Immobilization of soluble complement receptor 1 on islets

Nguyen M Luan1, Yuji Teramura, Hiroo Iwata

  • 1Department of Reparative Materials, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-Ku, Kyoto, Japan.

Biomaterials
|April 5, 2011
PubMed

Transplantation of pancreatic islets of Langerhans (islets) is a promising method to treat insulin-dependent diabetes mellitus. Control of complement activation is necessary to improve graft survival in alloislet and xenoislet transplantation. In this study, human soluble complement receptor 1 (sCR1) was immobilized on the islet cell surface through poly(ethylene glycol)-conjugated phospholipid (PEG-lipid) without loss of islet cell viability or insulin secretion ability. sCR1 on islets effectively inhibits complement activation and protects islets against attack by xenoreactive antibodies and complement. This method will be an efficient means to control early islet loss in clinical islet transplantation and realize xenoislet transplantation in the future.

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