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Chella S David - One of the best experts on this subject based on the ideXlab platform.
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dqb1 0602 rather than drb1 1501 confers susceptibility to multiple sclerosis like disease induced by proteolipid protein plp
Journal of Neuroinflammation, 2012Co-Authors: Nathali Kaushansky, Daniel M Altmann, Chella S David, Hans Lassmann, Avraham BennunAbstract:Multiple sclerosis (MS) is associated with pathogenic autoimmunity primarily focused on major CNS-myelin target antigens including myelin basic protein (MBP), proteolipidprotein (PLP), myelin oligodendrocyte protein (MOG). MS is a complex trait whereby the HLA genes, particularly class-II genes of HLA-DR15 haplotype, dominate the genetic contribution to disease-risk. Due to strong linkage disequilibrium in HLA-II region, it has been hard to establish precisely whether the functionally relevant effect derives from the DRB1*1501, DQA1*0102-DQB1*0602, or DRB5*0101 loci of HLA-DR15 haplotype, their combinations, or their epistatic interactions. Nevertheless, most genetic studies have indicated DRB1*1501 as a primary risk factor in MS. Here, we used 'HLA-humanized' mice to discern the potential relative contribution of DRB1*1501 and DQB1*0602 alleles to susceptibility to "humanized" MS-like disease induced by PLP, one of the most prominent and encephalitogenic target-antigens implicated in human MS. The HLA-DRB1*1501- and HLA-DQB1*0602-Tg mice (MHC-II-/-), and control non-HLA-DR15-relevant-Tg mice were immunized with a set of overlapping PLP peptides or with recombinant soluble PLP for induction of "humanized" MS-like disease, as well as for ex-vivo analysis of immunogenic/immunodominant HLA-restricted T-cell epitopes and associated cytokine secretion profile. PLP autoimmunity in both HLA-DR15-Tg mice was focused on 139-151 and 175-194 epitopes. Strikingly, however, the HLA-DRB1*1501-transgenics were refractory to disease induction by any of the overlapping PLP peptides, while HLA-DQB1*0602 transgenics were susceptible to disease induction by PLP139-151 and PLP175-194 peptides. Although both transgenics responded to both peptides, the PLP139-151- and PLP175-194-reactive T-cells were directed to Th1/Th17 phenotype in DQB1*0602-Tg mice and towards Th2 in DRB1*1501-Tg mice. While genome studies map a strong MS susceptibility effect to the region of DRB1*1501, our findings offer a rationale for potential involvement of pathogenic DQ6-associated autoimmunity in MS. Moreover, that DQB1*0602, but not DRB1*1501, determines disease-susceptibility to PLP in HLA-transgenics, suggests a potential differential, functional role for DQB1*0602 as a predisposing allele in MS. This, together with previously demonstrated disease-susceptibility to MBP and MOG in DRB1*1501-transgenics, also suggests a differential role for DRB1*1501 and DQB1*0602 depending on target antigen and imply a potential complex 'genotype/target antigen/phenotype' relationship in MS heterogeneity.
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identification of t cell epitopes on human proteolipid protein and induction of experimental autoimmune encephalomyelitis in hla class ii transgenic mice
European Journal of Immunology, 2004Co-Authors: Ashutosh K Mangalam, Meenakshi Khare, Christopher J Krco, Moses Rodriguez, Chella S DavidAbstract:Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the CNS that is associated with HLA class II molecules HLA-DR2, -DR3 and -DR4. Previously, it has been difficult to analyze the role of individual HLA molecules in disease pathogenesis due to heterogeneity of MHC genes, linkage disequilibrium, influence of non-MHC genes and contribution of environment. To overcome some of these problems, we have generated HLA-transgenic (tg) mice to investigate function and interaction of these molecules in disease pathogenesis. To investigate the role of individual HLA class II genes in immune responses to human proteolipid protein (PLP), a candidate autoantigen in MS, mice expressing HLA genes DR2, DR3, DR4 (DRB1*0401 and DRB1*0402), DQ6 and DQ8, lacking endogenous class II molecules were immunized with overlapping peptides of PLP. In all tg mice, the majority of the dominant T cell epitopes were clustered mainly to three region; amino acids 31-70, 91-120 and 178-228, of the PLP molecules. We also identified an encephalitogenic epitope PLP(91-110) that induced clinical EAE in HLA-DR3 tg mice. These tg mice had inflammatory infiltrates classically associated with EAE and showed a Th1 cytokine profile. This humanized mouse model of MS will be valuable in deciphering the role of HLA molecules and autoantigens in MS.
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a humanized model of experimental autoimmune uveitis in hla class ii transgenic mice
Journal of Clinical Investigation, 2003Co-Authors: Giuseppina Pennesi, Chella S David, Mary J Mattapallil, Shu Hui Sun, Dody Avichezer, Phyllis B Silver, Zaruhi Karabekian, Paul A Hargrave, Hugh J Mcdowell, Clay W SmithAbstract:Experimental autoimmune uveitis (EAU) is a disease of the neural retina induced by immunization with retinal antigens, such as interphotoreceptor retinoid-binding protein (IRBP) and arrestin (retinal soluble antigen, S-Ag). EAU serves as a model for human autoimmune uveitic diseases associated with major histocompatibility complex (HLA) genes, in which patients exhibit immunological responses to retinal antigens. Here we report the development of a humanized EAU model in HLA transgenic (TG) mice. HLA-DR3, -DR4, -DQ6, and -DQ8 TG mice were susceptible to IRBP-induced EAU. Importantly, HLA-DR3 TG mice developed severe EAU with S-Ag, to which wild-type mice are highly resistant. Lymphocyte proliferation was blocked by anti-HLA antibodies, confirming that antigen is functionally presented by the human MHC molecules. Disease could be transferred by immune cells with a Th1-like cytokine profile. Antigen-specific T cell repertoire, as manifested by responses to overlapping peptides derived from S-Ag or IRBP, differed from that of wild-type mice. Interestingly, DR3 TG mice, but not wild-type mice, recognized an immunodominant S-Ag epitope between residues 291 and 310 that overlaps with a region of S-Ag recognized by uveitis patients. Thus, EAU in HLA TG mice offers a new model of uveitis that should represent human disease more faithfully than currently existing models.
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hla dq determines the response to exogenous wheat proteins a model of gluten sensitivity in transgenic knockout mice
Journal of Immunology, 2002Co-Authors: Kay E Black, Joseph A Murray, Chella S DavidAbstract:We have investigated the genetic basis of the immune response to dietary gluten in HCD4/DQ8 and HCD4/DQ6 double transgenic mice. Mice were immunized with gluten i.p. or individual peptides s.c. and spleen or draining lymph node T cells were challenged in vitro. Strong proliferative responses to gluten were seen in the HCD4/DQ8 mice, whereas the HCD4/DQ6 mice responded to gluten poorly. A series of overlapping peptides spanning gliadin were synthesized. The HCD4/DQ8 mice reacted to many of the individual peptides of gliadin, while the HCD4/DQ6 mice were relatively unresponsive. T cells isolated from HCD4/DQ8 mice also responded well to modified (deamidated) versions of the gliadin peptides, whereas HCD4DQ6 mice did not. The T cell response to gluten was CD4 dependent and DQ restricted and led to the production of cytokines IL-6, TGF-β, and IL-10. Finally, intestinal lymphocytes isolated from gluten-fed HCD4/DQ8 mice displayed an activated phenotype. These data suggest that this HLA class II transgenic murine model of gluten sensitivity may provide insight into the initiation of the MHC class II-restricted gluten sensitivity in celiac disease.
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co expression of hla dr3 and dq8 results in the development of spontaneous insulitis and loss of tolerance to gad65 in transgenic mice
Diabetes, 2000Co-Authors: Roshini S Abraham, Jack L Strominger, Yogish C Kudva, S B Wilson, Chella S DavidAbstract:Specific HLA DQ and DR alleles have been associated with susceptibility to type 1 diabetes. HLA DQ8 and DQ2 have been shown to strongly predispose to disease and to be in linkage disequilibrium with at-risk DR4 and DR3 alleles, respectively. Inheritance of a mixed DR3/DR4 haplotype confers the greatest risk. A double transgenic mouse expressing both DR3 and DQ8 was generated to investigate potential major histocompatibility complex class II interactions. The DR3/DQ8 transgenic mice developed a spontaneous loss of tolerance to GAD65, in which the T-cell response to GAD65 was restricted by HLA DR. Although the mice also showed spontaneous insulitis, they did not progress to overt diabetes. Mice expressing either transgene (DQ8 or DR3) alone showed mild infiltration of their islets, which disappeared when DQ8 or DR3 was co-expressed with a resistant DR2 allele or the neutral DQ6 allele. Therefore, in a fashion analogous to human diabetes, the murine model demonstrated a requirement for a combination of at-risk DR and DQ allotypes for the initiation of spontaneous autoimmunity.
Don C Wiley - One of the best experts on this subject based on the ideXlab platform.
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crystal structure of hla dr2 dra 0101 drb1 1501 complexed with a peptide from human myelin basic protein
Journal of Experimental Medicine, 1998Co-Authors: Kathrine J Smith, Jason Pyrdol, Laurent Gauthier, Don C Wiley, Kai W WucherpfennigAbstract:Susceptibility to multiple sclerosis is associated with the human histocompatibility leukocyte antigen (HLA)-DR2 (DRB1*1501) haplotype. The structure of HLA-DR2 was determined with a bound peptide from human myelin basic protein (MBP) that is immunodominant for human MBP-specific T cells. Residues of MBP peptide that are important for T cell receptor recognition are prominent, solvent exposed residues in the crystal structure. A distinguishing feature of the HLA-DR2 peptide binding site is a large, primarily hydrophobic P4 pocket that accommodates a phenylalanine of the MBP peptide. The necessary space for this aromatic side chain is created by an alanine at the polymorphic DRβ 71 position. These features make the P4 pocket of HLA-DR2 distinct from DR molecules associated with other autoimmune diseases.
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expression and crystallization of the complex of hla dr2 dra drb1 1501 and an immunodominant peptide of human myelin basic protein
Proceedings of the National Academy of Sciences of the United States of America, 1998Co-Authors: Laurent Gauthier, Jason Pyrdol, Jack L Strominger, Kathrine J Smith, Don C Wiley, Avtandil Kalandadze, Kai W WucherpfennigAbstract:HLA-DR2 is associated with susceptibility to multiple sclerosis (MS). A peptide from human myelin basic protein (MBP, residues 85-99) was previously found to bind to purified HLA-DR2 (DRA, DRB1*1501) and to be recognized by human MBP-specific T cell clones. Soluble HLA-DR2 was expressed in the baculovirus system by replacing the hydrophobic transmembrane regions and cytoplasmic segments of DRalpha and DRbeta with leucine zipper dimerization domains from the transcription factors Fos and Jun. In the expression construct, the MBP(85-99) sequence was covalently linked to the N terminus of the mature DRbeta chain. The recombinant protein was secreted by Sf9 cells infected with the recombinant baculovirus and purified by affinity chromatography. The leucine zipper dimerization domains were then cleaved from the assembled HLA-DR2/MBP peptide complex with V8 protease, and the protein was further purified by anion-exchange HPLC. Analysis by HPLC gel filtration indicated that the HLA-DR2/MBP peptide complex did not have a tendency to aggregate. The purified HLA-DR2/MBP peptide complex readily crystallized by the hanging drop method in 15-18% polyethylene glycol 6000/100 mM glycine, pH 3.5. At a synchrotron radiation source, a crystal with a tetragonal space group diffracted to a resolution of 2.6 A. The expression of such homogenous HLA-DR/peptide complexes may facilitate cocrystallization with T cell receptors as well as other molecules involved in T cell receptor recognition and signaling.
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three dimensional structure of the human class ii histocompatibility antigen hla dr1
Nature, 1993Co-Authors: Lawrence J. Stern, Jack L Strominger, Jerry H Brown, Theodore S Jardetzky, Joan C Gorga, Robert G Urban, Don C WileyAbstract:The three-dimensional structure of the class II histocompatibility glycoprotein HLA-DR1 from human B-cell membranes has been determined by X-ray crystallography and is similar to that of class I HLA. Peptides are bound in an extended conformation that projects from both ends of an 'open-ended' antigen-binding groove. A prominent non-polar pocket into which an 'anchoring' peptide side chain fits is near one end of the binding groove. A dimer of the class II αβ heterodimers is seen in the crystal forms of HLA-DR1, suggesting class II HLA dimerization as a mechanism for initiating the cytoplasmic signalling events in T-cell activation.
Kai W Wucherpfennig - One of the best experts on this subject based on the ideXlab platform.
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crystal structure of hla dr2 dra 0101 drb1 1501 complexed with a peptide from human myelin basic protein
Journal of Experimental Medicine, 1998Co-Authors: Kathrine J Smith, Jason Pyrdol, Laurent Gauthier, Don C Wiley, Kai W WucherpfennigAbstract:Susceptibility to multiple sclerosis is associated with the human histocompatibility leukocyte antigen (HLA)-DR2 (DRB1*1501) haplotype. The structure of HLA-DR2 was determined with a bound peptide from human myelin basic protein (MBP) that is immunodominant for human MBP-specific T cells. Residues of MBP peptide that are important for T cell receptor recognition are prominent, solvent exposed residues in the crystal structure. A distinguishing feature of the HLA-DR2 peptide binding site is a large, primarily hydrophobic P4 pocket that accommodates a phenylalanine of the MBP peptide. The necessary space for this aromatic side chain is created by an alanine at the polymorphic DRβ 71 position. These features make the P4 pocket of HLA-DR2 distinct from DR molecules associated with other autoimmune diseases.
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expression and crystallization of the complex of hla dr2 dra drb1 1501 and an immunodominant peptide of human myelin basic protein
Proceedings of the National Academy of Sciences of the United States of America, 1998Co-Authors: Laurent Gauthier, Jason Pyrdol, Jack L Strominger, Kathrine J Smith, Don C Wiley, Avtandil Kalandadze, Kai W WucherpfennigAbstract:HLA-DR2 is associated with susceptibility to multiple sclerosis (MS). A peptide from human myelin basic protein (MBP, residues 85-99) was previously found to bind to purified HLA-DR2 (DRA, DRB1*1501) and to be recognized by human MBP-specific T cell clones. Soluble HLA-DR2 was expressed in the baculovirus system by replacing the hydrophobic transmembrane regions and cytoplasmic segments of DRalpha and DRbeta with leucine zipper dimerization domains from the transcription factors Fos and Jun. In the expression construct, the MBP(85-99) sequence was covalently linked to the N terminus of the mature DRbeta chain. The recombinant protein was secreted by Sf9 cells infected with the recombinant baculovirus and purified by affinity chromatography. The leucine zipper dimerization domains were then cleaved from the assembled HLA-DR2/MBP peptide complex with V8 protease, and the protein was further purified by anion-exchange HPLC. Analysis by HPLC gel filtration indicated that the HLA-DR2/MBP peptide complex did not have a tendency to aggregate. The purified HLA-DR2/MBP peptide complex readily crystallized by the hanging drop method in 15-18% polyethylene glycol 6000/100 mM glycine, pH 3.5. At a synchrotron radiation source, a crystal with a tetragonal space group diffracted to a resolution of 2.6 A. The expression of such homogenous HLA-DR/peptide complexes may facilitate cocrystallization with T cell receptors as well as other molecules involved in T cell receptor recognition and signaling.
Takehiko Sasazuki - One of the best experts on this subject based on the ideXlab platform.
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functional interaction between human histocompatibility leukocyte antigen hla class ii and mouse cd4 molecule in antigen recognition by t cells in hla dr and dq transgenic mice
Journal of Experimental Medicine, 1994Co-Authors: Ken Yamamoto, Yoshinori Fukui, Kazuaki Yamane, Takeshi Inamitsu, Nobuhiro Kamikawaji, Yukio Esaki, Tohm Sudo, Akinori Kimura, Takehiko SasazukiAbstract:Studies in vitro have suggested that a species barrier exists in functional interaction between human histocompatibility leukocyte antigen (HLA) class II and mouse CD4 molecules. However, whether mouse CD4+ T cells restricted by HLA class II molecules are generated in HLA class II transgenic mice and respond to peptide antigens across this barrier has remained unclear. In an analysis of T cell responses to synthetic peptides in mice transgenic for HLA-DR51 and -DQ6, we found that DR51 and DQ6 transgenic mice acquired significant T cell response to influenza hemagglutinin-derived peptide 307-319 (HA 307) and Streptococcus pyogenes M12 protein-derived peptide 347-397 (M6C2), respectively. Inhibition studies with several monoclonal antibodies showed that transgenic HLA class II molecules presented these peptides to mouse CD4+ T cells. Furthermore, T cell lines specific for HA 307 or M6C2 obtained from the transgenic mice could respond to the peptide in the context of relevant HLA class II molecules expressed on mouse L cell transfectants that lack the expression of mouse MHC class II. These findings indicate that interaction between HLA class II and mouse CD4 molecules is sufficient for provoking peptide-specific HLA class II-restricted T cell responses in HLA class II transgenic mice.
Jack L Strominger - One of the best experts on this subject based on the ideXlab platform.
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co expression of hla dr3 and dq8 results in the development of spontaneous insulitis and loss of tolerance to gad65 in transgenic mice
Diabetes, 2000Co-Authors: Roshini S Abraham, Jack L Strominger, Yogish C Kudva, S B Wilson, Chella S DavidAbstract:Specific HLA DQ and DR alleles have been associated with susceptibility to type 1 diabetes. HLA DQ8 and DQ2 have been shown to strongly predispose to disease and to be in linkage disequilibrium with at-risk DR4 and DR3 alleles, respectively. Inheritance of a mixed DR3/DR4 haplotype confers the greatest risk. A double transgenic mouse expressing both DR3 and DQ8 was generated to investigate potential major histocompatibility complex class II interactions. The DR3/DQ8 transgenic mice developed a spontaneous loss of tolerance to GAD65, in which the T-cell response to GAD65 was restricted by HLA DR. Although the mice also showed spontaneous insulitis, they did not progress to overt diabetes. Mice expressing either transgene (DQ8 or DR3) alone showed mild infiltration of their islets, which disappeared when DQ8 or DR3 was co-expressed with a resistant DR2 allele or the neutral DQ6 allele. Therefore, in a fashion analogous to human diabetes, the murine model demonstrated a requirement for a combination of at-risk DR and DQ allotypes for the initiation of spontaneous autoimmunity.
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expression and crystallization of the complex of hla dr2 dra drb1 1501 and an immunodominant peptide of human myelin basic protein
Proceedings of the National Academy of Sciences of the United States of America, 1998Co-Authors: Laurent Gauthier, Jason Pyrdol, Jack L Strominger, Kathrine J Smith, Don C Wiley, Avtandil Kalandadze, Kai W WucherpfennigAbstract:HLA-DR2 is associated with susceptibility to multiple sclerosis (MS). A peptide from human myelin basic protein (MBP, residues 85-99) was previously found to bind to purified HLA-DR2 (DRA, DRB1*1501) and to be recognized by human MBP-specific T cell clones. Soluble HLA-DR2 was expressed in the baculovirus system by replacing the hydrophobic transmembrane regions and cytoplasmic segments of DRalpha and DRbeta with leucine zipper dimerization domains from the transcription factors Fos and Jun. In the expression construct, the MBP(85-99) sequence was covalently linked to the N terminus of the mature DRbeta chain. The recombinant protein was secreted by Sf9 cells infected with the recombinant baculovirus and purified by affinity chromatography. The leucine zipper dimerization domains were then cleaved from the assembled HLA-DR2/MBP peptide complex with V8 protease, and the protein was further purified by anion-exchange HPLC. Analysis by HPLC gel filtration indicated that the HLA-DR2/MBP peptide complex did not have a tendency to aggregate. The purified HLA-DR2/MBP peptide complex readily crystallized by the hanging drop method in 15-18% polyethylene glycol 6000/100 mM glycine, pH 3.5. At a synchrotron radiation source, a crystal with a tetragonal space group diffracted to a resolution of 2.6 A. The expression of such homogenous HLA-DR/peptide complexes may facilitate cocrystallization with T cell receptors as well as other molecules involved in T cell receptor recognition and signaling.
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three dimensional structure of the human class ii histocompatibility antigen hla dr1
Nature, 1993Co-Authors: Lawrence J. Stern, Jack L Strominger, Jerry H Brown, Theodore S Jardetzky, Joan C Gorga, Robert G Urban, Don C WileyAbstract:The three-dimensional structure of the class II histocompatibility glycoprotein HLA-DR1 from human B-cell membranes has been determined by X-ray crystallography and is similar to that of class I HLA. Peptides are bound in an extended conformation that projects from both ends of an 'open-ended' antigen-binding groove. A prominent non-polar pocket into which an 'anchoring' peptide side chain fits is near one end of the binding groove. A dimer of the class II αβ heterodimers is seen in the crystal forms of HLA-DR1, suggesting class II HLA dimerization as a mechanism for initiating the cytoplasmic signalling events in T-cell activation.