Zhao Da-Wang, Zuo Kang-Qing, Wang Kai, Sun Zhao-Yang, Lu Yu-Peng, Cheng Lei, Xiao Gui-Yong, Liu Chao
Department of Orthopedics, Qilu Hospital of Shandong University, Jinan 250012, PR China; Cheeloo College of Medicine, Shandong University, Jinan 250012, PR China; Institute of Stomatology, Shandong University, Jinan, Shandong 250012, PR China.
School of Materials Science and Engineering, Shandong University, Jinan 250061, PR China.
Mater Sci Eng C Mater Biol Appl. 2021 Jan;118:111512. doi: 10.1016/j.msec.2020.111512. Epub 2020 Sep 16.
Titanium (Ti) and its alloys are believed to be promising scaffold materials for dental and orthopedic implantation due to their ideal mechanical properties and biocompatibility. However, the host immune response always causes implant failures in the clinic. Surface modification of the Ti scaffold is an important factor in this process and has been widely studied to regulate the host immune response and to further promote bone regeneration. In this study, a calcium-strontium-zinc-phosphate (CSZP) coating was fabricated on a Ti implant surface by phosphate chemical conversion (PCC) technique, which modified the surface topography and element constituents. Here, we envisioned an accurate immunomodulation strategy via delivery of interleukin (IL)-4 to promote CSZP-mediated bone regeneration. IL-4 (0 and 40 ng/mL) was used to regulate immune response of macrophages. The mechanical properties, biocompatibility, osteogenesis, and anti-inflammatory properties were evaluated. The results showed that the CSZP coating exhibited a significant enhancement in surface roughness and hydrophilicity, but no obvious changes in proliferation or apoptosis of bone marrow mesenchymal stem cells (BMMSCs) and macrophages. In vitro, the mRNA and protein expression of osteogenic related factors in BMMSCs cultured on a CSZP coating, such as ALP and OCN, were significantly higher than those on bare Ti. In vivo, there was no enhanced bone formation but increased macrophage type 1 (M1) polarization on the CSZP coating. IL-4 could induce M2 polarization and promote osteogenesis of BMMSCs on CSZP in vivo and in vitro. In conclusion, the CSZP coating is an effective scaffold for BMMSCs osteogenesis, and IL-4 presents the additional advantage of modulating the immune response for bone regeneration on the CSZP coating in vivo.
钛(Ti)及其合金因其理想的机械性能和生物相容性,被认为是牙科和骨科植入的有前景的支架材料。然而,宿主免疫反应在临床上总是导致植入失败。钛支架的表面改性是这一过程中的一个重要因素,并且已经被广泛研究以调节宿主免疫反应并进一步促进骨再生。在本研究中,通过磷酸盐化学转化(PCC)技术在钛植入物表面制备了钙 - 锶 - 锌 - 磷酸盐(CSZP)涂层,该涂层改变了表面形貌和元素组成。在此,我们设想通过递送白细胞介素(IL)-4来促进CSZP介导的骨再生的精确免疫调节策略。使用IL-4(0和40 ng/mL)来调节巨噬细胞的免疫反应。评估了其机械性能、生物相容性、成骨能力和抗炎特性。结果表明,CSZP涂层在表面粗糙度和亲水性方面有显著增强,但骨髓间充质干细胞(BMMSCs)和巨噬细胞的增殖或凋亡没有明显变化。在体外,在CSZP涂层上培养的BMMSCs中,成骨相关因子如碱性磷酸酶(ALP)和骨钙素(OCN)的mRNA和蛋白表达明显高于裸钛表面。在体内,CSZP涂层上没有增强的骨形成,但巨噬细胞1型(M1)极化增加。IL-4可以在体内和体外诱导M2极化并促进CSZP上BMMSCs的成骨。总之,CSZP涂层是BMMSCs成骨的有效支架,并且IL-4在体内对CSZP涂层上的骨再生具有调节免疫反应的额外优势。