Upregulating CD4+CD25+FOXP3+ regulatory T cells in pancreatic lymph nodes in diabetic NOD mice by adjuvant immunotherapy.
BACKGROUND
Immunotherapy with Complete Freund's adjuvant (CFA) is effective in ameliorating autoimmunity in diabetic nonobese diabetic (NOD) mice. We investigated whether CFA treatment up-regulates CD4+CD25+Foxp3+ regulatory T cells and increases transforming growth factor (TGF)-beta1 production in diabetic NOD mice.


METHODS
New-onset diabetic NOD mice were treated with CFA and exendin-4, a potent analog of glucagon-like peptide-1. Reversal of diabetes was determined by monitoring blood glucose level. Ameliorating autoimmunity through immunoregulation was assessed by adoptive transfer. Regulatory T cells in the peripheral blood, spleen, thymus, and pancreatic nodes were measured. TGF-beta1 in plasma and the insulin content in the pancreas were also measured. Immunostainings for insulin and BrdU were performed.


RESULTS
New-onset diabetes could be reversed in 38% of NOD mice treated with CFA alone and in 86% of NOD mice treated with both CFA and exendin-4. Diabetes adoptive transfer by splenocytes from CFA-treated NOD mice was delayed. The percentage of CD4+CD25+Foxp3+ regulatory T cells in the pancreatic lymph nodes of CFA-treated NOD mice was significantly increased at 1, 5, and 15 to 17 weeks after treatment. TGF-beta1 in the plasma of CFA-treated NOD mice was also significantly increased. Combining CFA with exendin-4 treatment significantly increased the insulin content and the numbers of insulin and BrdU double-labeled beta cells in the islets.


CONCLUSIONS
Our results demonstrated that CFA treatment ameliorates autoimmunity in diabetic NOD mice by up-regulating CD4=CD25+Foxp3+ regulatory T cells and increasing TGF-beta1 production. Exendin-4 enhanced the effect of CFA on reversing diabetes in NOD mice by stimulating beta-cell replication.
Tian
Bole
B
Department of Surgery and Diabetes Institute for Immunology and Transplantation, University of Minnesota, Minneapolis, MN 55455, USA.
Hao
Jianqiang
J
Zhang
Yu
Y
Tian
Lei
L
Yi
Huimin
H
O'Brien
Timothy D
TD
Sutherland
David E R
DE
Hering
Bernhard J
BJ
Guo
Zhiguang
Z
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D019264:Adoptive Transfer; D000818:Animals; D015551:Autoimmunity / Q000187:drug effects; D001786:Blood Glucose / Q000187:drug effects; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology / Q000637:transplantation; D049109:Cell Proliferation / Q000187:drug effects; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy* / Q000276:immunology; D004195:Disease Models, Animal; D004359:Drug Therapy, Combination; D000077270:Exenatide; D005260:Female; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D005620:Freund's Adjuvant / Q000494:pharmacology; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000378:metabolism; D050417:Insulin-Secreting Cells / Q000187:drug effects / Q000276:immunology; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism*; D008198:Lymph Nodes / Q000187:drug effects* / Q000276:immunology; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D010179:Pancreas / Q000187:drug effects* / Q000276:immunology; D010455:Peptides / Q000494:pharmacology; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects* / Q000276:immunology / Q000637:transplantation; D013997:Time Factors; D053773:Transforming Growth Factor beta1 / Q000097:blood; D015854:Up-Regulation; D014688:Venoms / Q000494:pharmacology
D000276:Adjuvants, Immunologic; D001786:Blood Glucose; D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D007004:Hypoglycemic Agents; C508018:Il2ra protein, mouse; D007328:Insulin; D053645:Interleukin-2 Receptor alpha Subunit; D010455:Peptides; D053773:Transforming Growth Factor beta1; D014688:Venoms; D005620:Freund's Adjuvant; D000077270:Exenatide