Increased Proportion of CD226 + B Cells Is Associated With the Disease Activity and Prognosis of Systemic Lupus Erythematosus

• Published in: Frontiers in immunology 2021-07, Vol.12, p.713225-713225
• Main Authors: Nakano, Miki, Ayano, Masahiro, Kushimoto, Kazuo, Kawano, Shotaro, Higashioka, Kazuhiko, Inokuchi, Shoichiro, Mitoma, Hiroki, Kimoto, Yasutaka, Akahoshi, Mitsuteru, Ono, Nobuyuki, Arinobu, Yojiro, Akashi, Koichi, Horiuchi, Takahiko, Niiro, Hiroaki
• Format: Article
• Language: English
• Subjects: Adult; Antibodies, Antinuclear - immunology; Antigens, Differentiation, T-Lymphocyte - metabolism; Autoimmunity; B cells; B-Lymphocyte Subsets - immunology; B-Lymphocyte Subsets - metabolism; Biomarkers; CD226; Female; Humans; Immunology; Lupus Erythematosus, Systemic - diagnosis; Lupus Erythematosus, Systemic - etiology; Lupus Erythematosus, Systemic - metabolism; lupus low disease activity; lupus nephritis; Lupus Nephritis - diagnosis; Lupus Nephritis - etiology; Lymphocyte Count; Male; Middle Aged; Prognosis; Severity of Illness Index; systemic lupus erythematosus
• ISSN: 1664-3224; 1664-3224
• DOI: 10.3389/fimmu.2021.713225

CD226, an activating receptor expressed on the surface of natural killer (NK) cells and T cells, is also seen on B cells and CD226 polymorphism is associated with systemic lupus erythematosus (SLE). Because the specific roles of CD226 B cells in SLE are still unknown, we investigated the association of CD226 B cells with SLE. We measured CD226 expression on B cells and its subsets using flow cytometry in 48 SLE patients and 24 healthy controls (HCs). We assessed the relationships between CD226 B cells and SLE Disease Activity Index 2000 (SLEDAI-2K), clinical manifestations, laboratory data, and prognosis after 12 months. The proportions of CD226 cells in whole B cells and all its subsets were significantly higher in SLE patients than HCs. In SLE patients, the proportions of CD226 B cells and CD226 switched-memory (SM) B cells were significantly correlated with SLEDAI-2K scores and anti-dsDNA antibody titers, and negatively correlated with serum complement levels. Moreover, basal percentages of CD226 B cells and CD226 SM B cells were low in patients who were in Lupus Low Disease Activity State after 12 months. In patients with renal involvement, the proportion of CD226 B cells increased. Additionally, the proportion of CD226 B cells was higher in patients who were not in complete renal remission after 12 months. Increased proportion of CD226 B cells was associated with disease activity and prognosis of SLE. CD226 B cells may be a useful biomarker for the management of SLE.