European cells & materials最新文献

Tendons perform a critical function in the musculoskeletal system by integrating muscle with skeleton and enabling force transmission. Damage or degeneration of these tissues lead to impaired structure and function, which often persist despite surgical intervention. While the immune response and inflammation are important drivers of both tendon healing and disease progression, there have been relatively few studies of the diverse immune cell types that may regulate these processes in these tissues. To date, most of the studies have focused on macrophages, but emerging research indicate that other immune cell types may also play a role in tendon healing, either by regulating the immune environment or through direct interactions with resident tenocytes. The present review synthesises the literature on innate and adaptive immune system cells that have been implicated in tendon healing or disease, in the context of animal injury models, human clinical samples or in vitro experiments.

Orthopaedic surgical site infections, especially when a hardware is involved, are associated with biofilm formation. Clinical strategies for biofilm eradication still fall short. The present study used a novel animal model of long-bone fixation with vancomycin- or gentamicin-controlled release and measured the levels of antibiotic achieved at the site of release and in the surrounding tissue. Then, using fluids that contain serum proteins (synovial fluid or diluted serum), the levels of vancomycin or gentamicin required to substantially reduce colonising bacteria were measured in a model representative of either prophylaxis or established biofilms. In the in vivo model, while the levels immediately adjacent to the antibiotic release system were up to 50× the minimal inhibitory concentration in the first 24 h, they rapidly dropped. At peripheral sites, values never reached these levels. In the in vitro experiments, Staphylococcus aureus biofilms formed in serum or in synovial fluid showed a 5-10 fold increase in antibiotic tolerance. Importantly, concentrations required were much higher than those achieved in the local delivery systems. Finally, the study determined that the staged addition of vancomycin and gentamicin was not more efficacious than simultaneous vancomycin and gentamicin administration when using planktonic bacteria. On the other hand, for biofilms, the staged addition seemed more efficacious than adding the antibiotics simultaneously. Overall, data showed that the antibiotics' concentrations near the implant in the animal model fall short of the concentrations required to eradicate biofilms formed in either synovial fluid or serum.

The eCM special issue on Dental Regenerative Biology concentrates on recent key developments that will probably soon lead to significantly improved dental treatments. Progress in the understanding of the biology and technology involved provides exciting new clinical approaches to repairing and regenerating missing or damaged dental tissues. The application of stem cells has the potential to improve tissue regeneration and the use of significantly improved biomaterials can aid dental tissue healing. This editorial highlights the importance of merging the various biological and technological disciplines in order to obtain novel state-of-the-art products and generating new and original clinical concepts.