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Updated: May 18, 2026
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A Method for Murine Islet Isolation and Subcapsular Kidney Transplantation
Published on: April 13, 2011
Targeting cells causing split tolerance allows fully allogeneic islet survival with minimal conditioning in NOD mixed
D P Al-Adra1, R Pawlick, A M J Shapiro
1Department of Surgery and Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada.
Summary
Researchers overcame split tolerance in islet transplantation by depleting T cells in NOD mice. This generated long-term mixed chimerism, leading to immunocompetent, diabetes-free mice that accept donor islet allografts.
Area of Science:
- Immunology
- Transplantation Biology
- Diabetes Research
Background:
- Mixed chimerism can prevent long-term immunosuppression and chronic rejection in islet transplantation.
- Split tolerance, where some donor tissues are accepted while others are rejected, remains a challenge.
- Previous protocols in NOD mice induced mixed chimerism but resulted in split tolerance.
Purpose of the Study:
- To investigate the mechanisms underlying split tolerance in NOD mice.
- To identify the specific immune cells responsible for split tolerance.
- To develop a refined protocol for achieving full donor-specific tolerance in islet transplantation.
Main Methods:
- Utilized radiation chimeras to study the role of radiosensitive components in NOD mice.
- Analyzed lymphocyte populations (T cells, NK cells, B cells) to determine their role in split tolerance.
- Refined the chimerism induction protocol by incorporating nonmyeloablative recipient NOD T cell depletion.
Main Results:
- Identified that the radiosensitive component of NOD mice plays a significant role in split tolerance.
- Demonstrated that preexisting NOD T cells, not NK or B cells, mediate split tolerance and resist chimerism induction.
- Successfully generated long-term mixed chimerism across fully allogeneic barriers after T cell depletion.
Conclusions:
- Preexisting T cells are a primary barrier to achieving full tolerance in islet transplantation.
- Depletion of recipient T cells is crucial for inducing long-term mixed chimerism and donor-specific tolerance.
- The refined protocol results in immunocompetent, diabetes-free chimeric NOD mice that accept islet allografts, offering a potential alternative to long-term immunosuppression.
