Check GAD antibody positivity with the Diamyd anti-GAD RIA plate*

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References1. Quinn A, et al,MHC class I-restricted determinants on the glutamicacid decarboxylase 65 molecule induce spontaneousCTL activity.J Immunol. 2001;167:1748-57.2. Bowie L, et al,Generation and maintenance of autoantigen-specificCD8+ T cell clones isolated from NOD mice.J. Immunol. Methods. 1999;228:87-95.3. Gauvrit A, et al,Identification of a relevant GAD65 H-2Kd-restrictedepitope recognized by CD8+ T cells in NOD mice.2003. Unpublished data.4. Bach J-M, et al,High affinity presentation of an autoantigenic peptidein Type I diabetes by an HLA class II protein encodedin a haplotype protecting from disease.J. Autoimmun. 19975. Bach JM, et al,Identification of mimicry peptides based on structuralmotifs of epitopes derived from 65-kDa glutamic aciddecarboxylase.Eur. J. Immunol. 1998;28:1902-1910.6. Endl J, et al,Identification of naturally processed T cell epitopesfrom glutamic acid decarboxylase presented in the contextof HLA-Dr. alleles by T lymphocytes of recentonset IDDM patients.J. Clin. Invest. 1997;99:2405-2415.J.-M. Bach, Ph.D., D.V.M., is AssistantProfessor in Endocrinology and Director ofthe ImmunoendocrinologyUnit of Nantes, France. Doctor Bach hasspecialized in the study of the cellularimmune response to GAD in Type 1 diabetes(mouse, dog and human).GAD Peptide Vaccines forT1DM:Not Just a Blueprint?TJ.-M. Bachype 1 diabetes is an autoimmunedisease resulting in thedestruction of pancreatic islet ß-cells, which secrete insulin, byautoreactive T lymphocytes.One of the major challenges ofthe new century will be the treatment of organspecificautoimmune disease. For Type 1 diabetes, itmeans disease prevention before the completedestruction of the ß-cell mass, or replacement ofinsulin-secretive cells after their disappearance.Pancreas and isletcell transplantation are effectiveß-cell replacement therapy for diabetes, but theshortage of human donor pancreata has led tosearch for potential alternative sources of isleT cells(pig islets, in vitro generation of ß-cells from pancreaticduct cells or from stem cells). Beside replacementapproaches, diabetes prevention implicatesthe development of immunotherapies, especiallyspecific immunomodulations of auto-antigensinvolved in Type 1 diabetes pathogenesis.Immunotherapies are also necessary for extensive ß-cell replacement approaches, to block the autoimmmuneprocess and to avoid strong immunosuppressortreatments. To be attractive, immunotherapiesof Type 1 diabetes have to produce a long-lastingprotective response specific for self-antigens.On one hand, specific modulations and tolerancecould be obtained in rodent models withwhole self-proteins or DNA encoding auto-antigens.On a second hand, synthetic peptide-basedvaccines could be a very attractive approach forspecific immunomodulations, permitting to targetclonal elimination or unresponsiveness of aggressiveT cells. Peptides can be produced in largequantities with high purity at low cost, and aresafer than recombinant proteins. To allow thedesign of antigen-specific immune therapies targetingpathogenic autoreactive T cells, we need tocharacterize peptide specificities of autoreactive Tcells, which should also provide fabulous markersof isleT cell damage, useful for therapeutic trialsand diagnosis of individuals with increased riskfor disease, and could help to unravel the pathophysiologyof autoimmune diabetes.Several self-antigens have been identified in Type1 diabetes. Among them, GAD (Glutamic AcidDecarboxylase) is a crucial early target involved indiabetes in human and non-obese diabetic (NOD)mouse. Its role is considered presently as decisive inautoimmunity initiation as well as in progression toovert disease. A majority of studies of diabetes autoimmunityprocess and prevention are focused onthis autoantigen. In rodent models, the role of apeculiar set of T lymphocytes, expressing the CD8marker, in ß-cell aggression is not clearly understood.CD8 + T cells could be implicated not only in diabetesinduction, but also in progression to destructiveinsulitis and overt diabetes. Teams of E. Sercarz (1)and A. Cooke (2) have identified two peptides derivedfrom GAD and recognized by CD8 + T lymphocytesin NOD mouse (peptide 546 and 515,respectively). CD8 + T cells specific for these peptidesare detected early in young NOD mouse. Oursquad have very recently specific another GADderivedpeptide (peptide 90), which may be crucialin diabetes progression in mice [3]. For the firsttime, we showed that CD8 + T cells specific for aGAD-derived peptide are implicated in diabetesaggravation. Specific cytotoxic CD8 + T cells wereactivated and could play an important role in progressionof insulitis to overt disease. We presentlytest immunoprevention of spontaneous diabetes inNOD mice using CD8 + T cell-inducing peptides.And in humans? In humans, while autoantibodyresponses have been extensively characterized,very little is known of the natural history of Tcell autoreactivities, neither for CD8 + T cells (probablythe first T lymphocytes to colonize pancreaticislets), nor for T lymphocytes expressing CD4antigen. We and others have already identifiedGAD-derived peptides presented to CD4 + T lymphocytesof recent-onset diabetic patients[4-6]. Inhumans, we need also to identify relevant CD8 + Tcell-inducing peptides of GAD. In the future, discoveryof GAD-peptides recognized by self-reactiveaggressive CD8 + T lymphocytes and elucidationof key immunological events leading to diabetesinitiation or aggravation in humans may permit todefine efficient peptide-vaccine strategies.page 22 dmccad june 2003
No GAD No Type 1 Diabetes?TJi-Won Yoon, Hee-Sook Jun and Julia McFarlanehe prevention of Type 1 diabeteshas long been a primaryarea of research for our laboratory.Several ß cell autoantigenshave been implicated in thetriggering of ß cell-specificautoimmunity, and GAD65 is a strong candidatein both humans and the diabetes-prone nonobesediabetic (NOD) mouse, which is one of the bestanimal models for human autoimmune diabetes.In the NOD mouse, GAD, as compared withother ß cell autoantigens examined, provokes theearliest T cell proliferative response.We hypothesized that GAD expression in the ßcells may be important for disease initiation. Toaddress this, we took a transgenic approach and selectivelysuppressed GAD expression in the ß cells ofNOD mice. We found that complete suppression ofGAD expression in the ß cells of anti-sense GADtransgenic mice ([SJL x C57BL/6] F2 mice) backcrosssedwith NOD mice resulted in the prevention ofautoimmune Type 1 diabetes. These results supportthe hypothesis that GAD may play an important rolein the development of T cell-mediated autoimmunediabetes. However, we cannot exclude the possibilitythat diabetes-resistance genes from the founder micemay have been transmitted to the anti-sense GADtransgenic mice. To address this issue, we are presentlyexamining the development of insulitis and diabetesin ß cell-specific GAD knock-out NOD mice to confirmthe role of GAD in the initiation of Type 1autoimmune diabetes.Several different approaches for immune therapyusing GAD have been tried for the prevention ofdiabetes in animal models. We used a recombinantvaccinia virus (rVV) expressing GAD as a vaccine,as rVVs can induce humoral and cell-mediatedimmune responses to target proteins and the inducedimmune responses can be long lived. We wereable to show that administration of GAD-expresssingrVV effectively prevented autoimmune diabetesin an age- and dose-dependent manner throughactive suppression of effector T cells in NOD mice.Although the therapeutic effect of GAD-basedimmunotherapy is different depending on theroute of administration, experimental conditions,and quality of antigen, treatment using GAD maybe of importance with regard to future strategiesfor the prevention of Type 1 diabetes in humans.What is theGenetic Basis of T1DM?Michael Clare-SalzlerDr. Ji-Won Yoon holds aCanada Research Chairin Diabetes and is thedirector of the Laboratoryof Viral andImmunopathogenesis ofDiabetes in the Facultyof Medicine, Universityof Calgary. Previously, Yoon spent 10 years as asenior investigator at the National Institutesof Health. Over the past 5 years, Yoon hasbeen involved in studies on the role of glutamicacid decarboxylase (GAD) in the pathogenesisof diabetes and the development of methodsto prevent autoimmune diabetes byimmunogene therapy using recombinant vaccciniavirus vectors expressing GAD.The goal of my research is to establishthe cellular, molecular, andgenetic basis for the immunopathogenesisof Type 1 diabetes(T1D) and to develop methodsto prevent this disease. I haveconcentrated on identifying autoantigens and determiningthe role of antigen presenting cells, e.g. dendriticcells (DC), in T1D. Our publications wereamong the first defining glutamate decarboxylase(GAD) as an autoantigen. Our subsequent studiesdemonstrated GAD administration prevented diseasein diabetes-prone NOD mice. Recently, the NIHbaseddiabetes prevention study, TrialNet, developedplans for a trial to test whether GAD administrationprevents T1D in humans.Michael Clare-Salzler, MD. Professor ofPathology, Immunology and LaboratoryMedicine, University of Florida, Director ofResearch and Academic affairs, research; part ofthe UCLA team that characterized GAD as anautoantigen in NOD mice, demonstrated GADresponses in NOD mice, study of the role antigenpresenting cells in Type 1 diabetes, first todemonstrate a tolerogenic role for dendritic cellsin the autoimmunity of the NOD mouse, first labto demonstrate abnormal regulation Cox-2regulation and prostaglandin metabolism in Type1 diabetes.10090807060Percent Diabetic5040GAD in GraphsInduction of GAD65-specific regulatoryT cells modulates diabetes inNOD mice30alone20 + OVA T cells+ GAD T cells10010 20 30 40 50 60Days Post TransferTisch et al. (1998) Induction of GAD65-specificregulatory T cells inhibits ongoing autoimmunediabetes in nonobese diabetic miceDiabetes 47:894-899Insulitis severity• Irradiated NOD mice developdiabetes when diabetogenicsplenic cells are transferred alone orcotransfered with OVA-specific Tcells.• Cotransfer of GAD-specificregulatory T cells prevents diabetesdevelopmentImmunization with GAD65 does notinduce murine diabetesA2.01.51.00.50.0C2.01.51.00.5BALB/cB2.01.51.00.50.0D2.01.51.00.5C57B10.00.0NMRINODPlesner et al. (1998) Immunization of diabetesproneor non-diabetes-prone mice with GAD65does not induce diabetes or islet cell pathologyJ Autoimmunity 11:335-341• 11 wk old NOD mice were injectedtwice sc with 75mg GAD65 or BSA.• Non-diabetes prone mice (Balb/c,C57/Bl and NMRI) did not developdiabetes.• NOD mice injected with GAD65developed less insulitisdmccad june 2003page 23
Page 4 and 5: forewordResearch Scientists through
Page 6 and 7: The Story ofGADRobert Dinsmoor1975R
Page 8 and 9: Åke Lernmark, MD, Ph.D., and his c
Page 10 and 11: theory, the immune system mistakenl
Page 12 and 13: GAD Back to the Future…Åke Lernm
Page 14 and 15: 100GAD in GraphsGAD65 DNA vaccinati
Page 16 and 17: In Nature, Anything that CanHappen
Page 18 and 19: References1. Baekkeskov, S., et al,
Page 20 and 21: GAD in GraphsIncidence of diabetes
Page 24 and 25: References1. Tisch, R., et al,Induc
Page 26 and 27: Vaccination with GAD PlasmidSuppres
Page 28 and 29: GADGAD in GraphsGAD ELISPOT outperf
Page 30 and 31: GAD in GraphsA1004 wks of age% Inci
Page 32 and 33: Mark Atkinson, Ph.D.,is an American
Page 34 and 35: GAD in GraphsIL-4 (pg/ml)2501007550
Page 36 and 37: References1. Kobayashi T, et al,Isl
Page 38 and 39: References1. A.Falorni, et al,Radio
Page 40 and 41: References1. Chattopadhyay, S., et
Page 42 and 43: Diamyd’s Commercial Development o
Page 44: T cell GAD65For use of GAD in immun

Check GAD antibody positivity with the Diamyd anti-GAD RIA plate*

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