Prolonged Islet Allograft Survival Time In NOD Mice By Combining With Two Different Antigen-specific Regulatory T Cells Injection

【Objective】The aim of this study was to demonstrate the effects on prolonging survivaltime of islet allograft in NOD mice by combining with two different antigen-specificregulatory T cells injection.【Methods】Immature dendritic cells from C57BL/6mice induced na ve T cells of NODmice into donor antigen-specific regulatory T cells; GAD-65antigen pulsed immaturedendritic cells from NOD mice induced na ve T cells of NOD mice into islet antigen-specific regulatory T cells. Antigen-specific regulatory T cells were infused into NODmice with recent onset type1diabetes, then they received islet allograft from C57BL/6mice. Graft survival time was assessed by daily blood glucose levels. Animals in thisstudy were divided into5groups: group1,Control group: NOD mice were without anytreatment;group2, Simple islet transplant group: NOD mice received islet allograftwithout regulatory T cells injection; group3,NOD mice were injected with donorantigen-specific regulatory T cells, then underwent islet transplantation;group4,NOD mice were injected with islet antigen-specific regulatory T cells, then underwentislet transplantation;group5, NOD mice were injected with two different antigen-specificregulatory T cells, then underwent islet transplantation. Daily blood glucose levels of themice in this experiment should be recorded since the day after the transplantation. 【Results】Blood glucose levels were sustained above11.1mmol/L in Control group(n=5); the survival time of islet allograft in the NOD mice in group1were between days8and16(mean12.4±3.21d; n=5); in group2were between days19and31(mean24.8±4.49d; n=5); in group3were between days21and37(mean30.4±6.47d; n=5);and in group4were between days39and59(mean47.4±7.89d; n=5), which weresignificantly prolonged compared to other groups (P<0.05).【Conclusions】 Combining with two different antigen-specific regulatory T cellsinjection significantly prolonged survival of islet allograft in NOD mice with recentonset type1diabetes as recipients.