Islet isolation assessment in man and large animals

Area of Science:

• * Transplantation Biology
• * Endocrine Research
• * Islet Cell Biology

Background:

• * Advancements in large mammal and human islet isolation necessitate precise assessment techniques.
• * Current methods for evaluating islet yield lack standardization, hindering comparability.
• * Reliable assessment of islet preparations is vital for successful transplantation outcomes.

Purpose of the Study:

• * To discuss quantitative and qualitative criteria for assessing islet isolation.
• * To recommend standardized methods for evaluating islet number, volume, purity, and integrity.
• * To highlight the importance of both in vitro and in vivo functional tests for islet viability.

Main Methods:

• * Dithizone staining for estimating islet number and purity.
• * Morphological assessment for islet identification and integrity.
• * Fluorometric dyes for cell viability assays.
• * Glucose perifusion for dynamic insulin release assessment.
• * In vivo transplantation into diabetic nude rodents as the ultimate viability test.

Main Results:

• * Dithizone staining allows for immediate estimation of islet count and purity.
• * Morphological assessment confirms islet identity and preparation quality.
• * Combined inclusion/exclusion dyes provide simultaneous viability data.
• * Glucose perifusion offers dynamic insulin secretion profiles.
• * In vivo transplantation is the definitive measure of islet function post-transplantation.

Conclusions:

• * Standardized guidelines are essential for consistent islet isolation assessment.
• * A combination of staining, morphological, in vitro, and in vivo tests ensures comprehensive evaluation.
• * These recommendations aim to improve the interpretation and comparison of islet isolation procedures across different research centers.