biostudies-literatureMiura Ygrants-in-aid from the Ministry of Education, Culture, Sports, Science and Technology (MEXT)/JSPS KAKENHIBristol-Myers Squibb K.K. and Ono Pharmaceutical Co., LTD16363https://www.ebi.ac.uk/biostudies/studies/S-EPMC9525600biostudies-literatureUnknown12(1)CD80 interact with CD28 and CTLA-4 on antigen-presenting cells, and function in the co-stimulatory signaling that regulates T cell activity. CTLA-4-Ig is used to treat RA by blocking co-stimulatory signaling. Chronic inflammatory arthritis was induced in D1BC mice using low-dose arthritogenic antigens and treated with CTLA-4-Ig. We performed histopathology of the joints and lymph nodes, serological examination for rheumatoid factors, and flow cytometric analysis of isolated synovial cells, including CD45^- FLSs and CD45⁺ synovial macrophages. CTLA-4-Ig treatment ameliorated the chronic inflammatory polyarthritis. There was a decrease in the number of infiltrating lymphoid cells in the joints as well as in the levels of RF-IgG associated with a decrease in the number ofScientific reportsCTLA-4-Ig internalizes CD80 in fibroblast-like synoviocytes from chronic inflammatory arthritis mouse model.PMC9525600JP 20K17447JP 26461470Kanazawa SMiura YMaeda SIsogai SfalseCTLA-4-Ig internalizes CD80 in fibroblast-like synoviocytes from chronic inflammatory arthritis mouse model.CD80 interact with CD28 and CTLA-4 on antigen-presenting cells, and function in the co-stimulatory signaling that regulates T cell activity. CTLA-4-Ig is used to treat RA by blocking co-stimulatory signaling. Chronic inflammatory arthritis was induced in D1BC mice using low-dose arthritogenic antigens and treated with CTLA-4-Ig. We performed histopathology of the joints and lymph nodes, serological examination for rheumatoid factors, and flow cytometric analysis of isolated synovial cells, including CD45^- FLSs and CD45⁺ synovial macrophages. CTLA-4-Ig treatment ameliorated the chronic inflammatory polyarthritis. There was a decrease in the number of infiltrating lymphoid cells in the joints as well as in the levels of RF-IgG associated with a decrease in the number of2022-01-01T00:00:00Z2022 Sep2026-07-14T15:49:49.383Z2025-02-19T00:23:47.616ZS-EPMC95256003618052610.1038/s41598-022-20694-7