Effective removal of alginate-poly-L-lysine microcapsules from pancreatic islets by use of trypsin-EDTA

✍ Scribed by de Groot, Martijn ;Leuvenink, Henri G. D. ;Keizer, Paula P. M. ;Fekken, Susan ;Schuurs, Theo A. ;van Schilfgaarde, Reinout

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 205 KB
• Volume: 67A
• Category: Article
• ISSN: 0021-9304
• DOI: 10.1002/jbm.a.10023

✦ Synopsis

Abstract

Although the transplantation of alginate‐poly‐L‐lysine‐alginate encapsulated islets of Langerhans usually is successful, graft survival is still limited. Molecular analysis by RT‐PCR of the encapsulated islets may provide insight into the mechanisms that affect islets during graft failure. However, RT‐PCR on encapsulated islets is not possible because the poly‐L‐lysine of the capsule interferes with both cDNA synthesis and PCR amplification. We applied a method that mechanically removes the microcapsules from the islets after a short trypsin–EDTA treatment (decapsulation), thereby enabling RT‐PCR analysis. The results of this study show that the decapsulation procedure does not affect islet vitality and has only minor effects on islet function and morphology. The decapsulation does not affect GAPDH, β‐actin, Bcl‐2, or Bax gene expression. This method is an improvement over the time‐consuming manual dissection of microcapsules because it allows for the rapid and relatively harmless removal of capsules on a larger scale. Decapsulation offers the possibility of applying RT‐PCR, as well as other methods, which cannot be performed on encapsulated islets. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 679–683, 2003