Contributions
Abstract: P455
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - 15 Immunology
Background: The role of B lymphocytes in MS immunopathogenesis is increasingly recognized. B cells undergo compartmentalized redistribution in blood and cerebrospinal fluid (CSF) during active MS, whereby antigen-experienced memory B-cells accumulate in the CSF. While trafficking of B cells across the blood-brain barrier has been intensively investigated, cellular diapedesis through the blood-CSF barrier (BCSFB) is incompletely understood.
Goals and objectives: To investigate the interaction of B cells with the choroid plexus to transmigrate into the CSF.
Methods: We isolated B cells and B-cell subsets from peripheral blood samples of healthy donors (HC) and MS patients, utilized an inverted transwell culture system of human choroid plexus papilloma (HIBCPP) cells to determine transmigration rates of distinct B-cell subsets, and immunofluorescence microscopy to analyze their migration route through the epithelial barrier. Experiments were completed by cytokine assays and RT-PCR to determine cytokines/chemokines mediating B-cell transmigration.
Results: Transmigration rates of both HC- and MS-derived B cells across HIBCPP were initially low, significantly increased in response to B-cell specific chemokines (including CXCL-12, -13), and were further enhanced following pre-activation (CPG-ODN, CD40/IgM). Migrated cells predominantly exhibited a CD27+ memory phenotype. Interestingly, chemotactic activities of MS-derived memory B cells were higher when compared with HC-derived cells. Exposure of HIBCPP to pro-inflammatory stimuli induced distinct changes in their cytokine/chemokine profiles and permeability during B-cell transmigration.
Conclusions: Our findings provide new information on how antigen-experienced B-cell phenotypes and the BCSFB act together to facilitate aberrant B-cell accumulation in the CSF of MS patients.
Disclosure:
Supported by grants the German Ministry for Education and Research (BMBF, “German Competence Network Multiple Sclerosis” (KKNMS, Research Consortium 3: 'Prognostic and Treatment markers') and the Klaus Tschira Foundation. Funding sources had no role in study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the abstract for publication.
JH, HR, SF, AS, SJ, CS, HS have nothing to disclose.
BW has received honoraria for speaking/consulting and travel grants from Bayer Healthcare, Biogen, Merck Serono, Genzyme, Novartis Pharmaceuticals, Teva Pharma GmbH, and research grants from Biogen, Merck-Serono, Novartis Pharmaceuticals, Teva Pharma GmbH, the German Ministry of Education and Research, the Dietmar Hopp Foundation, and the Klaus Tschira Foundation.
Abstract: P455
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - 15 Immunology
Background: The role of B lymphocytes in MS immunopathogenesis is increasingly recognized. B cells undergo compartmentalized redistribution in blood and cerebrospinal fluid (CSF) during active MS, whereby antigen-experienced memory B-cells accumulate in the CSF. While trafficking of B cells across the blood-brain barrier has been intensively investigated, cellular diapedesis through the blood-CSF barrier (BCSFB) is incompletely understood.
Goals and objectives: To investigate the interaction of B cells with the choroid plexus to transmigrate into the CSF.
Methods: We isolated B cells and B-cell subsets from peripheral blood samples of healthy donors (HC) and MS patients, utilized an inverted transwell culture system of human choroid plexus papilloma (HIBCPP) cells to determine transmigration rates of distinct B-cell subsets, and immunofluorescence microscopy to analyze their migration route through the epithelial barrier. Experiments were completed by cytokine assays and RT-PCR to determine cytokines/chemokines mediating B-cell transmigration.
Results: Transmigration rates of both HC- and MS-derived B cells across HIBCPP were initially low, significantly increased in response to B-cell specific chemokines (including CXCL-12, -13), and were further enhanced following pre-activation (CPG-ODN, CD40/IgM). Migrated cells predominantly exhibited a CD27+ memory phenotype. Interestingly, chemotactic activities of MS-derived memory B cells were higher when compared with HC-derived cells. Exposure of HIBCPP to pro-inflammatory stimuli induced distinct changes in their cytokine/chemokine profiles and permeability during B-cell transmigration.
Conclusions: Our findings provide new information on how antigen-experienced B-cell phenotypes and the BCSFB act together to facilitate aberrant B-cell accumulation in the CSF of MS patients.
Disclosure:
Supported by grants the German Ministry for Education and Research (BMBF, “German Competence Network Multiple Sclerosis” (KKNMS, Research Consortium 3: 'Prognostic and Treatment markers') and the Klaus Tschira Foundation. Funding sources had no role in study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the abstract for publication.
JH, HR, SF, AS, SJ, CS, HS have nothing to disclose.
BW has received honoraria for speaking/consulting and travel grants from Bayer Healthcare, Biogen, Merck Serono, Genzyme, Novartis Pharmaceuticals, Teva Pharma GmbH, and research grants from Biogen, Merck-Serono, Novartis Pharmaceuticals, Teva Pharma GmbH, the German Ministry of Education and Research, the Dietmar Hopp Foundation, and the Klaus Tschira Foundation.