Exp Mol Med.  2012 Jan;44(1):20-25. 10.3858/emm.2012.44.1.001.

Functional improvement of porcine neonatal pancreatic cell clusters via conformal encapsulation using an air-driven encapsulator

• Park SJ
• Shin S
• Koo OJ
• Moon JH
• Jang G
• Ahn C
• Lee BC
• Yoo YJ

• KMID: 1120138
• DOI: http://doi.org/10.3858/emm.2012.44.1.001

Abstract

Transplantation of islet cells into diabetic patients is a promising therapy, provided that the islet cells are able to evade host immune rejection. With improved islet viability, this strategy may effectively reverse diabetes. We applied 2% calcium alginate to generate small and large capsules to encapsulate porcine neonatal pancreatic cell clusters (NPCCs) using an air-driven encapsulator. After encapsulation, the viability was assessed at 1, 4, 7, 14 and 28 days and secretion of functional insulin in response to glucose stimulation were tested at days 14 and 28. Selective permeability of the small alginate capsules was confirmed using various sizes of isothiocyanate-labeled dextran (FITC-dextran). Encapsulation of NPCCs was performed without islet protrusion in the small and large capsules. The viability of NPCCs in all experimental groups was greater than 90% at day 1 and then gradually decreased after day 7. The NPCCs encapsulated in large capsules showed significantly lower viability (79.50 +/- 2.88%) than that of naive NPCCs and NPCCs in small capsule (86.83 +/- 2.32%, 87.67 +/- 2.07%, respectively) at day 7. The viability of naive NPCCs decreased rapidly at day 14 (75.67 +/- 1.75%), whereas the NPCCs encapsulated in small capsules maintained (82.0 +/- 2.19%). After 14 and 28 days NPCCs' function in small capsules (2.67 +/- 0.09 and 2.13 +/- 0.09) was conserved better compared to that of naive NPCCs (2.04 +/- 0.25 and 1.53 +/- 0.32, respectively) and NPCCs in large capsules (2.04 +/- 0.34 and 1.13 +/- 0.10, respectively), as assessed by a stimulation index. The small capsules also demonstrated selective permeability. With this encapsulation technique, small capsules improved the viability and insulin secretion of NPCCs without islet protrusion.

Keyword

alginic acid; diabetes mellitus type 1; insulin-secreting cells; islets of Langerhans transplantation; tissue therapy

MeSH Terms

Alginates/chemistry/metabolism
Animals
Animals, Newborn
Capsules/chemistry
Cell Survival
Diabetes Mellitus/pathology/*therapy
Disease Models, Animal
Glucuronic Acid/chemistry/metabolism
Graft Rejection/etiology/*prevention & control
Hexuronic Acids/chemistry/metabolism
Humans
Insulin/secretion
Islets of Langerhans/*metabolism/pathology
Islets of Langerhans Transplantation/*methods
Postoperative Complications/etiology/*prevention & control
*Swine