A Novel Method to Isolate Islet Cells

DESCRIPTION (provided by applicant): The goals for this Phase I proposal are: 1) construction and bench testing of a novel device to dissociate tissue from donor pancreas using ultrasound for the recovery of pancreatic islet cells for transplantation, and 2) marked improvement in yields and viability of islets recovered using this approach as compared to the existing, standard method. Pancreatic islet cell transplantation has received considerable attention as a procedure with the potential to cure patients with diabetes. Allergenic transplantation as a potential cure for type 1 diabetes has been shown to be a realistic approach with several centers reporting insulin independence, or substantial improvement in patients who suffered from type I diabetes. In addition, auto-islet transplantation for persons undergoing pancreatectomy for chronic pancreatitis has been performed with increasing success. Despite these encouraging reports, several obstacles remain that prevent the widespread adoption of the application, including: The high level of skill required by those involved in the donor cell isolation and purification process. The lack of a clear understanding of the manner in which specific parameters of the isolation and purification process interact to affect outcomes and the inability to control these parameter, resulting in islet recovery rates at approximately 55 - 60% of viable cells. The severe shortage of donor organs. The need for long term immunosuppression and the deleterious effects of these drugs on long term islet cell function. The deterioration of graft function with time from islet exhaustion due to the transplantation of insufficient beta cell mass. It is our hypothesis that the current method of mechanical shaker agitation to dissociate pancreatic tissue is deleterious to optimum isolation results due to: 1) the need for a heat exchanger that results in a large thermal latency which exposes the cells to continued harmful enzymatic action while the system is cooled, 2) the inability of the shaker to dissociate the pancreas uniformly, and 3) the use of marbles to break apart the pancreas which results in physical damage at the cellular level. Advanced Biological Technologies, in collaboration with the University of Cincinnati, is developing a process to positively impact these obstacles through a novel use of ultrasonic technology. The system we describe herein is designed to fully exploit the spatial, temporal and thermal engineering parameters necessary to dissociate pancreatic tissue, thereby maximizing cell yield and viability in a consistent and repeatable manner while eliminating the need for a skilled operator. The objectives for the Phase I feasibility study are: Aim 1. Design and fabrication of sonic tissue dissociation system for the recovery of islets of Langerhans. Aim 2. Identify and assess initial performance profile that will be utilized for device optimization. Aim 3. Compare novel sonic approach to current islet cell dissociation method. Our team has more than 2 decades experience in device fabrication and testing for the isolation and perfusion of cells for research and transplantation and a clinical islet transplantation program with 75 patients transplanted in a five year period. Project Summary Successful application of this project would impact the quality and quantity of islet cells for transplantation into type I diabetics and for patients transplanted with islets to treat severe chronic pancreatitis. Specifically, the goal is to achieve insulin independence following a single islet infusion instead of the 2 - 3 donor pancreas per recipient currently needed in allergenic transplantation, thus allowing for more patients to receive this treatment. Additionally, and of no less importance, the integration of this technology with ABT's automated isolation device could be used to produce high quality islets for research purposes ensuring high quality islets on a consistent basis. Hence, the dissociation device is an enabling technology that would make it possible for hospitals, universities and companies involved with islet cell research to consistently obtain high quality islet cells for their work.