Format

Send to

Choose Destination
Transplantation. 2006 May 15;81(9):1345-53.

Six-month survival of microencapsulated pig islets and alginate biocompatibility in primates: proof of concept.

Author information

1
Laboratory of Experimental Surgery, Université catholique de Louvain, Faculté de Médecine, and Department of Pathology, Cliniques Universitaires Saint-Luc, Brussels, Belgium.

Abstract

BACKGROUND:

Pig islets xenotransplantation remains associated with a strong humoral and cellular xenogeneic immune responses. The aim of this study was to assess the long-term biocompatibility of alginate encapsulated pig islets after transplantation in primates.

METHODS:

Adult pig islets encapsulated in alginate under optimal conditions (n=7) or not (n=5) were transplanted under the kidney capsule of nondiabetic Cynomolgus maccacus. Additional primates received empty capsules (n=1) and nonencapsulated pig islets (n=2) as controls. Capsule integrity, cellular overgrowth, pig islet survival, porcine C-peptide and anti-pig IgM/IgG antibodies were examined up to 6 months after implantation.

RESULTS:

Nonencapsulated islets and islets encapsulated in nonoptimal capsules were rapidly destroyed. In seven primates receiving perfectly encapsulated pig islets, part of the islets survived up to 6 months after implantation without immunosuppression. Porcine C-peptide was detected after 1 month in 71% of the animals. The majority of grafts (86%) were intact and completely free of cellular overgrowth or capsule fibrosis. Explanted capsules, after 135 (n=2/2) and 180 (n=2/3) days, demonstrated residual insulin content and responses to glucose challenge (stimulation index of 2.2). Partial islet survival was obtained despite an elicited anti-pig IgG humoral response.

CONCLUSIONS:

Optimal alginate encapsulation significantly prolonged adult pig islet survival into primates for up to 6 months, even in the presence of antibody response.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wolters Kluwer
Loading ...
Support Center