Abstract
The fibrotic encapsulation of implants involves the mechanical activation of myofibroblasts and of pro-fibrotic transforming growth factor beta 1 (TGF-β1). Here, we show that both softening of the implant surfaces and inhibition of the activation of TGF-β1 reduce the fibrotic encapsulation of subcutaneous silicone implants in mice. Conventionally stiff silicones (elastic modulus, ~2 MPa) coated with a soft silicone layer (elastic modulus, ~2 kPa) reduced collagen deposition as well as myofibroblast activation without affecting the numbers of macrophages and their polarization states. Instead, fibroblasts around stiff implants exhibited enhanced intracellular stress, increased the recruitment of αv and β1 integrins, and activated TGF-β1 signalling. In vitro, the recruitment of αv integrin to focal adhesions and the activation of β1 integrin and of TGF-β were higher in myofibroblasts grown on latency-associated peptide (LAP)-coated stiff silicones than on soft silicones. Antagonizing αv integrin binding to LAP through the small-molecule inhibitor CWHM-12 suppressed active TGF-β signalling, myofibroblast activation and the fibrotic encapsulation of stiff subcutaneous implants in mice.
| Originalsprog | Engelsk |
|---|---|
| Tidsskrift | Nature Biomedical Engineering |
| Vol/bind | 5 |
| Sider (fra-til) | 1437-1456 |
| DOI | |
| Status | Udgivet - 2021 |
Bibliografisk note
Funding Information:We are very grateful to A. Modarressi (Plastic, Reconstructive and Aesthetic Surgery Division, University Hospitals Geneva, Geneva, Switzerland) for providing expert advice on breast implant materials and medical complications. We thank G. Gabbiani (University of Geneva) for kindly providing the α-SMA antibody, H. Ni (St. Michael’s Hospital, Toronto) for the anti-fibrin antibodies, C.-H. Heldin (University of Uppsala, Sweden) for the LTBP-1 antibody and J. Murphy-Ullrich for providing the LAP expression construct. The FN−/− MEFs were a kind gift from M. Costell (Universitat de València, Spain) and R. Fässler (Max Planck Institute of Biochemistry, Munich, Germany). The col1a1 transgenic mice were provided by D. Brenner (University of California, San Diego). We also thank J. Firmino and D. Rajshankar at the Collaborative Advanced Microscopy Labs of Dentistry (CAMiLoD; Faculty of Dentistry, University of Toronto) and S. Plotnikov (Cell and Systems Biology, University of Toronto) for outstanding help with image acquisition and data analysis. We gratefully acknowledge F. Younesi (Hinz laboratory), F. Sarraf and N. Valiquette (Histology service, Faculty of Dentistry, University of Toronto) and the staff of the Centre for Phenogenomics (Mount Sinai Hospital, Toronto) for excellent technical histology support. The research of B.H. is supported by a foundation grant from the Canadian Institutes of Health Research (375597) and support from the John R. Evans Leaders Fund (grant numbers 36050, 38861 and 38430), as well as innovation funds (Fibrosis Network; grant number 36349) from the Canada Foundation for Innovation (CFI) and Ontario Research Fund (ORF). M.E. is supported by an Ontario Graduate Scholarship (OGS). R.S. is supported by a grant from the Mathematics of Information Technology and Complex Systems (MITACS; IT13623).
Publisher Copyright:
© 2021, The Author(s), under exclusive licence to Springer Nature Limited.