Bridging the gap between in vitro and in vivo evaluation of biomaterials- associated infections

PhD ceremony: Mr. G. Subbiahdoss, 13.15 uur, Academiegebouw, Broerstraat 5, Groningen

Thesis: Bridging the gap between in vitro and in vivo evaluation of biomaterials- associated infections

Promotor(s): prof. H.C. van der Mei, prof. H.J. Busscher

Faculty: Medical Sciences

Biomaterials play an important role in modern medicine in the restoration of tissue, organ or body function. The use of biomaterial implants and medical devices is mainly restricted by complications due to biomaterial-associated infections (BAI). There are various routes along which microorganisms can enter the body and develop a BAI in the case of permanent implants. The best-documented route is direct contamination of an implant during surgery (peri-operative contamination). BAI can also be initiated immediately post-surgery during hospitalization (post-operative contamination) or microbial spreading through blood from infections elsewhere in the human body.

In 1987, the orthopedic surgeon Anthony Gristina coined the term “race for the surface” that is the fate of a biomaterial implant was depicted as a race between microbial adhesion and biofilm growth on an implant surface versus tissue integration. Irrespective of the route of infection, the fate of biomaterial implants depends mainly on the outcome of the so-called ‘race for the surface’.

Till today, biomaterials or functional coatings were evaluated in vitro either for their ability to resist bacterial adhesion or for their ability to support mammalian cell adhesion and proliferation based on the concept of the race for the surface. However, no attempt was made to address the simultaneous effects of the presence of bacteria and mammalian cells on a biomaterial surface due to the lack of proper methodology, which according to the concept of the ‘race for the biomaterial surface’, is crucial for the ultimate fate of a biomaterial implant. A proper method to study the race for the surface on an experimental basis, would constitute a valuable bridge between in vivo and in vitro studies. Therefore, this thesis focuses on the development of methods that could bridge the gap between in vitro and in vivo studies on BAI.