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The identity of oligoclonal bands in patients with multiple sclerosis
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Abstracts
encephalomyelitis (EAE). However, due to the indirect clinical evidence for B cell antigen presentation during EAE and MS, we chose to explore the role of antigen presentation by myelin antigen-specific B cells. We hypothesized that antigen presentation by cognate antigen-specific B cells during EAE is sufficient to support CD4mediated neuroinflammation. We induced active EAE using MOG protein or peptide immunization and induced passive EAE using encephalitogenic CD4 T cell lines in mice expressing MHCII by DCs alone and those in which B cells are deficient in MHCII expression. Further, we examined mice expressing MHCII by B cells alone with or without an increase in precursor frequency for MOG-specific B cell receptors. We found that maximal disease in protein-induced active EAE models is dependent upon B cell antigen presentation. Further, increasing the precursor frequency of MOG-specific B cells, but not the addition of soluble MOG-specific antibody, is sufficient to facilitate passive EAE in mice expressing MHCII by B cells alone. This is the first direct demonstration in vivo that B cells can serve as the sole APC and coordinate CD4 T cell autoreactivity to myelin antigens during EAE. These data support a model in which expansion of antigen-specific B cells during CNS autoimmunity amplifies cognate interactions between B and CD4 T cells and independently drives neuro-inflammation at later stages of disease.
doi:10.1016/j.jneuroim.2014.08.045
291 Intrathecal IgG from patients with multiple sclerosis target patient-specific phage peptides Tiffany Pointona, Sean Mantona, Mollie Davisa, Gino Braiottaa, Laura Schambersa, Taylor Edwardsa, Bailey Polonskya, Michael Granera, Mark Burgoona, Xiaoli Yua a
University of Colorado Anschutz Medical Campus, Neurology, Aurora, United States
Background: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) with demyelination and neuronal damage, and is the most common cause of neurological disability in young adults. A characteristic feature of the CNS inflammatory response in MS is the intrathecal synthesis of IgG and the presence of oligoclonal bands (OCBs). The specificity of the OCBs is unknown. Objectives: To investigate the specificity of the intrathecal IgG and OCBs by panning phage-displayed random peptide libraries. Methods: We applied CSF IgG obtained from 10 MS patients to screen phage-displayed random peptide libraries (7-mer and 12-mer). We characterized the binding specificity of phage peptides with highly sensitive phage-mediated immuno-PCR, and immunoblotting of MS CSF separated on isoelectric focusing (IEF) gels. Results: We identified multiple high-affinity phage peptides for the CSF IgG from each patient. Phage-mediated immuno-PCR demonstrated that the phage peptides exhibited greater binding to intrathecal IgG of MS CSF compared to the serum from the same patient. IEF immunoblots showed that these peptides were recognized by OCBs in MS CSF. Furthermore, when representative phage peptides from each of the 10 patients were used to screen binding specificity with CSF from 32 MS patients and 13 inflammatory controls with phage-mediated immuno-PCR, only 2 phage peptides were found to share antigen reactivity with 2 additional MS patients. Sequence alignment analysis of the peptides from the 10 MS patients revealed that they represent epitopes which share homology with
proteins involved in cell stress, apoptosis, and inflammatory processes. Conclusions: We identified distinct sets of high-affinity epitopes reacting to the intrathecal IgG in CSF from each of the 10 MS patient studied. These data suggest that the intrathecal IgG may target patient-specific antigens. doi:10.1016/j.jneuroim.2014.08.046
515 The identity of oligoclonal bands in patients with multiple sclerosis Tiffany Pointon, Alec Sundet, Nadeen Ibrahim, Timothy Vollmer, Xiaoli Yu Department of Neurology, University of Colorado School of Medicine, Aurora, United States Multiple sclerosis (MS) is the most common autoimmune inflammatory demyelinating disease of the central nervous system with a frequently relapsing or progressive course. A characteristic feature of MS is the increased intrathecal synthesis of IgG and the presence of oligoclonal bands (OCBs) in the brain and CSF. Once present, the intrathecal synthesis of IgG remains stable over time. Furthermore, OCBs are associated with a more rapid conversion from clinically isolated syndrome to clinically definite MS, and treatment with Natalizumab decreases CSF IgG levels and eliminates OCB. The combined studies provide evidence that the increased intrathecal IgG and OCBs play critical role in disease pathogenesis of MS. Using various immunoassays, we investigated the antigen-specific antibody profiles of CSF with paired sera in 7 OCB-positive MS patients. We found that the significantly increased levels of antigen-specific IgG in the CSF consisted of antigen–antibody immune complexes which correspond to OCB. Furthermore, the OCB can be completely eliminated by immunoadsorption, and can be recovered after binding to the specific antigen. The identification of the nature of OCB in MS opens up opportunities for novel diagnostics and prognostics, and provides strategies to design safer and more effective treatments for MS and other CNS inflammatory demyelinating diseases. doi:10.1016/j.jneuroim.2014.08.047
646 Number of OCBs in CSF at diagnosis timepoint,— predictor of long term radiological outcome in MS? V.D. Karrenbauera, B. Evertssonb, L. Stawiarza, K. Imrella, O. Voevodskayacc, L-O. Wahlundc, J. Hillerta, E. Westmanc, D. Ferreirac a
Karolinska Institutet, Department of Clinical Neuroscience, Stockholm, Sweden; bKarolinska University Hospital, Department of Neurology, R52, Stockholm, Sweden; cKarolinska Institutet, Department of Neurobiology, Care Sciences and Society, Stockholm, Sweden Background: Recent study has shown that carriership of oligoclonal bands (OCB) in CSF effects grey matter volume and presence of OCB correlates with larger volumes of CSF and total white matter (WM) lesions and smaller volumes at specific neuro-anatamical areas for grey matter (GM) (basal ganglia, diencephalon, cerebellum, and hippocampus) and WM (corpus callosum, periventricular-deep WM, brainstem, and cerebellum) (Ferreira et al., 2014).
Abstracts
encephalomyelitis (EAE). However, due to the indirect clinical evidence for B cell antigen presentation during EAE and MS, we chose to explore the role of antigen presentation by myelin antigen-specific B cells. We hypothesized that antigen presentation by cognate antigen-specific B cells during EAE is sufficient to support CD4mediated neuroinflammation. We induced active EAE using MOG protein or peptide immunization and induced passive EAE using encephalitogenic CD4 T cell lines in mice expressing MHCII by DCs alone and those in which B cells are deficient in MHCII expression. Further, we examined mice expressing MHCII by B cells alone with or without an increase in precursor frequency for MOG-specific B cell receptors. We found that maximal disease in protein-induced active EAE models is dependent upon B cell antigen presentation. Further, increasing the precursor frequency of MOG-specific B cells, but not the addition of soluble MOG-specific antibody, is sufficient to facilitate passive EAE in mice expressing MHCII by B cells alone. This is the first direct demonstration in vivo that B cells can serve as the sole APC and coordinate CD4 T cell autoreactivity to myelin antigens during EAE. These data support a model in which expansion of antigen-specific B cells during CNS autoimmunity amplifies cognate interactions between B and CD4 T cells and independently drives neuro-inflammation at later stages of disease.
doi:10.1016/j.jneuroim.2014.08.045
291 Intrathecal IgG from patients with multiple sclerosis target patient-specific phage peptides Tiffany Pointona, Sean Mantona, Mollie Davisa, Gino Braiottaa, Laura Schambersa, Taylor Edwardsa, Bailey Polonskya, Michael Granera, Mark Burgoona, Xiaoli Yua a
University of Colorado Anschutz Medical Campus, Neurology, Aurora, United States
Background: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) with demyelination and neuronal damage, and is the most common cause of neurological disability in young adults. A characteristic feature of the CNS inflammatory response in MS is the intrathecal synthesis of IgG and the presence of oligoclonal bands (OCBs). The specificity of the OCBs is unknown. Objectives: To investigate the specificity of the intrathecal IgG and OCBs by panning phage-displayed random peptide libraries. Methods: We applied CSF IgG obtained from 10 MS patients to screen phage-displayed random peptide libraries (7-mer and 12-mer). We characterized the binding specificity of phage peptides with highly sensitive phage-mediated immuno-PCR, and immunoblotting of MS CSF separated on isoelectric focusing (IEF) gels. Results: We identified multiple high-affinity phage peptides for the CSF IgG from each patient. Phage-mediated immuno-PCR demonstrated that the phage peptides exhibited greater binding to intrathecal IgG of MS CSF compared to the serum from the same patient. IEF immunoblots showed that these peptides were recognized by OCBs in MS CSF. Furthermore, when representative phage peptides from each of the 10 patients were used to screen binding specificity with CSF from 32 MS patients and 13 inflammatory controls with phage-mediated immuno-PCR, only 2 phage peptides were found to share antigen reactivity with 2 additional MS patients. Sequence alignment analysis of the peptides from the 10 MS patients revealed that they represent epitopes which share homology with
proteins involved in cell stress, apoptosis, and inflammatory processes. Conclusions: We identified distinct sets of high-affinity epitopes reacting to the intrathecal IgG in CSF from each of the 10 MS patient studied. These data suggest that the intrathecal IgG may target patient-specific antigens. doi:10.1016/j.jneuroim.2014.08.046
515 The identity of oligoclonal bands in patients with multiple sclerosis Tiffany Pointon, Alec Sundet, Nadeen Ibrahim, Timothy Vollmer, Xiaoli Yu Department of Neurology, University of Colorado School of Medicine, Aurora, United States Multiple sclerosis (MS) is the most common autoimmune inflammatory demyelinating disease of the central nervous system with a frequently relapsing or progressive course. A characteristic feature of MS is the increased intrathecal synthesis of IgG and the presence of oligoclonal bands (OCBs) in the brain and CSF. Once present, the intrathecal synthesis of IgG remains stable over time. Furthermore, OCBs are associated with a more rapid conversion from clinically isolated syndrome to clinically definite MS, and treatment with Natalizumab decreases CSF IgG levels and eliminates OCB. The combined studies provide evidence that the increased intrathecal IgG and OCBs play critical role in disease pathogenesis of MS. Using various immunoassays, we investigated the antigen-specific antibody profiles of CSF with paired sera in 7 OCB-positive MS patients. We found that the significantly increased levels of antigen-specific IgG in the CSF consisted of antigen–antibody immune complexes which correspond to OCB. Furthermore, the OCB can be completely eliminated by immunoadsorption, and can be recovered after binding to the specific antigen. The identification of the nature of OCB in MS opens up opportunities for novel diagnostics and prognostics, and provides strategies to design safer and more effective treatments for MS and other CNS inflammatory demyelinating diseases. doi:10.1016/j.jneuroim.2014.08.047
646 Number of OCBs in CSF at diagnosis timepoint,— predictor of long term radiological outcome in MS? V.D. Karrenbauera, B. Evertssonb, L. Stawiarza, K. Imrella, O. Voevodskayacc, L-O. Wahlundc, J. Hillerta, E. Westmanc, D. Ferreirac a
Karolinska Institutet, Department of Clinical Neuroscience, Stockholm, Sweden; bKarolinska University Hospital, Department of Neurology, R52, Stockholm, Sweden; cKarolinska Institutet, Department of Neurobiology, Care Sciences and Society, Stockholm, Sweden Background: Recent study has shown that carriership of oligoclonal bands (OCB) in CSF effects grey matter volume and presence of OCB correlates with larger volumes of CSF and total white matter (WM) lesions and smaller volumes at specific neuro-anatamical areas for grey matter (GM) (basal ganglia, diencephalon, cerebellum, and hippocampus) and WM (corpus callosum, periventricular-deep WM, brainstem, and cerebellum) (Ferreira et al., 2014).