To investigate the construction, cytotoxicity and histocompatibility of genipin-chitosan collagen scaffold for yak achilles tendon.

The tendon of yak was used as material for crude extraction by enzyme-acid method, and collagen was separated and purified by high performance liquid chromatography. Crosslinking agent was added to construct genipin-chitosan collagen scaffold for yak achilles tendon and genipin-chitosan standard type I collagen scaffold. L929 mouse embryonic fibroblasts were inoculated on the orifice plates of the two kinds of scaffolds and cultured for 1, 3, 5, 7, 9 and 11 days, respectively. Cell morphology was observed under inverted microscope. Cell count kit-8 was used for cell proliferation/toxicity test and cell viability was calculated. The two kinds of protein scaffolds were transplanted into the deep fascia layer on the two sides of the spine of the same rat respectively, and samples were taken on 3, 5, 7 and 9 days after transplantation, fixed with 10% neutral formalin solution, embedded with paraffin, sectioned, stained with hematoxylin and eosin. The degradation of collagen and the growth of blood vessels were observed under the microscope. Data were processed with t test.

Cultured for 1, 3, 5, 7, 9, 11 days, the cell viability of L1929 mouse embryonic fibroblasts, which were inaculated into the genipin-chitosan collagen scaffold for yak achilles tendon and genipin-chitosan standard type I collagen scaffold, were respectively (3.14±0.04) %, (2.17±0.13) %, (2.60±0.11) %, (1.78±0.02) %, (1.64±0.32) %, (1.12±0.02) %; (2.96±0.07) %, (2.08±0.10) %, (2.68±0.14) %, (1.75±0.02) %, (1.84±0.01) %, (1.14±0.01) %, the differences were not statistically significant (t=-2.15, -1.31, 1.22, -1.27, 1.51, 0.54; P=0.06, 0.22, 0.25, 0.25, 0.16, 0.63). In vivo histocompatibility test, all the animals survived, the surgical incision healed well, there were no changes of acute inflammation, local effusion and abscess. After 3, 5, 7 and 9 days of transplantation, the genipin-chitosan collagen scaffold for yak achilles tendon and genipin-chitosan standard type I collagen scaffolds were not degraded, and local tissues grew into the cross-linked scaffolds. Inflammatory cell proliferation and red blood cells and new small blood vessels were observed in the scaffolds.

The genipin-chitosan collagen scaffold for yak achilles tendon has good biosafety and potential as tissue engineering scaffold.