EFFECT OF HEAT TRANSFER ON THE EFFICACY OF HYPOTHERMIC COLD STORAGE METHODS

One of the major impediments in clinical pancreatic islet transplantation is the lack of current agreement on optimal conditions for pancreas preservation before islet isolation. To retard cellular metabolism and reduce oxygen consumption, islet cells are typically maintained at a low temperature during preservation. However, cellular ischemic injury that results from such a cold storage method reduces the islet yield and viability and the accompanying chances of a successful transplant. The Two-Layer Method (TLM) of organ preservation, a protocol credited to Kuroda et al. at Kobe University, is reported as effective in preventing the adverse effects of both cold and warm ischemia and in increasing the viability of islet cells. Although it is generally believed that the TLM has superior functional efficacy over other methods (like simple cold storage with either University of Wisconsin (UW) solution or perfluorocarbon (PFC) alone), the fundamental basis for the putative efficacy of TLM still remains unexplained. This study hypothesizes that the TLM conveys salutary cell preservation due to favorable heat transfer between the pancreas tissues and the participating fluids viz. UW solution and PFC. In this work, experimental investigations of the heat transfer mechanism between the fluids and pancreata are studied. Initial experimental data for simple storage in PFC and UW solutions alone have been generated. It is found that there is a 33 % difference in temperature (L'.T) between the two methods at the end of 6 minutes and this L'.Tis found to exist for an extended period of time (till 1.5 hrs). These data provide reference values for in vitro experimentation of the Two-Layer Method