An injectable, click-crosslinking (Cx) hyaluronic acid (HA) hydrogel scaffold modified with a bone morphogenetic protein-2 (BMP-2) mimetic peptide (BP) was prepared for bone tissue engineering applications. The injectable click-crosslinking HA formulation was prepared from HA-tetrazine (HA-Tet) and HA-cyclooctene (HA-TCO). The Cx-HA hydrogel scaffold was prepared simply by mixing HA-Tet and HA-TCO. The Cx-HA hydrogel scaffold was stable for a longer period than HA both in vitro and in vivo, which was verified via in-vivo fluorescence imaging in real time. BP acted as an osteogenic differentiation factor for human dental pulp stem cells (hDPSCs). After its formation in vivo, the Cx-HA scaffold provided a fine environment for the hDPSCs, and the biocompatibility of the hydrogel scaffold with tissue was good. Like traditional BMP-2, BP induced the osteogenic differentiation of hDPSCs in vitro. The physical properties and injectability of the chemically loaded BP for the Cx-HA hydrogel (Cx-HA-BP) were nearly identical to those of the physically loaded BP hydrogels and the Cx-HA-BP formulation quickly formed a hydrogel scaffold in vivo. The chemically loaded hydrogel scaffold retained the BP for over a month. The Cx-HA-BP hydrogel was better at inducing the osteogenic differentiation of loaded hDPSCs, because it prolonged the availability of BP. In summary, we successfully developed an injectable, click-crosslinking Cx-HA hydrogel scaffold to prolong the availability of BP for efficient bone tissue engineering.

制备了经骨形态发生蛋白2（BMP-2）模拟肽（BP）修饰的可注射，点​​击交联（Cx）透明质酸（HA）水凝胶支架，用于骨组织工程应用。由HA-四嗪（HA-Tet）和HA-环辛烯（HA-TCO）制备可注射的点击交联HA制剂。仅通过混合HA-Tet和HA-TCO即可制备Cx-HA水凝胶支架。在CX-HA水凝胶支架是两个比HA较长时间稳定在体外和在体内，这是通过验证的体内荧光成像的实时性。BP充当人类牙髓干细胞（hDPSCs）的成骨分化因子。体内形成后Cx-HA支架为hDPSCs提供了良好的环境，水凝胶支架与组织的生物相容性良好。像传统的BMP-2一样，BP在体外诱导hDPSC的成骨分化。Cx-HA水凝胶（Cx-HA-BP）的化学负载BP的物理特性和可注射性与物理负载BP水凝胶的物理特性和可注射性几乎相同，并且Cx-HA-BP制剂在体内迅速形成水凝胶支架。化学负载的水凝胶支架将BP保留了一个多月。Cx-HA-BP水凝胶可更好地诱导负载的hDPSCs的成骨分化，因为它延长了BP的可用性。总而言之，我们成功开发了一种可注射的，点击交联的Cx-HA水凝胶支架，可延长BP在有效的骨组织工程中的可用性。