{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:49:37Z","timestamp":1787028577685,"version":"build-2736575974"},"reference-count":36,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2025,11,23]],"date-time":"2025-11-23T00:00:00Z","timestamp":1763856000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001700","name":"Ministry of Education, Culture, Sports, Science, and Technology","doi-asserted-by":"crossref","award":["S1311011"],"award-info":[{"award-number":["S1311011"]}],"id":[{"id":"10.13039\/501100001700","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Japan Society for the Promotion of Science (JSPS) KAKENHI","award":["JP22K09365"],"award-info":[{"award-number":["JP22K09365"]}]},{"name":"Japan Society for the Promotion of Science (JSPS) KAKENHI","award":["JP19K09608"],"award-info":[{"award-number":["JP19K09608"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Belimumab, a fully humanized B cell-activating factor (BAFF)-targeting monoclonal antibody, inhibits autoreactive B cell survival and improves systemic lupus erythematosus (SLE) clinical outcomes. However, its administration criteria remain unclear. To establish a basis for defining these criteria, we characterized the immune cell subpopulation alterations post-belimumab treatment and elucidated the underlying mechanisms. We hypothesized that belimumab modulates specific cell subsets and investigated the post-therapy changes. Flow cytometry and correlation analysis revealed that the frequency of B- and T-lymphocyte attenuator (BTLA)high memory B cells in peripheral blood and clinical improvement after belimumab treatment. Western blotting analysis of healthy control B cells revealed that BTLA engagement suppressed Bruton tyrosine kinase and phospholipase C-gamma 2 phosphorylation, which was enhanced by B cell and BAFF receptor co-stimulation. BTLA-expressing memory B cells, which positively correlate with disease improvement, possibly contributed to SLE improvement via BTLA-mediated signaling that attenuated B cell- and BAFF receptor-induced intracellular pathways. To validate these findings, we plan to further assess the effects of belimumab on BTLA expression and B cell signaling pathways in treatment-naive patients with SLE by western blotting. Collectively, our results provide a novel foundation for establish appropriate belimumab administration criteria.<\/jats:p>","DOI":"10.3390\/ijms262311323","type":"journal-article","created":{"date-parts":[[2025,11,24]],"date-time":"2025-11-24T09:02:07Z","timestamp":1763974927000},"page":"11323","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["BTLA-Expressing Memory B Cells Are Associated with Belimumab-Induced Improvement in Systemic Lupus Erythematosus"],"prefix":"10.3390","volume":"26","author":[{"given":"Takuya","family":"Nishi","sequence":"first","affiliation":[{"name":"Institute for Environment and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Tomioka Urayasu-Shi, Chiba 279-0021, Japan"},{"name":"Department of Internal Medicine and Rheumatology, Juntendo University Urayasu Hospital, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8053-746X","authenticated-orcid":false,"given":"Kunihiro","family":"Hayakawa","sequence":"additional","affiliation":[{"name":"Institute for Environment and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Tomioka Urayasu-Shi, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8032-7147","authenticated-orcid":false,"given":"Keigo","family":"Ikeda","sequence":"additional","affiliation":[{"name":"Institute for Environment and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Tomioka Urayasu-Shi, Chiba 279-0021, Japan"},{"name":"Department of Internal Medicine and Rheumatology, Juntendo University Urayasu Hospital, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maki","family":"Fujishiro","sequence":"additional","affiliation":[{"name":"Institute for Environment and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Tomioka Urayasu-Shi, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuko","family":"Kataoka","sequence":"additional","affiliation":[{"name":"Institute for Environment and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Tomioka Urayasu-Shi, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ken","family":"Yamaji","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine and Rheumatology, School of Medicine, Juntendo University, Tokyo 113-8421, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0644-0504","authenticated-orcid":false,"given":"Kenji","family":"Takamori","sequence":"additional","affiliation":[{"name":"Institute for Environment and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Tomioka Urayasu-Shi, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1729-2954","authenticated-orcid":false,"given":"Naoto","family":"Tamura","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine and Rheumatology, School of Medicine, Juntendo University, Tokyo 113-8421, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iwao","family":"Sekigawa","sequence":"additional","affiliation":[{"name":"Institute for Environment and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Tomioka Urayasu-Shi, Chiba 279-0021, Japan"},{"name":"Department of Internal Medicine and Rheumatology, Juntendo University Urayasu Hospital, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shinji","family":"Morimoto","sequence":"additional","affiliation":[{"name":"Institute for Environment and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Tomioka Urayasu-Shi, Chiba 279-0021, Japan"},{"name":"Department of Internal Medicine and Rheumatology, Juntendo University Urayasu Hospital, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1196\/annals.1313.004","article-title":"BAFF overexpression is associated with autoantibody production in autoimmune diseases","volume":"1050","author":"Pers","year":"2005","journal-title":"Ann. N. Y. Acad. Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2453","DOI":"10.1002\/art.23678","article-title":"Association of plasma B lymphocyte stimulator levels and disease activity in systemic lupus erythematosus","volume":"58","author":"Petri","year":"2008","journal-title":"Arthritis Rheum."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"586","DOI":"10.1093\/toxsci\/kfj148","article-title":"Chronic administration of belimumab, a BLyS antagonist, decreases tissue and peripheral blood B-lymphocyte populations in cynomolgus monkeys: Pharmacokinetic, pharmacodynamic, and toxicologic effects","volume":"91","author":"Halpern","year":"2006","journal-title":"Toxicol. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"865","DOI":"10.1007\/s00296-017-3682-9","article-title":"Belimumab use, clinical outcomes and glucocorticoid reduction in patients with systemic lupus erythematosus receiving belimumab in clinical practice settings: Results from the OBSErve Canada Study","volume":"37","author":"Touma","year":"2017","journal-title":"Rheumatol. Int."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1117","DOI":"10.1056\/NEJMoa2001180","article-title":"Two-year, randomized, controlled trial of belimumab in lupus nephritis","volume":"383","author":"Furie","year":"2020","journal-title":"N. Engl. J. Med."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"670","DOI":"10.1038\/ni944","article-title":"BTLA is a lymphocyte inhibitory receptor with similarities to CTLA-4 and PD-1","volume":"4","author":"Watanabe","year":"2003","journal-title":"Nat. Immunol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2498","DOI":"10.1002\/art.23674","article-title":"Development of autoimmune hepatitis-like disease and production of autoantibodies to nuclear antigens in mice lacking B and T lymphocyte attenuator","volume":"58","author":"Oya","year":"2008","journal-title":"Arthritis Rheum."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1116","DOI":"10.1073\/pnas.0409071102","article-title":"A coreceptor interaction between the CD28 and TNF receptor family members B and T lymphocyte attenuator and herpesvirus entry mediator","volume":"102","author":"Gonzalez","year":"2005","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1038\/ni1144","article-title":"B and T lymphocyte attenuator regulates T cell activation through interaction with herpesvirus entry mediator","volume":"6","author":"Sedy","year":"2005","journal-title":"Nat. Immunol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1007\/s00109-012-0943-7","article-title":"CpG-ODN-induced sustained expression of BTLA mediating selective inhibition of human B cells","volume":"91","author":"Thibult","year":"2013","journal-title":"J. Mol. Med."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"335","DOI":"10.1093\/intimm\/dxr017","article-title":"Lack of B and T lymphocyte attenuator exacerbates autoimmune disorders and induces Fas-independent liver injury in MRL-lpr\/lpr mice","volume":"23","author":"Oya","year":"2011","journal-title":"Int. Immunol."},{"key":"ref_12","first-page":"260","article-title":"Changes in the gene expression of peripheral blood mononuclear cells during the menstrual cycle of females is associated with a gender bias in the incidence of systemic lupus erythematosus","volume":"27","author":"Kawasaki","year":"2009","journal-title":"Clin. Exp. Rheumatol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"e99711","DOI":"10.1172\/jci.insight.99711","article-title":"Defective BTLA functionality is rescued by restoring lipid metabolism in lupus CD4+ T cells","volume":"3","author":"Sawaf","year":"2018","journal-title":"JCI Insight"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"3918","DOI":"10.1002\/art.30613","article-title":"A phase III, randomized, placebo-controlled study of belimumab, a monoclonal antibody that inhibits B lymphocyte stimulator, in patients with systemic lupus erythematosus","volume":"63","author":"Furie","year":"2011","journal-title":"Arthritis Rheum."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1002\/art.27189","article-title":"Effect of long-term belimumab treatment on B cells in systemic lupus erythematosus: Extension of a phase II, double-blind, placebo-controlled, dose-ranging study","volume":"62","author":"Jacobi","year":"2010","journal-title":"Arthritis Rheum."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"517","DOI":"10.1016\/j.ebiom.2018.12.035","article-title":"B cell alterations during BAFF inhibition with belimumab in SLE","volume":"40","author":"Ramskold","year":"2019","journal-title":"eBioMedicine"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Wiedemann, A., Lettau, M., Weissenberg, S.Y., Stefanski, A.L., Schrezenmeier, E.V., Rincon-Arevalo, H., Reiter, K., Alexander, T., Hiepe, F., and Lino, A.C. (2021). BTLA expression and function are impaired on SLE B cells. Front. Immunol., 12.","DOI":"10.3389\/fimmu.2021.667991"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1002\/cpt.3282","article-title":"B- and T-lymphocyte attenuator in systemic lupus erythematosus disease pathogenesis","volume":"116","author":"Vendel","year":"2024","journal-title":"Clin. Pharmacol. Ther."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1804","DOI":"10.1126\/science.272.5269.1804","article-title":"Aberrant B cell development and immune response in mice with a compromised BCR complex","volume":"272","author":"Torres","year":"1996","journal-title":"Science"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"822","DOI":"10.1126\/science.271.5250.822","article-title":"Activation of BTK by a phosphorylation mechanism initiated by SRC family kinases","volume":"271","author":"Rawlings","year":"1996","journal-title":"Science"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1084\/jem.184.1.31","article-title":"A role for Bruton\u2019s tyrosine kinase in B cell antigen receptor-mediated activation of phospholipase C-gamma 2","volume":"184","author":"Takata","year":"1996","journal-title":"J. Exp. Med."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1509","DOI":"10.4049\/jimmunol.182.3.1509","article-title":"B and T lymphocyte attenuator regulates B cell receptor signaling by targeting Syk and BLNK","volume":"182","author":"Vendel","year":"2009","journal-title":"J. Immunol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1038\/nri1629","article-title":"Control of lymphocyte development by nuclear factor-kappa B","volume":"5","author":"Siebenlist","year":"2005","journal-title":"Nat. Rev. Immunol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"958","DOI":"10.1038\/ni842","article-title":"BAFF-induced NEMO-independent processing of NF-kappa B2 in maturing B cells","volume":"3","author":"Claudio","year":"2002","journal-title":"Nat. Immunol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"3872","DOI":"10.4049\/jimmunol.179.6.3872","article-title":"Bruton\u2019s tyrosine kinase mediates NF-kappa B activation and B cell survival by B cell-activating factor receptor of the TNF-R family","volume":"179","author":"Shinners","year":"2007","journal-title":"J. Immunol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"975","DOI":"10.1007\/s40744-022-00454-9","article-title":"Real-world effectiveness of belimumab in systemic lupus erythematosus: A systematic literature review","volume":"9","author":"Huang","year":"2022","journal-title":"Rheumatol. Ther."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1136\/ard-2023-224762","article-title":"EULAR recommendations for the management of systemic lupus erythematosus: 2023 update","volume":"83","author":"Fanouriakis","year":"2024","journal-title":"Ann. Rheum. Dis."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1016","DOI":"10.1002\/art.40049","article-title":"Efficacy and safety of subcutaneous belimumab in systemic lupus erythematosus: A fifty-two-week randomized, double-blind, placebo-controlled study","volume":"69","author":"Stohl","year":"2017","journal-title":"Arthritis Rheumatol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1168","DOI":"10.1002\/art.24699","article-title":"A phase II, randomized, double-blind, placebo-controlled, dose-ranging study of belimumab in patients with active systemic lupus erythematosus","volume":"61","author":"Wallace","year":"2009","journal-title":"Arthritis Rheum."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"104532","DOI":"10.1016\/j.cellimm.2022.104532","article-title":"The role of the BTLA-HVEM complex in the pathogenesis of autoimmune diseases","volume":"376","author":"Wojciechowicz","year":"2022","journal-title":"Cell Immunol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"310","DOI":"10.1016\/j.immuni.2019.05.022","article-title":"The HVEM-BTLA axis restrains T cell help to germinal center B cells and functions as a cell-extrinsic suppressor in lymphomagenesis","volume":"51","author":"Mintz","year":"2019","journal-title":"Immunity"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Aubergeon, L., Felten, R., Gottenberg, J.E., Dumortier, H., and Monneaux, F. (2024). Subset of DN memory B cells expressing low levels of inhibitory receptor BTLA is enriched in SLE patients. Cells, 13.","DOI":"10.3390\/cells13242063"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"566","DOI":"10.1016\/j.imbio.2010.09.016","article-title":"Syk mediates BCR- and CD40-signaling integration during B cell activation","volume":"216","author":"Ying","year":"2011","journal-title":"Immunobiology"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1050","DOI":"10.1002\/art.1780390625","article-title":"Malignancy in systemic lupus erythematosus","volume":"39","author":"Gladman","year":"1996","journal-title":"Arthritis Rheum."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"2677","DOI":"10.1002\/art.34473","article-title":"Derivation and validation of the Systemic Lupus International Collaborating Clinics classification criteria for systemic lupus erythematosus","volume":"64","author":"Petri","year":"2012","journal-title":"Arthritis Rheum."},{"key":"ref_36","first-page":"288","article-title":"Systemic lupus erythematosus disease activity index 2000","volume":"29","author":"Gladman","year":"2002","journal-title":"J. Rheumatol."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/26\/23\/11323\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,11,25]],"date-time":"2025-11-25T05:10:40Z","timestamp":1764047440000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/26\/23\/11323"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,23]]},"references-count":36,"journal-issue":{"issue":"23","published-online":{"date-parts":[[2025,12]]}},"alternative-id":["ijms262311323"],"URL":"https:\/\/doi.org\/10.3390\/ijms262311323","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,23]]}}}