101
|
Pearl-Yafe M, Iskovich S, Kaminitz A, Stein J, Yaniv I, Askenasy N. Does physiological β cell turnover initiate autoimmune diabetes in the regional lymph nodes? Autoimmun Rev 2006; 5:338-43. [PMID: 16782559 DOI: 10.1016/j.autrev.2006.02.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2006] [Accepted: 04/04/2006] [Indexed: 10/24/2022]
Abstract
The initial immune process that triggers autoimmune beta cell destruction in type 1 diabetes is not fully understood. In early infancy there is an increased beta cell turnover. Recurrent exposure of tissue-specific antigens could lead to primary sensitization of immune cells in the draining lymph nodes of the pancreas. An initial immune injury to the beta cells can be inflicted by several cell types, primarily macrophages and T cells. Subsequently, infiltrating macrophages transfer antigens exposed by apoptotic beta cells to the draining lymph nodes, where antigen presenting cells process and amplify a secondary immune reaction. Antigen presenting cells evolve as dual players in the activation and suppression of the autoimmune reaction in the draining lymph nodes. We propose a scenario where destructive insulitis is caused by recurrent exposure of specific antigens due to the physiological turnover of beta cells. This sensitization initiates the evolution of reactive clones that remain silent in the regional lymph nodes, where they succeed to evade regulatory clonal deletion.
Collapse
Affiliation(s)
- Michal Pearl-Yafe
- Frankel Laboratory, Center for Stem Cell Research, Schneider Children's Medical Center of Israel, Israel
| | | | | | | | | | | |
Collapse
|
102
|
Siggs OM, Makaroff LE, Liston A. The why and how of thymocyte negative selection. Curr Opin Immunol 2006; 18:175-83. [PMID: 16459069 DOI: 10.1016/j.coi.2006.01.001] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2005] [Accepted: 01/24/2006] [Indexed: 01/18/2023]
Abstract
The generation of T cell receptor (TCR) sequence diversity is the strength of adaptive immunity, yet is also the Achilles' heel. To purge highly self-reactive T cells from the immune system, generation of diversity has coevolved with a mechanism of negative selection. Recent studies have revealed new insights addressing the why and how of negative selection by examining situations in which negative selection has failed in human and animals models of autoimmunity. Both thymocyte extrinsic and intrinsic mechanisms are required to restrict the TCR repertoire to a non-autoreactive set. Negative selection also ensures that T cells emerge with receptors that are focussed on the peptide moiety of MHC-peptide complexes.
Collapse
Affiliation(s)
- Owen Marc Siggs
- John Curtin School of Medical Research and School of Biochemistry and Molecular Biology, The Australian National University, Canberra 2601, Australia
| | | | | |
Collapse
|
103
|
Casu A, Trucco M, Pietropaolo M. A look to the future: prediction, prevention, and cure including islet transplantation and stem cell therapy. Pediatr Clin North Am 2005; 52:1779-804. [PMID: 16301093 DOI: 10.1016/j.pcl.2005.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Type 1 diabetes mellitus (T1DM) is characterized by the almost complete absence of insulin secretion, which is secondary to an autoimmune destruction or dysfunction of the insulin-producing cells of the pancreatic islets of Langerhans. Because T1DM is an autoimmune disease with a long preclinical course, the predictive testing of individuals before the clinical onset of the disease has provided a real opportunity for the identification of risk markers and the design of therapeutic intervention. With such a high degree of predictability using a combination of immunologic markers, strategies to prevent T1DM may become possible. A number of novel therapeutic strategies are under investigation in newly diagnosed T1DM patients and might ultimately be applied to prevent T1DM.
Collapse
Affiliation(s)
- Anna Casu
- Division of Immunogenetics, Department of Pediatrics, Rangos Research Center, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, 3460 Fifth Avenue, Pittsburgh, PA 15213, USA
| | | | | |
Collapse
|
104
|
Bruder D, Westendorf AM, Hansen W, Prettin S, Gruber AD, Qian Y, von Boehmer H, Mahnke K, Buer J. On the edge of autoimmunity: T-cell stimulation by steady-state dendritic cells prevents autoimmune diabetes. Diabetes 2005; 54:3395-401. [PMID: 16306354 DOI: 10.2337/diabetes.54.12.3395] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Targeting of antigens to immature dendritic cells has been shown to result in antigen-specific T-cell tolerance in vivo. In the INS-HA/TCR-HA transgenic mouse model for type 1 diabetes, we tested the potential of the dendritic cell-specific monoclonal antibody DEC-205 conjugated to the hemagglutinin (HA) antigen (DEC-HA) to prevent disease onset. Whereas untreated INS-HA/TCR-HA mice all develop insulitis, and approximately 40% of these mice become diabetic, repeated injection of newborn mice with DEC-HA protected almost all mice from disease development. Histological examination of the pancreata revealed significant reduction of peri-islet infiltrations in DEC-HA-treated mice, and the islet structure remained intact. Moreover, HA-specific CD4+ T-cells from anti-DEC-HA-treated INS-HA/TCR-HA mice exhibited increased expression of Foxp3, cytotoxic T-lymphocyte-associated antigen-4, and the immunosuppressive cytokines interleukin-10 and transforming growth factor-beta. The findings indicate that targeting of the HA antigen to immature dendritic cells in vivo leads to a relative increase of antigen-specific Foxp3+ regulatory T-cells that suppress the development of type 1 diabetes. Our results provide a basis for the development of novel strategies focusing on prevention rather than treatment of autoimmune diseases.
Collapse
Affiliation(s)
- Dunja Bruder
- Department of Mucosal Immunity, German Research Centre for Biotechnology, Mascheroder Weg 1, D-38124 Braunschweig, Germany.
| | | | | | | | | | | | | | | | | |
Collapse
|
105
|
Nakayama M, Babaya N, Miao D, Sikora K, Elliott JF, Eisenbarth GS. Thymic expression of mutated B16:A preproinsulin messenger RNA does not reverse acceleration of NOD diabetes associated with insulin 2 (thymic expressed insulin) knockout. J Autoimmun 2005; 25:193-8. [PMID: 16289958 DOI: 10.1016/j.jaut.2005.09.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2005] [Revised: 07/22/2005] [Accepted: 09/07/2005] [Indexed: 10/25/2022]
Abstract
We detected insulin2 mRNA but not insulin1 in thymus using real-time PCR analysis. Transgenic expression of a mutated insulin message (alanine rather than tyrosine at insulin B chain amino acid 16) was variably induced in thymus of four transgenic founder strains. The transgenic message levels were as high or higher than native insulin2 message. Lack of the insulin2 gene resulted in the enhancement of anti-insulin autoantibodies (regular NOD vs insulin2-knockout NOD, P<0.001) and in the presence of the B16:A insulin transgenes, levels of insulin autoantibodies remained elevated (regular NOD vs insulin2-knockout NOD with B16:A insulin, P<0.01). Diabetes acceleration by the knockout of the insulin2 gene was not influenced by the presence of the B16:A insulin transgenes. These data suggest that the B16:A insulin does not compensate for lack of native insulin expression in thymus. If lack of thymic insulin message of the insulin2 knockout is the cause of diabetes acceleration, this suggests that native insulin B:9-23 sequences may be crucial in thymus for insulin mediated immunomodulation. Further experiments varying native insulin message expression in thymus is necessary for direct comparison, but the current study provides additional evidence of the potential important role of a specific insulin B chain epitope.
Collapse
Affiliation(s)
- M Nakayama
- Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Mail stop B-140, P.O. Box 6511, Aurora, CO 80045, USA
| | | | | | | | | | | |
Collapse
|
106
|
Hassainya Y, Garcia-Pons F, Kratzer R, Lindo V, Greer F, Lemonnier FA, Niedermann G, van Endert PM. Identification of naturally processed HLA-A2--restricted proinsulin epitopes by reverse immunology. Diabetes 2005; 54:2053-9. [PMID: 15983206 DOI: 10.2337/diabetes.54.7.2053] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Type 1 diabetes is thought to result from the destruction of beta-cells by autoantigen-specific T-cells. Observations in the NOD mouse model suggest that CD8+ cytotoxic T-cells play an essential role in both the initial triggering of insulitis and its destructive phase. However, little is known about the epitopes derived from human beta-cell autoantigens and presented by HLA class I molecules. We used a novel reverse immunology approach to identify HLA-A2-restricted, naturally processed epitopes derived from proinsulin, an autoantigen likely to play an important role in the pathogenesis of type 1 diabetes. Recombinant human proinsulin was digested with purified proteasome complexes to establish an inventory of potential COOH-terminals of HLA class I-presented epitopes. Cleavage data were then combined with epitope predictions based on the SYFPEITHI and BIMAS algorithms to select 10 candidate epitopes; 7 of these, including 3 with a sequence identical to murine proinsulin, were immunogenic in HLA-A2 transgenic mice. Moreover, six of six tested peptides were processed and presented by proinsulin-expressing cells. These results demonstrate the power of reverse immunology approaches. Moreover, the novel epitopes may be of significant interest in monitoring autoreactive T-cells in type 1 diabetes.
Collapse
Affiliation(s)
- Yousra Hassainya
- Institut National de la Santé et de la Recherche Médicale Unité 580, Université René Descartes, Paris, France
| | | | | | | | | | | | | | | |
Collapse
|
107
|
Kent SC, Chen Y, Bregoli L, Clemmings SM, Kenyon NS, Ricordi C, Hering BJ, Hafler DA. Expanded T cells from pancreatic lymph nodes of type 1 diabetic subjects recognize an insulin epitope. Nature 2005; 435:224-8. [PMID: 15889096 DOI: 10.1038/nature03625] [Citation(s) in RCA: 312] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2005] [Accepted: 04/11/2005] [Indexed: 11/09/2022]
Abstract
In autoimmune type 1 diabetes, pathogenic T lymphocytes are associated with the specific destruction of insulin-producing beta-islet cells. Identification of the autoantigens involved in triggering this process is a central question. Here we examined T cells from pancreatic draining lymph nodes, the site of islet-cell-specific self-antigen presentation. We cloned single T cells in a non-biased manner from pancreatic draining lymph nodes of subjects with type 1 diabetes and from non-diabetic controls. A high degree of T-cell clonal expansion was observed in pancreatic lymph nodes from long-term diabetic patients but not from control subjects. The oligoclonally expanded T cells from diabetic subjects with DR4, a susceptibility allele for type 1 diabetes, recognized the insulin A 1-15 epitope restricted by DR4. These results identify insulin-reactive, clonally expanded T cells from the site of autoinflammatory drainage in long-term type 1 diabetics, indicating that insulin may indeed be the target antigen causing autoimmune diabetes.
Collapse
Affiliation(s)
- Sally C Kent
- Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | | | | | | | | | | | | | | |
Collapse
|
108
|
Nakayama M, Abiru N, Moriyama H, Babaya N, Liu E, Miao D, Yu L, Wegmann DR, Hutton JC, Elliott JF, Eisenbarth GS. Prime role for an insulin epitope in the development of type 1 diabetes in NOD mice. Nature 2005; 435:220-3. [PMID: 15889095 PMCID: PMC1364531 DOI: 10.1038/nature03523] [Citation(s) in RCA: 568] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2005] [Accepted: 03/08/2005] [Indexed: 12/17/2022]
Abstract
A fundamental question about the pathogenesis of spontaneous autoimmune diabetes is whether there are primary autoantigens. For type 1 diabetes it is clear that multiple islet molecules are the target of autoimmunity in man and animal models. It is not clear whether any of the target molecules are essential for the destruction of islet beta cells. Here we show that the proinsulin/insulin molecules have a sequence that is a primary target of the autoimmunity that causes diabetes of the non-obese diabetic (NOD) mouse. We created insulin 1 and insulin 2 gene knockouts combined with a mutated proinsulin transgene (in which residue 16 on the B chain was changed to alanine) in NOD mice. This mutation abrogated the T-cell stimulation of a series of the major insulin autoreactive NOD T-cell clones. Female mice with only the altered insulin did not develop insulin autoantibodies, insulitis or autoimmune diabetes, in contrast with mice containing at least one copy of the native insulin gene. We suggest that proinsulin is a primary autoantigen of the NOD mouse, and speculate that organ-restricted autoimmune disorders with marked major histocompatibility complex (MHC) restriction of disease are likely to have specific primary autoantigens.
Collapse
Affiliation(s)
- Maki Nakayama
- Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
109
|
|
110
|
Abstract
CD4(+)CD25(+) T-cells can be used to interfere with spontaneous autoimmune diseases such as type 1 diabetes. However, their low frequency and often unknown specificity represent major obstacles to their therapeutic use. Here we have explored the fact that ectopic expression of the transcription factor Foxp3 can confer a suppressor phenotype to naive CD4(+) T-cells. We found that retroviral transduction of polyclonal CD4 T-cells with FoxP3 was not effective in interfering with established type 1 diabetes. Thus, more subtle and more organ-specific regulation might be required to prevent type 1 diabetes, as well as to avoid systemic immunosuppression. However, a single injection of 10(5) FoxP3-transduced T-cells with specificity for islet antigen stabilized and reversed disease in mice with recent-onset diabetes. By comparing FoxP3-transduced T-cells with various antigen specificities, it became clear that the in vivo effect correlated with specific homing to and activation in pancreatic lymph nodes and not with in vitro suppressor activity or cytokine production. Our results complement recent results on in vitro-amplified antigen-specific T-cells in ameliorating type 1 diabetes and suggest that FoxP3 transduction of expanded T-cells might achieve the same goal.
Collapse
Affiliation(s)
- Elmar Jaeckel
- Hannover Medical School, Department of Gastroenterology, Hepatology and Endocrinology, Carl Neuberg Str. 1, 30625 Hannover, Germany.
| | | | | |
Collapse
|
111
|
Roep BO, Atkinson M, von Herrath M. Satisfaction (not) guaranteed: re-evaluating the use of animal models of type 1 diabetes. Nat Rev Immunol 2005; 4:989-97. [PMID: 15573133 DOI: 10.1038/nri1502] [Citation(s) in RCA: 163] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Without a doubt, rodent models have been instrumental in describing pathways that lead to pancreatic beta-cell destruction, evaluating potential causes of type 1 diabetes and providing proof-of-principle for the potential of immune-based interventions. However, despite more than two decades of productive research, we are still yet to define an initiating autoantigen for the human disease, to determine the precise mechanisms of beta-cell destruction in humans and to design interventions that prevent or cure type 1 diabetes. In this Perspective article, we propose that a major philosophical change would benefit this field, a proposition that is based on evaluation of situations in which rodent models have provided useful guidance and in which they have led to disappointments.
Collapse
Affiliation(s)
- Bart O Roep
- Bart O. Roep is at the Leiden University Medical Center, Department of Immunohematology and Blood Transfusion, Leiden NL-2300 RC, The Netherlands.
| | | | | |
Collapse
|