Animal-derived collagen may contain viruses, and its impurity can cause immunological reactions. Chitosan, always required a neutralization step in fabricating it into the biocompatible tissue engineering scaffolds. To avoid these risks and simplify the production process, a series of recombinant human collagen/carboxylated chitosan (RHC-CHI) based soft hydrogel scaffolds were prepared by crosslinking-induced gelation and then investigated their feasibilities for use as soft tissue engineering scaffolds. The gelation time was optimized by modulating the biopolymer concentration or reaction temperature. The hydrogel swelling, degradation rate, and mechanical properties were also investigated. The results showed that these parameters could be tuned by adjusting either the RHC-to-chitosan ratio or the total polymer concentration. The mechanical properties of the hydrogels were improved by adding chitosan, but excess chitosan reduced the hydrogel mechanical strength and accelerated the degradation speed. Cytotoxicity tests showed that all fabricated soft hydrogels were biocompatible and displayed no cytotoxicity. Cytocompatibility tests and qRT-PCR studies indicated that the hydrogel system promoted the adhesion and proliferation of NIH-3T3 cells, and cellular activities were directly up-regulated by RHC. Finally, our in vivo study proved these hydrogels were able to accelerate the cell infiltration and wound closure. These results show that the soft RHC-CHI hydrogels show promise in soft-tissue engineering.

动物来源的胶原蛋白可能包含病毒，其杂质会引起免疫反应。壳聚糖在将其制成生物相容性组织工程支架时始终需要中和步骤。为避免这些风险并简化生产过程，通过交联诱导的凝胶化制备了一系列基于重组人胶原/羧化壳聚糖（RHC-CHI）的软水凝胶支架，然后研究了它们用作软组织工程支架的可行性。通过调节生物聚合物的浓度或反应温度来优化胶凝时间。还研究了水凝胶的溶胀，降解速率和机械性能。结果表明，可以通过调节RHC与壳聚糖的比例或总聚合物浓度来调整这些参数。加入壳聚糖可改善水凝胶的机械性能，但是过量的壳聚糖降低了水凝胶的机械强度并加快了降解速度。细胞毒性测试表明，所有制备的软水凝胶都具有生物相容性，并且没有细胞毒性。细胞相容性测试和qRT-PCR研究表明，水凝胶系统促进NIH-3T3细胞的粘附和增殖，并且细胞活性被RHC直接上调。最后，我们的 细胞相容性测试和qRT-PCR研究表明，水凝胶系统促进NIH-3T3细胞的粘附和增殖，并且细胞活性被RHC直接上调。最后，我们的 细胞相容性测试和qRT-PCR研究表明，水凝胶系统促进NIH-3T3细胞的粘附和增殖，并且细胞活性被RHC直接上调。最后，我们的体内研究证明，这些水凝胶能够加速细胞浸润和伤口闭合。这些结果表明，软质RHC-CHI水凝胶在软组织工程中显示出希望。