Improving function and survival of porcine islet xenografts using microencapsulation and culture preconditioning.
OBJECTIVE
Porcine pancreatic islets have been difficult to preserve because isolated porcine islets tend to disaggregate to single cells and lose function under culture conditions. In the current study, the influence of agarose microencapsulation on the maintenance of the number and function of islets in culture preservations and the effect of culture preconditioning of microencapsulated porcine islets on xenogenic transplantation were investigated.


METHODS
Porcine islets were isolated and then microencapsulated in 5% agarose membrane. The percentage of naked and microencapsulated islets remaining in the culture preservations was assessed. The effect of microencapsulation and culture on secretory function was investigated in vitro. The survival of overnight-cultured and 7-days-cultured microencapsulated islets in xenogenic transplantations was examined.


RESULTS
A good percentage of microencapsulated islets remained in the culture preservations. They could maintain good secretory functions in vitro after 7 days of culture. In addition, we observed a significant prolongation of mean islet survival by culture preconditioning.


CONCLUSIONS
The present findings suggest that microencapsulation is one of the useful preserving methods for maintenance of the number and function of cultured isolated porcine islets. Moreover, culture preconditioning is effective for improving islet survival and might be a good option leading to clinical success.
Sato
Hirohide
H
Department of Surgery, Fukui Medical University, Fukui, Japan. hirohide@jc4.so-net.ne.jp
Kobayasi
Taizou
T
Murakami
Makoto
M
Kimura
Toshihisa
T
Yamaguchi
Akio
A
Nakagawara
Gizou
G
Iwata
Hiroo
H
D000818:Animals; D018929:Cell Culture Techniques / Q000379:methods; D002478:Cells, Cultured; D006085:Graft Survival; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology / Q000378:metabolism; D016381:Islets of Langerhans Transplantation / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D012685:Sepharose / Q000737:chemistry; D013552:Swine; D014021:Tissue Preservation / Q000379:methods*; D014183:Transplantation, Heterologous / Q000473:pathology
D007328:Insulin; D012685:Sepharose