Mussel Adhesive Protein as a Promising Alternative to Fibrin for Scaffold Fixation during Cartilage Repair Surgery

Abstract

Objective: Fibrin has been used as a standard material for scaffold fixation during cartilage repair surgery. Most of the commercially available fibrin preparations need an additional method for scaffold fixation, most often with sutures, thus damaging the surrounding healthy cartilage. There is therefore a need to find alternatives to this method. In our study, we have investigated the potential possibility to use mussel adhesive protein as such an alternative. Methods: In this study, hydrophobic plastic was coated with the mussel adhesive protein Mefp-1 as well as with other cell adhesives (poly-lysine, fibronectin, and collagen). Human keratinocytes and chondrocytes were seeded on these substrates at 37°C in culture medium, followed by analysis of attachment and proliferation by crystal violet staining and metabolic labelling. Performance of Mefp-1 and fibrin as tissue glues were estimated by tensional force resistance measurement of moist porcine dermis (as a correlate to scaffold) glued to dermis, cartilage, or bone at 37°C. Results: Mefp-1 supported maximal cell attachment at a coating density of approximately 1 µg/cm2. This was at least as good as the other adhesives tested. In addition, it supported cell proliferation at least as good as regular tissue culture plastic over a 7-day period. Measurement of tensional force resistance showed that Mefp-1 performed equally well as fibrin when porcine dermis was glued to cartilage and bone at the same concentration. Separation of the moist tissues after 15-minute incubation required a force of approximately 1 N/cm2 for both compounds. Conclusions: Mefp-1 show properties that qualify it as a compound that potentially could replace fibrin as a tissue glue for scaffold fixation. Given the possibilities to modify this protein by bioengineering, it is likely that the properties can be further improved.