Supplementary MaterialsAdditional file 1: Figure S1. For each individual donor at each daratumumab concentration, triplicate wells were combined for quantification in B and D and then normalized to isotype control in C and E. (F) Representative quantification of CD38 MFI on CD56+CD16+ NK cells at 72?h post-culture with isotype control or daratumumab at indicated concentrations. (G) Dose response of CD38 MFI down-regulation on NK cells by daratumumab in patients with SLE or RA and healthy controls combined. Data shown represent four patients with SLE, four with RA and four healthy controls. (PDF 401?kb) 13075_2018_1578_MOESM1_ESM.pdf (402K) GUID:?02F531CC-CF65-4618-BA0C-A7A9EE3CC08B Additional file 2: Figure S2. Daratumumab has no Rabbit Polyclonal to Fos impact on T cells and monocytes ex vivo. (A) Total number of CD3+ T cells in each daratumumab concentration at 72?h post-treatment. (B) Quantification of CD38 MFI on CD3+ T cells at 72?h post-culture with isotype control or daratumumab at indicated concentrations. (C) Total number of CD14+ monocytes in each daratumumab concentration at 72?h post-treatment. (D) Quantification of CD38 MFI on CD14+ monocytes at 72?h post-culture with isotype control or daratumumab at indicated concentrations. Data shown represent four patients with SLE, six with RA and six healthy control donors. (PNG 2127?kb) 13075_2018_1578_MOESM2_ESM.png (2.0M) GUID:?13738424-91AA-4429-9627-5B21431126B4 Data Availability StatementThe datasets generated and/or analyzed during the current study are available in the GEO database [GEO:GSE89408] (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE89408). The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request. All data generated or analyzed during this study are included in this published article and its supplementary information files. Abstract Background Plasmablasts and plasma cells play a key role in many KOS953 manufacturer autoimmune diseases, such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). This study was undertaken to evaluate the potential of targeting CD38 as a plasma cell/plasmablast depletion mechanism by daratumumab in the treatment of patients with RA and SLE. Methods RNA-sequencing analysis of synovial KOS953 manufacturer biopsies from various stages of RA disease progression, flow cytometry analysis of peripheral blood mononuclear cells (PBMC) from patients with RA or SLE and healthy donors, immunohistochemistry assessment (IHC) of synovial biopsies from patients with early RA, and ex vivo immune cell depletion assays using daratumumab (an anti-CD38 monoclonal antibody) were used to assess CD38 as a therapeutic target. Results We demonstrated that the plasma cell/plasmablast-related genes and are significantly up-regulated in KOS953 manufacturer synovial biopsies from patients with arthralgia, undifferentiated arthritis (UA), early RA and established RA as compared to healthy controls and control patients with osteoarthritis. In addition, the highest CD38 expression was observed on plasma cells and plasmablasts compared to natural killer (NK) cells, classical dendritic cells (DCs), plasmacytoid DCs (pDCs) and T cells, in blood from healthy controls and patients with SLE and RA. Furthermore, IHC showed CD38 staining in the same region as CD3 and CD138 staining in synovial tissue biopsies from patients with early RA. Most importantly, our data show for the first time that daratumumab effectively depletes plasma cells/plasmablasts in PBMC from patients with SLE and RA in a dose-dependent manner ex vivo. Conclusion These results indicate that CD38 may be a potential target for RA disease interception and daratumumab should be evaluated clinically for the treatment of both RA and SLE. Electronic supplementary material The online version of this article (10.1186/s13075-018-1578-z) contains supplementary material, which is available to authorized users. statistics were used to assess differences in expression. Fluorescence-activated cell sorting (FACS) analysis PBMC samples were analyzed in three different staining panels for CD38 expression as follows: Panel 1: CD38-FITC, CD14-PE, HLA-DR-PerCPCy5.5, CD11b-PECy7, CD33-APC, BDCA2-VioBlue, CD16-BV510, Lineage (CD3/CD8/CD4/CD19)-BV605, CD45-BV650, CD11c-BV711 and CD56-BV786. Panel 2: CD38-FITC, CD62L-PE, CCR7-PerCPCy5.5, CD27-PECy7, CD4-APC, CD127-BV421, CD8-BV510, CD3-BV605, CD25-BV650 and CD45RA-BV786. Panel 3: CD38-FITC, BCMA-PE, CD24-PerCPCy5.5, IgD-PECy7, CD20-APC, CD27-BV421, IgM-BV510, CD138-BV605, CD3-BV650, CD56-BV650 and CD19-BV711. For the ex vivo depletion assay, a different panel was used to measure NK cells and plasma cells/plasmablast.