Contributions
Abstract: P1191
Type: Poster
Abstract Category: Therapy - disease modifying - Immunomodulation/Immunosuppression
Background: B cells play an important role in multiple sclerosis (MS), and the understanding of B cell trafficking is highly relevant for defining the role of B cells in MS pathogenesis. Natalizumab and fingolimod are effective MS therapies that interfere with the migration of lymphocytes but exert differential effects on B cells. In order to investigate B cell migration patterns between the periphery and CNS, we compared longitudinal heavy chain (VH) transcriptomes from cerebrospinal fluid (CSF) and peripheral blood (PB) B cells obtained from MS patients receiving either therapy.
Methods: Four MS patients were treated with fingolimod or natalizumab, and their CSF and PB VH transcriptome repertoires were assessed at baseline and after 6 months of treatment. VH repertoires were generated from FACS sorted CSF and PB B cell populations by next generation deep sequencing (Illumina MiSeq) using barcoded primers with unique molecular identifiers.
Results: We established clonal relationships between CSF and PB B cells at baseline and after 6 months treatment in 3 out of 4 fingolimod- and 4 out of 4 natalizumab-treated patients. The average number of CSF and PB B cell VH transcriptome clusters correlated with the number of sorted B cells. As expected, VH clusters recovered from natalizumab-treated patients were increased in PB, but decreased in the CSF. In contrast, the number of B cell VH clusters decreased in the PB but varied in the CSF with fingolimod therapy. Comparative analyses of clonal overlap between CSF and PB B cell clusters revealed reduced overlap under natalizumab treatment (9% at baseline, 4% under treatment) and increased overlap under fingolimod therapy (7% at baseline, 25% under therapy). PB VH clusters showed significantly greater overlap following natalizumab therapy (17%) than following fingolimod therapy (1%). CSF VH clusters overlapped with similar frequency (3.8% following natalizumab therapy and 5.8% following fingolimod therapy).
Conclusions: Our findings suggest that natalizumab treatment might diminish but not completely block the migration of B cells into the CSF. Fingolimod appears to significantly reduce peripheral blood B cell numbers and clonal populations. Surprisingly, these B cells seem to continue to exchange across the blood brain barrier. Additional effects of fingolimod on CNS germinal center activity and B cell exit from the CNS are under investigation.
Disclosure: Kowarik M.C.: received travel funding from Merck-Serono, Bayer Health Care, and Novartis. Additional research support was provided by Novartis and Medigene.
Astling D.: nothing to disclose.
Gasperi C.: nothing to disclose.
Ritchie A.: nothing to disclose.
Owens G.P.: nothing to disclose.
Bennett J.L.: serves as a consultant for Novartis Pharmaceuticals, MedImmune, Chugai Pharmaceuticals, EMD Serono, Abbvie, Genentech, and Genzyme; receives license and royalties for a patent re Compositions and Methods for the Treatment of Neuromyelitis Optica (Aquaporumab); has stock options and serves on the scientific advisory board of Apsara Therapeutics; receives research support from Mallinckrodt Pharmaceuticals, Novartis pharmaceuticals, National Institutes of Health (R01 EY022936), and Guthy-Jackson Foundation; and serves on the editorial boards of the Multiple Sclerosis Journal, Neurology: Neuroimmunology & Neuroinflammation, and Journal of Neuro-ophthalmology.
This study was supported by Novartis, NIH.
Abstract: P1191
Type: Poster
Abstract Category: Therapy - disease modifying - Immunomodulation/Immunosuppression
Background: B cells play an important role in multiple sclerosis (MS), and the understanding of B cell trafficking is highly relevant for defining the role of B cells in MS pathogenesis. Natalizumab and fingolimod are effective MS therapies that interfere with the migration of lymphocytes but exert differential effects on B cells. In order to investigate B cell migration patterns between the periphery and CNS, we compared longitudinal heavy chain (VH) transcriptomes from cerebrospinal fluid (CSF) and peripheral blood (PB) B cells obtained from MS patients receiving either therapy.
Methods: Four MS patients were treated with fingolimod or natalizumab, and their CSF and PB VH transcriptome repertoires were assessed at baseline and after 6 months of treatment. VH repertoires were generated from FACS sorted CSF and PB B cell populations by next generation deep sequencing (Illumina MiSeq) using barcoded primers with unique molecular identifiers.
Results: We established clonal relationships between CSF and PB B cells at baseline and after 6 months treatment in 3 out of 4 fingolimod- and 4 out of 4 natalizumab-treated patients. The average number of CSF and PB B cell VH transcriptome clusters correlated with the number of sorted B cells. As expected, VH clusters recovered from natalizumab-treated patients were increased in PB, but decreased in the CSF. In contrast, the number of B cell VH clusters decreased in the PB but varied in the CSF with fingolimod therapy. Comparative analyses of clonal overlap between CSF and PB B cell clusters revealed reduced overlap under natalizumab treatment (9% at baseline, 4% under treatment) and increased overlap under fingolimod therapy (7% at baseline, 25% under therapy). PB VH clusters showed significantly greater overlap following natalizumab therapy (17%) than following fingolimod therapy (1%). CSF VH clusters overlapped with similar frequency (3.8% following natalizumab therapy and 5.8% following fingolimod therapy).
Conclusions: Our findings suggest that natalizumab treatment might diminish but not completely block the migration of B cells into the CSF. Fingolimod appears to significantly reduce peripheral blood B cell numbers and clonal populations. Surprisingly, these B cells seem to continue to exchange across the blood brain barrier. Additional effects of fingolimod on CNS germinal center activity and B cell exit from the CNS are under investigation.
Disclosure: Kowarik M.C.: received travel funding from Merck-Serono, Bayer Health Care, and Novartis. Additional research support was provided by Novartis and Medigene.
Astling D.: nothing to disclose.
Gasperi C.: nothing to disclose.
Ritchie A.: nothing to disclose.
Owens G.P.: nothing to disclose.
Bennett J.L.: serves as a consultant for Novartis Pharmaceuticals, MedImmune, Chugai Pharmaceuticals, EMD Serono, Abbvie, Genentech, and Genzyme; receives license and royalties for a patent re Compositions and Methods for the Treatment of Neuromyelitis Optica (Aquaporumab); has stock options and serves on the scientific advisory board of Apsara Therapeutics; receives research support from Mallinckrodt Pharmaceuticals, Novartis pharmaceuticals, National Institutes of Health (R01 EY022936), and Guthy-Jackson Foundation; and serves on the editorial boards of the Multiple Sclerosis Journal, Neurology: Neuroimmunology & Neuroinflammation, and Journal of Neuro-ophthalmology.
This study was supported by Novartis, NIH.