Immobilization of anticoagulant-loaded liposomes on cell surfaces by DNA hybridization

Department of Reparative Materials, Institute for Frontier Medical Sciences, Kyoto University, 53 Kawara-Cho, Shogoin, Sakyo-Ku, Kyoto 606-8507, Japan.
Biomaterials (Impact Factor: 8.56). 11/2011; 32(31):7971-7. DOI: 10.1016/j.biomaterials.2011.07.002
Source: PubMed


An unresolved obstacle in transplantation of islets of Langerhans is the early graft loss caused by thrombotic reactions on the surface of islets after intraportal transplantation. We investigated a versatile method for modifying the surface of islets with liposomes carrying the anticoagulant argatroban using an amphiphilic poly(ethylene glycol)-phospholipid conjugate derivative (PEG-lipid) and DNA hybridization. Argatroban was gradually released from the liposomes on the islets, and antithrombic activity was detected in culture medium. Modified islets retained the ability to control insulin release in response to glucose concentration changes. Although we mainly examined surface modification of islets, this technique may be useful for immobilizing various types of small molecules on cells and tissues and thus may have many applications in cell therapy and regenerative medicine.

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    • "Furthermore, studies have demonstrated that derivatives of the PEG-lipids can be used to modify cellular surface [11]. Recently, Iwata et al. [11] [12] developed technologies to immobilize bioactive substances, such enzymes [13], low-molecular weight drugs [14], and even living cells on the surface of pancreatic islets using PEG-lipids [15]. The PEG-lipids provided an ultra-thin coating on the cell surface of pancreatic islet cells, and demonstrated the suppression of IBMIR in two islet transplantation studies [16] [17]. "
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