Biomaterials implant surfaces in the human body are prone to infection. These can develop through three distinctly different infection routes, each with its own unique cell/material/infection interface. Since a biomaterial-associated infection (BAI) is difficult to treat with antibiotics due to the protection offered by the biofilm mode of growth and intra-cellular sheltering of microorganisms, the fate of an infected implant often is removal, at great discomfort to the patient and costs to the healthcare system.
Frequently even, the condition of a patient does not allow replacement surgery or removal of the implant or device. BAI can even be lethal when bacterial spreading throughout the body occurs (sepsis). Whereas the infection rate of primary implants may be considered low (4-6% on average, depending on the implant type), infection rates in revision surgery are much higher (~15%) with huge discomfort to the patients and much higher costs than of primary placement. Furthermore, many implants are used in society translating the ‘low’ BAI percentages into large absolute numbers of patients worldwide. Treatment involves the use of antimicrobials, but antimicrobial resistance is developing faster than new antimicrobials are developed, and the number of effective antimicrobials may reach a critical mass within this century.
The Man, Biomaterials and Microbes (MBM) programme merges the fundamental research on biofilm, the development of biomaterial coatings, infection and antimicrobial resistance, while being closely linked to the clinic for translation of promising materials. The programme works closely with NANOBIOMAT (another programme of the KOLFF Institute) and the Zernike Institute for Advanced Materials, along with other industrial and academic partners.
Although mechanisms of bacterial and mammalian cell adhesion have been studied for decades, no ubiquitously accepted mechanism has been forwarded, and research is ongoing. An important general conclusion is, however, that bacteria often use the same adhesive sites in adsorbed protein layers on biomaterials implants and devices, as do mammalian cells. In order to put mammalian cells at an advantage we need a shift in biomaterial coatings from mono-functional (only non-adhesive to bacteria OR only adhesive to cells) to multi-functional (non-adhesive to bacteria AND adhesive to mammalian cells) ones.
New insights in mechanisms of microbial and mammalian cell adhesion will be applied to develop multi-functional biomaterials coatings. Promising coatings can be translated to clinically-relevant experiments en route to clinical translation. Additionally, the mechanisms of transition of adhered bacteria to the biofilm state, and the development of antimicrobial resistance will translate into new (antibiotic-less) treatments that are less prone to resistance development.
Importantly, methods to evaluate biomaterials coatings are being developed to accommodate multi-functional coatings that require methods by which mammalian cell interaction on a biomaterial can be evaluated simultaneously with biofilm formation and preferably also with the reaction of immune components.
Such studies not only attempt to find solutions for the current problem of BAI, but also prepare for the future problem of infections related to porous, biodegradable scaffold materials as used in tissue engineering.