Pretransplant induction of HSP-70 in isolated adult pig islets decreases early islet xenograft survival

D Brandhorst, H P Hammes, H Brandhorst, A Zwolinski, F Nahidi, A Alt, R G Bretzel
Cell Transplantation 2000, 9 (3): 423-30
The heat-induced HSP-70 expression protects rat islet single cells against lysis mediated by nitric oxide (NO), reactive oxygen, and streptozotocin. The present study was performed to investigate the potential antiinflammatory effect of pretransplant heat shock in adult pig islets for subsequent early islet xenograft survival. Maximum HSP-70 expression in freshly isolated pig islets was induced by hyperthermia at 43 degrees C for 90 min prior to islet regeneration at 37 degrees C for 4-6 h. Heat-stressed and sham-treated islets were incubated in 0.6 mM H2O2 or 1.5 mM Na-nitroprusside at 37 degrees C for 20 h. Early graft survival was evaluated in normoglycemic Lewis rats after simultaneous, contralateral transplantation of heat-shocked islets and sham-treated islets into the renal subcapsular space of the same recipient. Prior hyperthermia significantly reduced specific lysis of islets exposed to NO or H2O2, although protection was only marginal. No differences were observed between viability of heat-shocked and sham-treated islets after NO exposure. In contrast, prior heat shock increased islet viability after H2O2 treatment. The finding that hyperthermia reduced recovery of initially grafted pig insulin 48 h after transplantation by 30% compared to controls contrasted significantly with an increased insulin recovery in heat-exposed islets at the end of simultaneous 37 degrees C culture. The observation, that the heat-induced HSP-70 expression decreases early islet xenograft survival as reflected by recovery of grafted insulin, implies an enhancement of islet immunogenicity and the induction of apoptosis. Future experiments aiming at augmentation of intrinsic defense mechanisms should consider detrimental effects associated with induction of heat shock proteins.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"