Clinical application of microencapsulated islets: Actual prospectives on progress and challenges

In vitro study of partially hydrolyzed poly(2-ethyl-2-oxazolines) as materials for biomedical applications

“…Specifically, water-soluble cationic polymers, such as poly(L-lysine) (PLL), polyethylenimine (PEI), diethylaminoethyl dextran (DEAE-DEX), and polyamidoamine (PAMAM) dendrimers, have been employed in a variety of gene and drug delivery system applications [2,3]. PLL, poly(L-ornithine) and poly(methylene-co-guanidine) (PMCG) have been used for the preparation of polyelectrolyte complexes for cell encapsulation [4][5][6]. Chitosan represents a natural biocompatible cationic polymer recommended for use in a variety of biomedical applications, among them recent reports on drug and gene delivery as well as cell immobilization [7].…”

Transplantable bioartificial pancreas devices: current status and future prospects

“…Numerous studies on islet microencapsulation have been published and reviewed on various rodent diabetes models [35,36]. However, this approach has shown limitations in achieving significance within large animals and human clinical trials [37][38][39][40][41][42][43]. The standard islet encapsulating alginate microcapsules are produced by dropwise addition of sodium alginate, mixed with islets, into a bath of CaCl2 or BaCl2, which rapidly crosslinks to form a hydrogel capsule containing the islet.…”

Treatment of diabetes with encapsulated pig islets: an update on current developments

“…To achieve long-term biocompatibility and viability (e.g. >6 months) and favorable immunoprotection of alginate microencapsulated pig islets in primate recipients, several suggestions should be considered (Sun et al, 1996;Dufrane et al, 2006b;Calafiore and Basta, 2014): (1) the use of donor pigs with a well-defined genetic background; (2) the use of pig islets with high-purity (>90% purity); (3) fabrication of microcapsules using highly purified material with improved stability, low heavy metal, protein and endotoxin content, and a "clinical-grade" basic alginate is recommended; (4) the culture of microencapsulated islets in a medium containing 1.8 mmol/L CaCl 2 for 18 or 24 h prior to implantation; and (5) the transplantation of grafts composed of more than 90% well-shaped capsules (of regular and spherical shape). Elliott et al (2007) first reported a case of long-term survival (>9.5 years) of microencapsulated NPCCs in a male patient with T1DM who received a single implantation of alginate based grafts (15 000 IEQs/kg) into the peritoneal cavity in 1996.…”