Objective:To express and purify recombinant human collagen type Ⅲ and evaluate its properties.Methods:The recombinant genetic engineering strain pET30a(+)-1880/pACYCDuet-hy726/bL21(DE3) was constructed to stably co-express recombinant human type Ⅲ collagen (rhCol) and prolyl hydroxylase. rhCol was prepared and purified by E. coli high-density fermentation, salting out and column chromatography protein purification technology. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to determine the purity of rhCol. The N-terminal amino acid sequences of rhCol were determined by automatic protein polypeptide sequencing instrument. The hydroxyproline content of rhCol was determined by ultraviolet spectrophotometry. The cellular compatibility of rhCol was evaluated by MTT assay. Results:The final wet weight of high-density fermentation was about 200 g/L. The expression level was about 3 g/L. The purity of rhCol by affinity chromatography was over 95%. The results showed that the hydroxyproline content of rhCol was 11.44%, and the rhCol products have good water solubility and cell compatibility.Conclusions:RhCol can be widely applied to the field of skin care and biomedicine as an excellent biological material.

Hydrogel is a kind of three-dimensional matrix scaffold material with chemical or physical cross-linked structure, with high moisture retention and high water absorption, but insoluble in water. Because of its good biocompatibility and the ability to imitate the natural cytoplasmic matrix, hydrogel has broad practical significance and application prospects in the fields of tissue engineering and biomedicine. Nerve tissue engineering is a fast-growing field that is expected to address severe neurological diseases. Choosing the right matrix scaffold material to promote neural cell differentiation and axon growth is critical to the overall design of nerve tissue engineering. Hydrogels have been widely used to deliver neurotrophic factors, antagonists of nerve growth inhibitors and other neural growth-promoting agents to tissues to improve the difficult regeneration of the nervous system, and have proven to be excellent matrix scaffold materials for neural tissue engineering. In this review paper, a variety of hydrogel systems that have been applied to neuro-related research were classified and discussed, and their advantages and disadvantages were analyzed. The prospects and challenges of hydrogels in neural tissue engineering were also discussed.