Chondrocyte proliferation and tissue formation enhanced by stromal cell derived factor-1 modified poly-L-lactic acid porous microspheres

Ma Yue; Tan Shiyu; Chu Feiyang; Chen Zhuoqi; Liu Siyu; Liu Wenshuai; Liu Xia

doi:10.12307/2025.443

Abstract：BACKGROUND:The proliferation and phenotypic maintenance of chondrocytes are limited under two-dimensional culture conditions.Porous microspheres serve as scaffolds,providing a three-dimensional culture environment that better mimics in vivo growth conditions.Stromal cell derived factor-1,a homeostatic cytokine with potent chemotactic effects,facilitates cell adhesion and proliferation. OBJECTIVE:To investigate the impact of stromal cell derived factor-1 grafted poly-L-lactic acid porous microspheres on the biological characteristics of chondrocytes and the formation of cartilage tissue. METHODS:(1)The effects of different concentrations of stromal cell derived factor-1 on rabbit chondrocyte proliferation,migration,and phenotypic maintenance were investigated in an in vitro setting.(2)Poly-L-lactic acid porous microspheres were prepared by double emulsion method.Stromal cell derived factor-1 was grafted onto poly-L-lactic acid porous microspheres through carbodiimide reaction.The grafting was verified by enzyme-linked immunosorbent assay and incubation with stromal cell derived factor-1-specific fluorescent antibodies.(3)Rabbit chondrocytes were inoculated on poly-L-lactic acid porous microspheres and grafted on stromal cell derived factor-1 poly-L-lactic acid porous microspheres to detect cell proliferation and adhesion.(4)The methylacrylamide-gelatin-chondrocyte complex(control group),poly-L-lactic acid porous microsphere-methylacrylamide-gelatin-chondrocyte complex(porous microsphere group),and grafted stromal cell derived factor-1 poly-L-lactic acid porous microsphere-methylacrylamide-gelatin-chondrocyte complex(porous microsphere modified group)were implanted under the skin of the back of nude mice,respectively.Samples were collected 8 weeks later and detected using histological staining and qRT-PCR for chondroblast related genes. RESULTS AND CONCLUSION:(1)Compared with 0 and 1 000 ng/mL stromal cell derived factor-1,1 and 500 ng/mL stromal cell derived factor 1 could promote the proliferation and migration of chondrocytes,and enhance the mRNA expression levels of type Ⅱ collagen,elastin,proliferating cell nuclear antigen,and Bcl-2 in chondrocytes.(2)Stromal cell derived factor-1 was successfully grafted onto poly-L-lactic acid porous microspheres with a grafting rate of 93.75%.(3)Compared with poly-L-lactic acid porous microspheres,grafted stromal cell derived factor-1 poly-L-lactic acid porous microspheres promoted the proliferation and adhesion of chondrocytes.(4)After 8 weeks of subcutaneous implantation in nude mice,compared with the control group and the porous microsphere group,the porous microsphere modified group had clearer cartilage lacunae structure,more chondro-specific matrix and type Ⅱ collagen deposition,and increased expression of elastin,type Ⅱ collagen,proliferating cell nuclear antigen,and Bcl-2 mRNA.These findings indicate that stromal cell derived factor-1 grafted poly-L-lactic acid porous microspheres are beneficial to chondrocyte adhesion,proliferation,phenotypic maintenance,and the formation of cartilage tissue in vivo.