AB0517 Dynamics of B Lymphocyte Subsets Counts in SLE Patients Treated with Rituximab. (9th June 2015)

• Record Type: Journal Article
• Authors: Mesnyankina, A.A.; Aleksandrova, E.N.; Soloviev, S.K.; Aleksankin, A.P.; Gluhova, S.I.; Novikov, A.A.; Aseeva, E.A.; Suponitskaya, E.V.; Nasonov, E.L.
• Is Part Of: Annals of the rheumatic diseases. Volume 74(2015)Supplement 2
• Page Start: 1073
• Page End: 1073
• Publication Date: 2015-06-09
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/annrheumdis-2015-eular.2324
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Objectives: B subsets . To study the correlation between the counts of B cell subsets and SLE activity, and their dynamics after treatment with rituximab. Methods: Rituximab in doses from 500 to 2000 mg was administered to 8 SLE patients with high and moderate disease activity (1 male and 7 females), 6 patients had lupus nephritis. The relative counts of CD19 + B cells, the total population of memory B cells (CD19 + CD27 +), "preswitch" (CD19 + IgD + CD27 +) and "postswitch" (CD19 + IgD-CD27 +) memory B cells, naive (CD19 + IgD + CD27-) and transitional (CD19 + IgD + CD10 + CD38 ++ CD27-) B cells, plasmablasts (CD19 + CD38 +++ IgD-CD27 + CD20-), short-lived plasma cells (CD19 +, CD38 +), long-lived plasma cells (CD19 + CD138 +), and double negative B-cells (CD19 + CD27-IgD-) were measured. All B cell subsets were determined by multi-color flow cytometry using a panel of monoclonal antibodies to B-lymphocytes' surface membrane markers. Statistical analysis was performed using the U Mann-Whitney test. Results: There was no statistically significant correlation between SLE activity and B-cell subsets counts before initiation of rituximab, most likely due to a small sample size. 2-12 scores decrease by SLEDAI2K scale in SLE activity from average 19±5 score "before" to average 11±4 scores "after" was documented already in 3 months after initiation of rituximab. This was accompanied by reduction of CD 19+ levels (median 6.25% (4.2 -10, 5); 0, 1% (0, 05-1, 5), ( p =0, 004;)), count of short-lived plasma cells (CD19 +, CD38 +) (median 5.5% (2, 2-7, 15); 0, 15% (0-1, 3), ( p =0, 008)), memory B cells (CD19 + CD27 +) (median 1% (0, 8-3); 0, 05% (0-0, 4), ( p =0, 01)), and naive (CD19 + IgD + CD27-) B cells (median 42.6% (22, 9-49, 75); 14% (2, 15-21, 2), ( p =0, 01)). Residual CD19 + cells during severe depletion phase were mostly represented by "preswitch" (CD19 + IgD + CD27 +) and "postswitch" (CD19 + IgD-CD27 +) memory B cells, and double negative memory B cells (CD19 + CD27-IgD -). Conclusions: Reduction of SLE clinical activity is associated with accompanying decrease in the counts of short-lived plasma cells (CD19 +, CD38 +), memory B cells (CD19 + CD27 +), naive (CD19 + IgD + CD27-) B-lymphocytes, which most likely indicates that these cells are major targets for anti-B cell therapy, as well as key players in autoimmune process development and progression. Disclosure of Interest: None declared