Study on the levels of CD19＋CD5＋CD1dhigh B10 cells in NOD mice

Abstract

Objective To study the alterations of CD19＋CD5＋CD1dhigh B, Th1 and Th17 cells in non-obese diabetic （ NOD） mice and the correlation between B10 cells and type 1 diabetes in NOD mice. Methods Flow cytometry （ FCM） was used to measure the levels of CD19＋CD5＋CD1dhigh B, CD19＋IL-10＋B, CD4＋IFN-γ＋Th1, CD4＋IL-17＋Th17 and CD4＋CD25＋Foxp3＋T cells in NOD mice （ 4 weeks old NOD mice：group A, n=10;8 weeks old NOD mice：group B, n=10; NOD mice with diabetes： group C, n=10） and age-matched C57BL/6 mice （ control group, n=20 ） .Hematoxylin-eosin staining of pancreatic tissues was performed for histopathological assessment of the development of insulitis in NOD mice.Results （1） Histopathological analysis showed that mice from A, B and C groups respectively showed no insulitis, insulitis and obvious insulitis with no intact islets.（2） The highest levels of B10 cells in NOD mice were ob-served in group B, followed by those in group C and group A （P〈0.01）.No significant differences with the levels of B10 cells were found among different tissues of 4 weeks old NOD mice （P〉0.05）.More B10 cells were detected in pancreatic lymph nodes than in other tissues of 8 weeks old NOD mice, the levels of which were also higher than those in pancreatic lymph nodes of mice form group C （ P〈0.01） .The highest levels of B10 cells were detected in peripheral lymph nodes among all tissues samples collected from NOD mice with diabetes （P〈0.01）.（3） The levels of Th1 and Th17 cells in mice from group C were remarkably in-creased as compared with those in mice from group A and B （P〈0.01）.（4） The percentages of CD4＋CD25＋Foxp3＋T cells in mice from group C showed no differences with those in mice from A and B groups. No significant difference with Treg cells were observed between NOD mice and age-matched C57BL/6 mice （P〉0.05）.Conclusion The percentages and distribution of B10 cells in NOD mice changed with age and the development of insulitis.The decrease of B10 cells might participate in the development of type 1 diabe-tes in NOD mice. Key words: Regulatory B cells Type 1 diabetes Th1 cells Th17 cells Regulatory T cells