Infection in hard tissue regeneration is a clinically-relevant challenge. Development of scaffolds with dual function for promoting bone/dental tissue growth and preventing bacterial infections is a critical need in the field. Here we fabricated hybrid scaffolds by intrafibrillar-mineralization of collagen using a biomimetic process and subsequently coating the scaffold with an antimicrobial designer peptide with cationic and amphipathic properties. The highly hydrophilic mineralized collagen scaffolds provided an ideal substrate to form a dense and stable coating of the antimicrobial peptides. The amount of hydroxyapatite in the mineralized fibers modulated the rheological behavior of the scaffolds with no influence on the amount of recruited peptides and the resulting increase in hydrophobicity. The developed scaffolds were potent by contact killing of Gram-negative Escherichia coli and Gram-positive Streptococcus gordonii as well as cytocompatible to human bone marrow-derived mesenchymal stromal cells. The process of scaffold fabrication is versatile and can be used to control mineral load and/or intrafibrillar-mineralized scaffolds made of other biopolymers.
Bibliographical noteFunding Information:
The authors acknowledge Professor Sven Gorr, Ms. Ruoqiang Chen, and Professor Jakub Tolar from the University of Minnesota for donating S. gordonii, E. coli, and hBM-MSCs, respectively. The authors also acknowledge Neus Bahí Vives from Eurecat for technical assistance with the TGA/DTG analysis. This research was supported by the National Institute for Dental and Craniofacial Research of the National Institutes of Health [grant number R01DE026117 to C. A., T90DE0227232 to N.G.F.], the National Institutes of Health's National Center for Advancing Translational Sciences [Translational Research Development Program-TRDP award to Z.Y. from grant UL1TR002494 ], the Fundamental Research Funds for the Central Universities [grant number 2042020kf0191 to X.Z.], the National Natural Science Foundation of China [grant number 81400506 to Y.Q.] and the Natural Science Foundation of Guangdong Province [grant number 2018B030311040 to Y.Q.]. NGF acknowledges support from a 3 M Science and Technology Fellowship. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Parts of this work were carried out in the University of Minnesota I.T. Characterization Facility, which receives partial support from NSF through the MRSEC program. Confocal laser scanning microscopy was performed at the University of Minnesota – University Imaging Center.
© 2021 [The Author/The Authors]
- Biomimetic mineralization
- Cationic and amphipathic peptides
- Hard tissue