Authors Bünger, C.M. ; Gerlach, C. ; Freier, T. ; Schmitz, K. P. ; Pilz, M. ; Werner, C. ; Jonas, L. ; Scharack, W. ; Hopt, U.T. ; de Vos, P.
Title Biocompatibility and surface structure of chemically modified immunoisolating alginate-PLL capsules
Date 11.12.2003
Number 11940
Abstract Grafting of encapsulated living cells has the potential to cure a wide variety of diseases. Large-scale application of the technique, however, is hampered by insufficient biocompatibility of the capsules. A major factor in the biocompatibility of capsules is inadequate covering of the inflammatory poly-<FONTSIZE="-1">L</FONT>-lysine (PLL) on the capsules' surface. In the present study, we investigate whether tissue responses against alginate-PLL capsules can be reduced by crosslinking the surface of the capsules with heparin or polyacrylic acid. Our transplant study in rats shows a tissue response composed of fibroblasts and macrophages on alginate-PLL-alginate and alginate-PLL-heparin capsules that was completely absent on alginate-PLL-polyacrylic acid capsules. Atomic force microscopy analyses of the capsules demonstrates that the improv<br />ed biocompatibility of alginate-PLL-capsules by polyacrylic acid coating should not only be explained by a more adequate binding of PLL but also by the induction of a smoother surface. This study shows for the first time that biologic responses against capsules can be successfully deleted by chemically crosslinking biocompatible molecules on the surface of alginate-PLL capsules. &copy; 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 1219-1227, 2003
Publisher Journal of Biomedical Materials Research
Citation Journal of Biomedical Materials Research 67A (2003) 1219-1227

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