ABSTRACT
The article "The effect of cationically modified phosphorylcholine polymers on human osteoblasts in vitro and their effect on bone formation in vivo", written by Jonathan M. Lawton, Mariam Habib, Bingkui Ma, Roger A. Brooks, Serena M. Best, Andrew L. Lewis, Neil Rushton and William Bonfield, was originally published Online First without open access. After publication in volume 28, issue 9, page 144 it was noticed that the copyright was wrong in the PDF version of the article. The copyright of the article should read as "
ABSTRACT
The effect of introducing cationic charge into phosphorylcholine (PC)-based polymers has been investigated in this study with a view to using these materials as coatings to improve bone formation and osseointegration at the bone-implant interface. PC-based polymers, which have been used in a variety of medical devices to improve biocompatibility, are associated with low protein adsorption resulting in reduced complement activation, inflammatory response and cell adhesion. However, in some applications, such as orthopaedics, good integration between the implant and bone is needed to allow the distribution of loading stresses and a bioactive response is required. It has previously been shown that the incorporation of cationic charge into PC-based polymers may increase protein adsorption that stimulates subsequent cell adhesion. In this paper, the effect of cationic charge in PC-based polymers on human osteoblasts (HObs) in vitro and the effect of these polymers on bone formation in the rat tibia was assessed. Increasing PC positive surface charge increased HOb cell adhesion and stimulated increased cell differentiation and the production of calcium phosphate deposits. However, when implanted in bone these materials were at best biotolerant, stimulating the production of fibrous tissue and areas of loosely associated matrix (LAM) around the implant. Their development, as formulated in this study, as bone interfacing implant coatings is therefore not warranted.
