Expression of Endogenous Molecules After Pancreatic Islet Isolation and Culture: Implications for Islet Transplantation

Cellular stress or damage causes expression and release of endogenous molecules, such as damage-associated molecular patterns (DAMPs) molecules, which alert the host of danger by triggering immune responses and activating repair mechanisms. High-mobility group box 1 (HMGB1) released from damaged islets has been shown to be associated with poor islet graft outcome, however, few studies evaluated implication of other endogenous molecules such as calreticulin as categorized DAMPs, and binding immunoglobulin protein (Bip) as categorized resolution-associated molecular patterns (RAMPs). The aim of this study is to investigate expression of these endogenous molecules induced by islet isolation and subsequent culture. Our findings suggest that necrotic process of the cells in central area after islet isolation and subsequent culture leads to express and release of not only DAMPs but also RAMPs, which might be responsible for counterbalance the DAMPs. A better understanding of the biological response to both DAMPs and RAMPs in isolated/cultured islets would improve its efficacy of islet transplantation.