Beta-5 score to evaluate pig islet graft function in a primate pre-clinical model

Area of Science:

• Endocrinology and Metabolism
• Xenotransplantation Research
• Pre-clinical Diabetes Models

Background:

• Assessing the function of transplanted islets is crucial for diabetes treatment.
• Existing scoring systems need validation in pre-clinical models before human application.

Purpose of the Study:

• To develop and validate a composite scoring system (β5 score) for assessing pig islet function in a primate model.
• To compare the efficacy of the β5 score against established indices like the SUITO index and CP/G ratio.

Main Methods:

• Two established human islet scoring methods (SUITO index, CP/G ratio) and a novel β5 score were evaluated in non-diabetic and streptozotocin-induced diabetic primates.
• The β5 score incorporates fasting blood glucose, glycosuria, polydipsia, and polyuria.
• Scores were correlated with pancreatic β-cell mass and assessed post-transplantation of microencapsulated and macroencapsulated pig islets.

Main Results:

• The CP/G ratio and β5 score showed a strong correlation with pancreatic β-cell mass, unlike the SUITO index.
• The β5 score demonstrated high internal consistency (Cronbach's alpha = 0.97).
• Post-transplantation, both CP/G ratio and β5 score correlated significantly with pig islet xenograft function, diabetes control, and glycosylated hemoglobin levels.

Conclusions:

• The novel β5 score is a valid and accurate tool for assessing islet transplantation outcomes in pre-clinical primate models.
• The β5 score offers a reliable method for evaluating pig islet xenograft functionality and diabetes management.