Human insulin-dependent diabetes mellitus (IDDM) is thought to result from the autoimmune destruction of the insulin-production islet cells of the pancreas. The autoimmune hypothesis is supported by the association of the disease with autoantibodies specific for islet cell antigen (ICA) and human leukocyte antigen (HLA) alleles that convey susceptibility and resistance, and also by rodent models of IDDM that clearly show T cell-mediated autoimmune etiology. In the rodent models, CD4 and CD8 cells both seem to contribute to the destruction of islet cells. Presently, it is unclear whether the lessons learned from the rodent models also hold for the human disease. In particular, it has been difficult to obtain consistent data in support of the hypothesis that activated, ICA-specific T cells are present in patients, as opposed to healthy controls, whether these cells were primed in vivo to a Th1-type or Th2-type memory state, and whether they belong to the CD4 or CD8 category. The lack of this central information can be attributed to technical limitations in the measurement of T cell reactivity in freshly isolated cellular material, which are the primary goal of this application to overcome. The first limitation is the difficulty in detecting the low frequency antigen-reactive cells. The Investigator has overcome this limitation by developing a cytokine ELISPOT system that has single cell resolution such that it is able to detect the cytokine response of a single antigen-specific T cells within a million bystander cells. The second limitation is the failure of the present assays to detect CD8 cell responses. This application has two specific aims. 1) To modify the cytokine ELISPOT system in a manner that it can also detect CD8 responses to ICA, also at single cell resolution. The another limitation is the inability of standard assays to detect T cell responses to cryptic determinants on autoantigens, due to which the bulk of the autoreactive repertoire may be missed. 2) To use a modification of the ELISPOT assay that should detect responses to cryptic determinants on ICA as well. By further expanding the limits of T cell diagnostics, this proposal provides the tools and the initial measurements required to understand the very cells that mediate the disease and thereby foster new therapeutic controls.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21AI044484-01
Application #
2767453
Study Section
Special Emphasis Panel (ZAI1-PTM-I (S1))
Project Start
1998-09-30
Project End
2000-09-29
Budget Start
1998-09-30
Budget End
1999-09-29
Support Year
1
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Case Western Reserve University
Department
Pathology
Type
Schools of Medicine
DUNS #
077758407
City
Cleveland
State
OH
Country
United States
Zip Code
44106
Schlingmann, Tobias R; Rininsland, Frauke H; Bartholomae, Wolf C et al. (2009) Vaccination with tumor cells pulsed with foreign peptide induces immunity to the tumor itself. Clin Immunol 133:45-51
Ott, Patrick A; Tary-Lehmann, Magdalena; Lehmann, Paul V (2007) The secretory IFN-gamma response of single CD4 memory cells after activation on different antigen presenting cell types. Clin Immunol 124:267-76
Ott, Patrick A; Herzog, Bernhard A; Quast, Stefan et al. (2005) Islet-cell antigen-reactive T cells show different expansion rates and Th1/Th2 differentiation in type 1 diabetic patients and healthy controls. Clin Immunol 115:102-14
Ott, Patrick A; Anderson, Michael R; Tary-Lehmann, Magdalena et al. (2005) CD4+CD25+ regulatory T cells control the progression from periinsulitis to destructive insulitis in murine autoimmune diabetes. Cell Immunol 235:1-11
Ott, Patrick A; Dittrich, Marcus T; Herzog, Bernhard A et al. (2004) T cells recognize multiple GAD65 and proinsulin epitopes in human type 1 diabetes, suggesting determinant spreading. J Clin Immunol 24:327-39
Darabi, Kamruz; Karulin, Alexey Y; Boehm, Bernhard O et al. (2004) The third signal in T cell-mediated autoimmune disease? J Immunol 173:92-9
Herzog, Bernhard A; Ott, Patrick A; Dittrich, Marcus T et al. (2004) Increased in vivo frequency of IA-2 peptide-reactive IFNgamma+/IL-4- T cells in type 1 diabetic subjects. J Autoimmun 23:45-54
Hofstetter, Harald H; Sewell, Diane L; Liu, Frances et al. (2003) Autoreactive T cells promote post-traumatic healing in the central nervous system. J Neuroimmunol 134:25-34
Karulin, Alexey Y; Hesse, Maike D; Yip, Hualin C et al. (2002) Indirect IL-4 pathway in type 1 immunity. J Immunol 168:545-53
Targoni, O S; Baus, J; Hofstetter, H H et al. (2001) Frequencies of neuroantigen-specific T cells in the central nervous system versus the immune periphery during the course of experimental allergic encephalomyelitis. J Immunol 166:4757-64

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