Antimicrobial and bioactive nanoparticle functionalized protein coatings

Implant-associated infections remain a persistent clinical challenge, underscoring the urgent need for innovative implant optimizations that can prevent microbial infection while promoting osseointegration to improve patient outcomes. We develop and characterize new implant coatings based on protein nanofibers and analyze these coatings by investigating temporal interactions of osteoblasts, macrophages, and microbes, with a focus on miRNA-mediated regulation. This allows us to gain in-depth insights into the properties of protein nanofibers as well as the temporal regulation of osteoblast activity, immune responses, and antimicrobial effects of optimized implant coatings.

The concept of the “race for the surface” has evolved beyond a simple competition between osteoblasts and microbes to include the critical influence of the host's inflammatory response upon implantation. Early immune events, particularly macrophage activation, shape the biological outcome at the implant interface. MicroRNAs (miRNAs) are key post-transcriptional regulators of various biological processes. However, their role in bone infection and osteointegration is not fully understood.

The goal of our project is to develop and test protein coatings for biomaterials that inhibit bacterial adhesion while promoting osteoblast growth. Therefore, self-assembled protein nanofiber coatings and scaffolds will be designed that mimic the structure and properties of the extracellular matrix. Furthermore, the scaffolds will be functionalized with antibacterial peptides and nanoparticles to fine-tune their antibacterial and osteoblast-promoting properties.

Micrographs of protein nanofiber coatings. A. Fluorescence microscopy and AFM pictures of albumin aggregates that self-assembled under different pH. Scale bar: 10 µm. Adapted with permission. 2026, Xi et al. (https://doi.org/10.1016/j.colsurfb.2026.115954) under license CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). B. AFM picture of lysozyme fibrils on mica. C. SEM pictures of SaOS-2 cells on lysozyme fibril coatings on Ti-6Al-4V.
Image: Linus Reck

Using cell biological and microbiological approaches, we will study optimized material compositions. Our focus will be on miRNA profiling to clarify the temporal regulation of osteoblast activity, immune responses, and microbial colonization during the initial stages of implant integration.

A. SEM picture of SaOS-2 cells on titanium disks. B. CLSM picture of SaOS-2 cells on coated titanium disks (staining: DAPI + Phalloidin). C. LM picture of SaOS-2 cells in culture. D. SEM image of S. aureus on polished Ti-6Al-4V. E. SEM image of S. aureus on 500 µg/mL human serum albumin coating on Ti-6Al-4V.
Image: Philipp Stempfle, Mandana Azari & Heidrun Garlipp

Research Highlight

Thus far, the findings demonstrate that an optimized albumin coating can enhance host cell responses and reduce bacterial colonization. This dual effect offers potential for improving bone regeneration and long-term implant integration. The coatings will be optimized by converting albumin monomers into nanofibers and functionalizing them with nanoparticles. In addition, nanofibers derived from other proteins will be tested. miRNA profiling and validation in organoid culture as well as ex vivo studies are planned.

Related Publications

Azari, M., Della Bella, E., and Wildemann, B., (2026)
Functionalizing Biomaterials for Osseointegration - MicroRNAs at the Crossroads of Bone Formation and Immune Modulation
Bone & Joint Research 15, 864-879. https://doi.org/10.1302/2046-3758.157.BJR-2025-0576.R1External link

Oral, E., Chisari, E., Choe, H., Cichos, K.H., Coenye, T., Coraca-Huber, D.C., Drage, L., Hamilton, J.L., Jensen, L.K., Jennings, J.A., Moriarty, F., Muthukrishnan, G., Nishitani, K., Norton, N., Pervizi, J., Priddy, L., Saeed, K., Schwarz, E.M., Siverino, C., Sekar, A., Trobos, M., and Wildemann, B. (2026)
The 2025 International Consensus Meeting on Musculoskeletal Infection: Research Priorities and Future Directions
Journal of Orthopaedic Research® 44, e70179. https://doi.org/10.1002/jor.70179External link

Xi, Z., Zerdani, M., Trautmann, J., Neumann, C., Wiedemann, C., Nowotnick, A.G., Wolf, N., Reck, L., Figge, M.T., Svensson, C.-M., Turchanin, A., Eggeling, C., Hellmich, U.A., and Jandt, K.D. (2026)
Ethanol-driven structural transitions of human serum albumin and surface-assisted 2D network formation on Ti-6Al-4V: A kinetic-morphological map
Colloids Surf. B Biointerfaces 267, 115954. https://doi.org/10.1016/j.colsurfb.2026.115954External link

Azari, M., Xi, Z., Makarewicz, O., Jandt, K.D., and Wildemann, B. (2026)
Effects of concentration-dependent human serum albumin coating on cellular response and bacterial inhibition in vitro
TERMIS 2026, Palma de Mallorca, Spain

Azari, M., Xi, Z., Jandt, K.D., and Wildemann, B. (2025)
The Role of Surface-Bound Protein Concentration in Osteoblast Proliferation
BioMAT 2025, Weimar, Germany

Erenay, B., Özcolak, B., Öztatli, H., Erkoc-Biradli, F.Z., Jandt, K.D., and Garipcan, B. (2025)
Engineering a platform combining decellularized ECM and native bone surface topography for investigating osteoblastic function
Biomed. Mater. 21, 015006. https://doi.org/10.1088/1748-605X/ae2558External linkExternal link

Xi, Z., Azari, M., Wildemann, B., and Jandt, K.D. (2024)
Antimicrobial Protein Nanofiber Coatings for Enhanced Titanium Integration
MSE 2024, Darmstadt, Germany

Blondel, M., Machet, C., Wildemann, B., Abidine, Y., and Swider, P. (2024)
Mechanobiology of bacterial biofilms: Implications for orthopedic infection
J. Orthop. Res. 2024, 1-9. https://onlinelibrary.wiley.com/doi/10.1002/jor.25822External linkExternal link

Nowotnick, A.G., Xi, Z., Jin, Z., Khalatbarizamanpoor, S., Brauer, D.S., Löffler, B., and Jandt, K.D. (2024)
Antimicrobial Biomaterials Based on Physical and Physicochemical Action
Adv. Healthcare Mater. 2402001. https://doi.org/10.1002/adhm.202402001External link

Mandal, S., Tannert, A., Ebert, C., Guliev, R.R., Ozegowski, Y., Carvalho, L., Wildemann, B., Eiserloh, S., Coldewey, S.M., Löffler, B., Silva, L.B., Hoerr, V., Tuchscherr, L., and Neugebauer, U. (2023)
Insights into S. aureus-Induced Bone Deformation in a Mouse Model of Chronic Osteomyelitis Using Fluorescence and Raman Imaging
Int. J. Mol. Sci. 24, 9762. https://doi.org/10.3390/ijms24119762External linkExternal link

Azari, M., Jandt, K.D., Wildemann, B., and Xi, Z. (2023)
Antimicrobial Proteins and Protein based Materials - A Review
BioMAT 2023, Weimar, Germany

Project Team

Prof. Dr. Klaus D. Jandt
Friedrich Schiller University Jena · Material Science de
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Prof. Dr. Britt Wildemann
Jena University Hospital · Clinic for Trauma-, Hand- and Reconstructive SurgeryExternal link
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Mandana Azari
Jena University Hospital · Clinic for Trauma-, Hand- and Reconstructive SurgeryExternal link
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Linus Reck
Friedrich Schiller University Jena · Material Science de
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Philipp Stempfle
Jena University Hospital · Clinic for Trauma-, Hand- and Reconstructive SurgeryExternal link
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Zhongqian Xi
Friedrich Schiller University Jena · Material Science de
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Dr. Diana Freitag
Jena University Hospital · Clinic for Trauma-, Hand- and Reconstructive SurgeryExternal link
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Dr. Kristin Griebenow
Friedrich Schiller University Jena · Material Science de
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Nils Wolf
Friedrich Schiller University Jena · Material Science de
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Dr. Chuan Yin
Friedrich Schiller University Jena · Material Science de
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