Dr. Xin Zhao is an Associate Professor at the Department of Applied Biology and Chemical Technology, the Hong Kong Polytechnic University (PolyU). Her research interest is on Translational Regenerative Medicine, where she integrates multi-disciplinary approaches including material science, cell biology, engineering and medicine to modulate cell microenvironments, control cell behaviors and generate tissue-engineered organs, for addressing clinical issues.

So far, she has published >100 articles (with h-index of 52 in Google Scholar, 6 of which are ESI highly cited paper) in prestigious journals including Nat. Mater., Proc. Natl. Acad. Sci. USA, Chem. Rev., Mater. Today, Adv. Funct. Mater., Biomaterials, Small. She is recognised in the list of “Highly Cited Researchers 2022” by Clarivate Analytics and “The World’s Top 2% Scientists 2023” by Stanford University, for her significant research impact. She has successfully attracted over 20 grants (⁓23 million) as principal investigator from the Hong Kong RGC (including the highly competitive CRF, NSFC-RGC), HMRF, ITF, NSFC, etc. She is a recipient of the National Science Fund for Excellent Young Scholars 2021, President’s Award-Outstanding Young Researcher 2022, the Mid-Career Award of Chinese Association for Biomaterials 2022, and several other awards. Her research product “Biomimicking Photocrosslinkable Nanocomposite Bone Grafts” has won the Silver Medal at the International Exhibition of Inventions Geneva 2021, 2023 TechConnect Global Innovation Award and the Gold Medal at the 6th China (Shanghai) International Exhibition of Inventions 2023. This research product has secured financial support from the Incu-Bio Programme (HK$ 4 million) from The Hong Kong Science and Technology Parks Corporation and TSSSU-O from Innovation and Technology Comission (HK$ 500 k) for clinical translation of the revolutionary materials. She is also a founding editor of Engineered Regeneration, associate editor of Bio-Des. Manuf., and guest editor for 11 other journals.

Topic title: Triply periodic minimal surface scaffolds for enhanced bone regeneration

Abstract:

Here we report the design and fabrication of high-resolution three-dimensional Triply periodic minimal surface (TPMS) scaffolds embodying biomimicking hyperboloidal topography with different Gaussian curvatures and composed of body inherent β-tricalcium phosphate. The TPMS bone scaffolds show high porosity and interconnectivity. Notably, our TPMS scaffolds not only support the attachment, proliferation, and osteogenic differentiation of human mesenchymal stem cells (hMSCs), but also enhance their angiogenic paracrine function through integrin-mediated focal adhesion kinase (FAK) and mitogen activated protein kinase (MAPK) pathway activation. Compared to conventional scaffolds, the cell-level directional curvatures of our TPMS scaffolds induced nuclear deformation and cytoskeleton reorganization, effectively guiding the fate of cells towards osteogenesis, resulting in significant improvements in bone regeneration. We further coated a polydopamine (PDA)-L-arginine (Arg) network on the TPMS bone scaffolds to modulate the endogenous nitric oxide (NO) gaseous cycle for bone repair. These PDA-Arg coated TPMS scaffolds possessed a large surface area that perpetually produces NO from precursor Arg under the effect of nitric oxide synthase (NOS) of MSCs, allowing simultaneous regulation of osteogenesis, osteoclastogenesis and angiogenesis. Meanwhile, the TPMS scaffolds modified with PDA coating have efficient photothermal conversion and we have realized the precise control of the equilibrium temperature of the TPMS scaffolds (e.g., 37, 39 and 41℃) through low NIR laser power (0.16, 0.2 and 0.24 W). We found that when the scaffold is heated to 39 ~ 41℃, the generated heat can accelerate bone tissue regeneration, by promoting the synthesis of heat shock proteins (HSP) proteins and enhancing the expression of extracellular signal-regulated kinase 1/2 (ERK1/2). We believe that these well-defined features grant our TPMS scaffolds a head start towards a safer and more efficient bone graft with notable clinical translation potential.