2024-03-28T20:15:33Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/805402022-11-17T02:08:08Zhdl_2115_20040hdl_2115_121Anti-cyclic citrullinated peptide antibody titers decrease in rheumatoid arthritis patients treated with tocilizumab : A pilot studyNoguchi, AtsushiYasuda, ShinsukeHisada, RyoKato, MasaruOku, KenjiBohgaki, ToshiyukiSuzuki, MihoMatsumoto, YoshihiroAtsumi, TatsuyaAnti-cyclic citrullinated peptide antibodyB-cell subpopulationrheumatoid arthritistocilizumab490Objectives: To analyze the effects of tocilizumab on peripheral B-cell subpopulation and its ability to produce anti-cyclic citrullinated peptide (CCP) antibody in patients with rheumatoid arthritis (RA). Methods: Thirteen consecutive RA patients initiated with tocilizumab were enrolled in our prospective study. Anti-CCP antibody titers and clinical parameters were evaluated during treatment. Peripheral blood B-cell subsets were analyzed using flow cytometry according to the Human Immunology Project. Results: Disease activity was significantly improved and anti-CCP antibody titers significantly decreased at week 24 compared to baseline. The percentages of post-switch memory B cells in CD19+ cells transiently increased at week 12, but there was no significant difference in any of the investigated B-cell subpopulations at week 24 compared to baseline. The ratios of post-switch memory to naive B cells (post-switch/naive) correlated negatively with anti-CCP antibody titers regardless of the time-points. Conclusion: Our study indicated that tocilizumab has a potential to reduce anti-CCP antibody production presumably by affecting post-switch/naive ratio, and that anti-CCP antibody titers reflect B-cell distribution/subpopulation. As anti-CCP antibodies are produced in lymph nodes or ectopic lymphoid structures in synovial tissues, not in circulation, transient increment of post-switch memory B cells after tocilizumab treatment may reflect the altered balance of B-cell distribution between circulation and arthritic joints, resulting in suppressed production of anti-CCP antibody in situ.Taylor & FrancisJournal Articleapplication/pdfimage/tiffimage/tiffhttp://hdl.handle.net/2115/80540https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/80540/1/Mod%20Rheumatol_30_276.pdfhttps://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/80540/2/Suppl.%20Fig%201.tifhttps://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/80540/3/Suppl.%20Fig%202.tif1439-7595Modern rheumatology3022762812020-03-03enginfo:doi/10.1080/14397595.2019.1583784This is an Accepted Manuscript of an article published by Taylor & Francis in Modern rheumatology on 3 Mar 2020, available online: http://www.tandfonline.com/10.1080/14397595.2019.1583784.author