Prevention of core cell damage in isolated islets of Langerhans by low temperature preconditioning.
OBJECTIVE
To study the core cell damage in isolated islets of Langerhans and its prevention by low temperature preconditioning (26 degrees).


METHODS
Islets were cultured at 37 degrees for 7-14 d after isolation, and then at 26 degrees for 2, 4 and 7 d before additional culture at 37 degrees for another 7 d. Core cell damage in the isolated islets was monitored by video-microscopy and analyzed quantitatively by use of a computer-assisted image analysis system. The analysis included daily measurement of the diameter and the area of the isolated islets and the area of the core cell damage that developed in those islets over time during culture. Histology and TdT-mediated dUTP-biotin nick end labeling (TUNEL) assay were used to characterize the cell damage and to monitor islet function.


RESULTS
Microscopic analysis showed that during the 7 to 14 d of culture at 37 degrees, core cell damage occurred in the larger islets with diameters >200 microm, which included both necrotic and apoptotic cell death. Low temperature (26 degrees) culture could prevent core cell damage of isolated islets. The 7-d culture procedure at 26 degrees could inhibit most of the core cell (excluding diameters >300 microm) damages when the islets were re-warmed at 37 degrees.


CONCLUSIONS
Our results indicate that core cell damage within isolated islets of Langerhans correlates with the size of islets. Low temperature (26 degrees) culture can prevent core cell damage in isolated islets, and successfully precondition these islets for incubation at 37 degrees. These novel findings may help to understand the pathophysiology of early loss of islet tissue after transplantation, and may provide a new strategy to improve graft function in the clinical setting of islet transplantation.
Cui
Yun-Fu
YF
Department of General Surgery, the Second Affiliated Hospital, Harbin Medical University, No. 246 Xuefu Street, Nangang District, Harbin 150086, Heilongjiang Province, China. yfcui777@hotmail.com
Ma
Ming
M
Wang
Gui-Yu
GY
Han
De-En
DE
Vollmar
Brigitte
B
Menger
Michael D
MD
D000818:Animals; D002470:Cell Survival; D002478:Cells, Cultured; D003080:Cold Temperature; D006224:Cricetinae; D015925:Cryopreservation; D020287:In Situ Nick-End Labeling; D007515:Islets of Langerhans / Q000473:pathology*; D016381:Islets of Langerhans Transplantation; D008647:Mesocricetus; D019172:Transplantation Conditioning / Q000379:methods*