Thursday, September 17, 2026 | 11 AM EST
Presented by
Appakalai N, Balamurugan, PhD
Determining the minimal effective collagenase and protease dose is critical to achieve optimal pancreatic digestion while avoiding the detrimental effects of enzyme overdigestion. My earlier work to improve the recovery of functional human islets showed that enzyme mixtures containing intact class I (C1) and class II (C2) C. histolyticum collagenase and an appropriate neutral protease (NB Protease) gave the highest islet yields compared with seven other collagenase-protease enzyme mixtures.(1) A later report showed that BP Protease was as effective as NB Protease for human islet isolation.(2)
The collagenase doses used in the islet isolation above did not assess the effect of different doses of C1 and C2 collagenase activity on human islet yields. A collaborative study with VitaCyte addressed this gap by assessing the effectiveness of four recombinant C1 (rC1) and C2 (rC2) mixtures, combined with a fixed dose of BP Protease, to recover islets from human pancreata. All four enzyme mixtures gave islet yields ≥ 4900 IEQ/g tissue using doses that ranged from 48 to 85% of the standard dose [20 Wunsch U/g tissue (20 WU/g)] of natural purified collagenase (100% = 4.4 mg/g tissue).(2) In a further study, my laboratory evaluated the performance of the lowest dose (2.1 mg/g tissue, 30:70 rC1:rC2 ratio) used in the study above and compared the effectiveness of this collagenase mixture with natural purified collagenase (Collagenase HA).(3) All collagenase-protease mixtures used a fixed dose of BP Protease. These data showed that the rC1-rC2 at 12 WU/g was as effective as the standard dose of Collagenase HA at 20 WU/g. However, when the Collagenase HA dose was reduced to 12 WU/g, the islet yields were ≈ 50% of those obtained with the recombinant collagenase. This webinar will review these and other results from this study.
References
- Balamurugan AN, et al. Transplant (2012) 15:693-702.
- Balamurugan AN, et al. Transplant Direct (2015) 2:e54. doi: 10.1097/TXD.0000000000000563.
- Loganathan G, et al. Am J Transplant (2018) 18:478-485.
Meet the Presenter
Appakalai N, Balamurugan, PhD
Professor of Pediatric Endocrinology
Wendy Novak Diabetes Institute
University of Louisville, Norton Healthcare
Louisville, KY, 40202, USA
As an “isletologist” for the past 30 years, Dr. Balamurugan’s research career has focused on advancing pancreatic islet cell isolation and transplantation for the treatment of type-I diabetes and surgery induced diabetes. He is an international pioneer in islet cell isolation and transplantation and established advanced islet manufacturing protocols for clinical auto-, allo- and xeno-islet transplantations and processed over 2000 human pancreases for clinical transplantation, and islet biology research initiatives. He has performed more than 1000 porcine islet cell isolations and utilized for various xenotransplantation studies. He has published more than 250 research articles including book chapters and serves on the editorial review boards of several journals. He has been invited nationally and internationally to give numerous presentations on his research studies.