catalog: GB23204, Wuhan, China) were used to identify the expression and localization of OVR in each follicle level through the specific light to dark brown staining.…”