Journal: Nature Communications

Article Title: γ-secretase directly sheds the survival receptor BCMA from plasma cells

doi: 10.1038/ncomms8333

Figure Lengend Snippet: ( a ) Human purified B cells were activated for 5 days as indicated; IgG and sBCMA in the supernatant were quantified using ELISA. Combined data of three independent experiments (mean±s.e.m., P =0.0073, paired t -test). ( b ) PBMCs were stimulated with R848+IL-2 for 7 days. IgG and sBCMA in the supernatant were quantified using ELISA. Combined data of three independent experiments (mean±s.e.m., P =0.0227, paired t -test). ( c – e ) Human purified B cells were stimulated with CD40L+IL-21. ( c ) surface BCMA was measured using flow cytometry on unstimulated B cells, CD19 + CD38 − cells and CD19 + CD38 + cells. ( d ) Sorted CD38 + and CD38 − cells were cultured for another 24 h and the amount of shed sBCMA was measured using ELISA, combined data of two independent experiments. ( e ) Correlation between sBCMA release and surface expression of BCMA for a single replicate. ( f , g ) sBCMA was immunoprecipitated from supernatant of plasmacytoma cells ( f , lanes 1, 2), serum ( f , lane 3) and from supernatant of human purified B cells cultured with CD40L plus IL-21 ( f , lane 4) with anti-BCMA monoclonal antibodies (mAbs) A7D12.2 ( f , lanes 1 and 4) or C12A3.2 ( f , lane 2) or goat-anti-BCMA ( f , lane 3). Western blot analysis for BCMA ( f ) and silver staining of sBCMA immunoprecipitated from plasmacytoma supernatant ( g ) was performed. ( h ) The band at 6 kDa (from g ) and sBCMA obtained using immunoprecipitation were analysed with mass spectrometry. The aa sequences of BCMA and peptides identified after tryptic (blue) or chymotryptic (red) digestion are shown. No peptide was detected with a C-terminal aa that was not a site for either tryptic or chymotryptic cleavage, indicating that the precise cleavage site of γ-secretase within the membrane needs to be identified.

Article Snippet: Supernatants generated by HEK293T cells that had been transfected with full-length BCMA (OriGene Technologies, Inc., Rockville) or an empty control vector and therefore either contained sBCMA or did not, were added at a final sBCMA concentration of 200 ng ml −1 and 400 ng ml −1 .

Techniques: Purification, Enzyme-linked Immunosorbent Assay, Flow Cytometry, Cell Culture, Expressing, Immunoprecipitation, Bioprocessing, Western Blot, Silver Staining, Mass Spectrometry, Membrane

Journal: Nature Communications

Article Title: γ-secretase directly sheds the survival receptor BCMA from plasma cells

doi: 10.1038/ncomms8333

Figure Lengend Snippet: ( a , b ) Human B cells were differentiated into Ig-secreting cells via CD40L+IL-21. ( a ) Release of sBCMA on treatment with DAPT or TAPI-1 was measured using ELISA. sBCMA release was normalized to the amount of sBCMA shed under vehicle conditions, which was set as 100%. Combined data of three independent experiments (mean±s.e.m.). ( b ) These activated primary human B cells were subgrouped on the basis of expression of CD27 and CD38. A high surface expression of BCMA was seen on the CD27 ++ CD38 + subset. Surface expression of BCMA was enhanced using DAPT treatment (1 μM), while TAPI-I (50 μM) had little effect. ( c , d ) Human PBMCs were stimulated with R848+IL-2 for 7 days. ( c ) Release of sBCMA on treatment with DAPT or TAPI-1 was measured using ELISA. sBCMA release was normalized to the amount of sBCMA shed under vehicle conditions, which was set as 100%. Combined data of three independent experiments (mean±s.e.m.). ( d ) High surface expression of BCMA was seen on the CD19 + CD38 + subset; this was further enhanced by DAPT (1 μM), while TAPI-I (50 μM) had little effect.

Article Snippet: Supernatants generated by HEK293T cells that had been transfected with full-length BCMA (OriGene Technologies, Inc., Rockville) or an empty control vector and therefore either contained sBCMA or did not, were added at a final sBCMA concentration of 200 ng ml −1 and 400 ng ml −1 .

Techniques: Enzyme-linked Immunosorbent Assay, Expressing

Journal: Nature Communications

Article Title: γ-secretase directly sheds the survival receptor BCMA from plasma cells

doi: 10.1038/ncomms8333

Figure Lengend Snippet: ( a – d ) Presenilin-deficient MEF cells (PS−/−) were transduced with human BCMA (PS−/− BCMA) and then with wild-type PS1 (PS−/− BCMA PS1) or with a catalytically inactive mutant (PS−/− BCMA PS1-D385A). BCMA surface expression ( a , b ) and sBCMA release ( d ) were determined. In a , a representative experiment is shown; in b , d , mean±s.e.m. of four independent experiments is given (respectively, P =0.0313 and P =0.0033, paired t -test). ( c ) Cells used in a , b , d were analysed by immunoblotting for expression of full-length PS1 (PS1 holo ), for autoendoproteolysis of PS1 generating a C-terminal fragment (PS1 CTF ) reflecting an active state of the γ-secretase, for maturation of nicastrin (NCT) and for full-length BCMA (mBCMA).

Article Snippet: Supernatants generated by HEK293T cells that had been transfected with full-length BCMA (OriGene Technologies, Inc., Rockville) or an empty control vector and therefore either contained sBCMA or did not, were added at a final sBCMA concentration of 200 ng ml −1 and 400 ng ml −1 .

Techniques: Transduction, Mutagenesis, Expressing, Western Blot

Journal: Nature Communications

Article Title: γ-secretase directly sheds the survival receptor BCMA from plasma cells

doi: 10.1038/ncomms8333

Figure Lengend Snippet: ( a , b ) HeLa cells were transfected with plasmids coding for full-length human BCMA or BCMA with an N-terminal FLAG and then cultured with increasing amounts of the γ-secretase inhibitor DAPT (0.02, 0.1 and 0.5 μM). Twenty-four hours after transfection supernatants were harvested and the released sBCMA was analysed using ELISA. In ( a ), ELISA wells were coated with anti-BCMA, and in ( b ) with anti-FLAG or a control IgG (anti-myelin oligodendrocyte glycoprotein (MOG) 8.18 C5), both were developed with anti-BCMA. Schemes of the ELISAs are shown on the right. Combined data of two independent experiments (mean±s.e.m.). ( c – e ) Human BCMA wild type (wt) or BCMA–BCMA with a doubled extracellular domain of BCMA were transfected into HEK293T cells. ( c , d ) Surface expression of BCMA was determined in the absence or presence of the γ-secretase inhibitor DAPT (1 μM). ( d ) The combined data of three experiments ( P =0.0049, ** P <0.01, unpaired t -test). ( e ) The effect of DAPT on the released sBCMA after transfection with BCMA wt or BCMA–BCMA (mean±s.e.m. of three experiments), P =0.0081, ** P <0.01, unpaired t -test.

Article Snippet: Supernatants generated by HEK293T cells that had been transfected with full-length BCMA (OriGene Technologies, Inc., Rockville) or an empty control vector and therefore either contained sBCMA or did not, were added at a final sBCMA concentration of 200 ng ml −1 and 400 ng ml −1 .

Techniques: Transfection, Cell Culture, Enzyme-linked Immunosorbent Assay, Control, Expressing

Journal: Nature Communications

Article Title: γ-secretase directly sheds the survival receptor BCMA from plasma cells

doi: 10.1038/ncomms8333

Figure Lengend Snippet: ( a , b ) HEK293T cells were transfected with full-length human BCMA or an empty vector. DAPT, APRIL ( a ) or BAFF ( b ) were added, and NF-κB activation was determined. Combined data of three independent experiments (mean±s.e.m., * P <0.05, paired t -test).

Article Snippet: Supernatants generated by HEK293T cells that had been transfected with full-length BCMA (OriGene Technologies, Inc., Rockville) or an empty control vector and therefore either contained sBCMA or did not, were added at a final sBCMA concentration of 200 ng ml −1 and 400 ng ml −1 .

Techniques: Transfection, Plasmid Preparation, Activation Assay

Journal: Nature Communications

Article Title: γ-secretase directly sheds the survival receptor BCMA from plasma cells

doi: 10.1038/ncomms8333

Figure Lengend Snippet: ( a ) A scheme of the ELISA is shown on the left; it detects BCMA–APRIL–FLAG (left panel) or BCMA–BAFF–FLAG (right panel) complexes, but neither BCMA nor APRIL–FLAG nor BAFF–FLAG alone alone (* P <0.05, paired t -test). sBCMA was derived from the supernatant of plasmacytoma cultured under serum-free conditions. Combined data of three independent experiments (mean±s.e.m.). ( b ) HEK293T cells were transfected with human BCMA and activated with APRIL (left panel) or BAFF (right panel). sBCMA (50 and 200 ng ml −1 ) was applied as indicated. sBCMA and control supernatant were obtained as mentioned above. BCMA-Fc (50 and 200 ng ml −1 ) was used as a positive control. Combined data of three independent experiments (mean±s.e.m., * P <0.05; ** P <0.01 paired test). ( c ) Murine B cells were activated via anti-IgM and cultured for 2 days with APRIL in the presence or absence of sBCMA (200 and 400 ng ml −1 ). APRIL-induced survival was calculated as described in the Methods section. sBCMA was obtained from supernatant from HEK293T cells transfected with full-length BCMA (black bars). Control supernatant was obtained after transfection with an empty vector (white bars). sBCMA significantly inhibited APRIL-mediated survival (*** P <0.001 and ** P <0.01, paired t -test). Combined data of six independent experiments (mean±s.e.m.). ( d ) Illustration of the consequences of sBCMA shedding by γ-secretase: left: an active γ-secretase cleaves mBCMA. This reduces the number of membrane-bound BCMA molecules and releases sBCMA, which binds its ligand APRIL functioning as a decoy. Right: γ-secretase inhibitors (GSIs) result in elevated mBCMA on the surface and increased APRIL-mediated activation and survival.

Article Snippet: Supernatants generated by HEK293T cells that had been transfected with full-length BCMA (OriGene Technologies, Inc., Rockville) or an empty control vector and therefore either contained sBCMA or did not, were added at a final sBCMA concentration of 200 ng ml −1 and 400 ng ml −1 .

Techniques: Enzyme-linked Immunosorbent Assay, Derivative Assay, Cell Culture, Transfection, Control, Positive Control, Plasmid Preparation, Membrane, Activation Assay

Journal: Nature Communications

Article Title: γ-secretase directly sheds the survival receptor BCMA from plasma cells

doi: 10.1038/ncomms8333

Figure Lengend Snippet: ( a ) Immunized (OVA–LPS in alum) C57/BL6 mice were treated with the γ-secretase inhibitor LY-411575-I or vehicle, and the surface display of BCMA in splenocytes was measured using flow cytometry 1 day later. BCMA expression on gated B220 + CD138 + cells is shown, a representative example (left) and compiled data from all 17 analysed animals (mean, *** P <0.001, unpaired t -test; right). The black symbols on the right indicate the samples shown on the left. Closed histograms indicate isotype controls. ( b ) NZB/W mice pretreated with BrdU received the γ-secretase inhibitor LY-411575-I (red) or vehicle (blue) for 1 day. Surface expression of BCMA on all CD138 + plasma cells (PC) and the BrdU + and BrdU − PC subgroups in the spleen and bone marrow (BM) was determined using flow cytometry. ( c – e ) Seven-day treatment of NZB/W mice with LY-411575-I. ( c ) BCMA surface expression in the spleen and BM on B220, and BrdU + and BrdU − plasma cells was determined. ( d ) Absolute number of plasma cells, BrdU + and BrdU − plasma cells in the spleen and BM. ( e ) Frequency (% of all cells in the organ) of plasma cells in the spleen and BM. Compiled data from 10 analysed animals per group (mean; * P <0.05; ** P <0.01; *** P <0.001; **** P <0.0001, unpaired t -test).

Article Snippet: Supernatants generated by HEK293T cells that had been transfected with full-length BCMA (OriGene Technologies, Inc., Rockville) or an empty control vector and therefore either contained sBCMA or did not, were added at a final sBCMA concentration of 200 ng ml −1 and 400 ng ml −1 .

Techniques: Flow Cytometry, Expressing, Clinical Proteomics

Journal: EMBO Molecular Medicine

Article Title: B cell lineage reconstitution underlies CAR-T cell therapeutic efficacy in patients with refractory myasthenia gravis

doi: 10.1038/s44321-024-00043-z

Figure Lengend Snippet: ( A ) A schematic overview of the time points at which patients receive different treatments before CAR-T infusion. # Patient MG-1 was treated with IVIG 2 g/Kg + intravenous pulse steroid 500 mg* 3days for myasthenia crisis. ( B ) A schematic overview of CAR-T treatment procedure. CAR T-cell kinetics are shown by the CAR copies per μg genomic DNA at serial time points post infusion detected by droplet digital PCR. ( C ) Representative plots showing FACS analysis stained for CAR-T cells with FITC-labeled human BCMA Fc tag protein and APC/Cy7 anti-human CD3 antibody in patient MG-1 at day 10 after CAR T-cell infusion. CAR T-cell percentage in circulating CD3 + T lymphocytes at serial time points after treatment. ( D ) Timelines of patients with cytopenia of grade 3 or higher at baseline and indicated time points after CAR T-cell infusion. BL baseline. Kinetic changes in numbers of circulating total white blood cells, neutrophils, monocytes and platelets. ( E ) Heatmap depicting protein levels of inflammatory mediators in blood following CAR T-cell infusion. Interleukin IL, TNF tumor necrosis factor, IFN interferon, CRP C-reactive protein, PCT procalcitonin. Average levels are normalized from the baseline. .

Article Snippet: Website links for the antibodies used in the flow cytometry are following: PerCP/Cyanine5.5 anti-human CD45 Antibody (Biolegend, 304028): https://www.biolegend.com/en-us/products/percp-cyanine5-5-anti-human-cd45-antibody-4240 ; FITC anti-human CD3 antibody (BD Biosciences, 561802): https://www.bdbiosciences.com/zh-cn/products/reagents/flow-cytometry-reagents/research-reagents/single-color-antibodies-ruo/fitc-mouse-anti-human-cd3.561802 ; PE/Cyanine7 anti-Human CD4 (BD Biosciences, 560649): https://www.bdbiosciences.com/zh-cn/products/reagents/flow-cytometry-reagents/research-reagents/single-color-antibodies-ruo/pe-cy-7-mouse-anti-human-cd4.560649 ; APC/Cyanine7 anti-Human CD8 (BD Biosciences, 557834): https://www.bdbiosciences.com/zh-cn/products/reagents/flow-cytometry-reagents/research-reagents/single-color-antibodies-ruo/apc-cy-7-mouse-anti-human-cd8.557834 ; APC anti-human CD19 Antibody (Biolegend, 302212): https://www.biolegend.com/en-us/products/apc-anti-human-cd19-antibody-715 ; PE anti-human CD16 Antibody (Biolegend, 302056): https://www.biolegend.com/en-us/products/pe-anti-human-cd16-antibody-569 ; PE anti-human CD56 Antibody (Biolegend, 318306): https://www.biolegend.com/en-us/products/pe-anti-human-cd56-ncam-antibody-3796 ; FITC anti-Human CD38 (BD Biosciences, 567147): https://www.bdbiosciences.com/en-us/products/reagents/flow-cytometry-reagents/research-reagents/single-color-antibodies-ruo/fitc-mouse-anti-human-cd38.567147 ; PerCP/Cyanine5.5 anti-Human CD27 (BD Biosciences, 560612): https://www.bdbiosciences.com/zh-cn/products/reagents/flow-cytometry-reagents/research-reagents/single-color-antibodies-ruo/percp-cy-5-5-mouse-anti-human-cd27.560612 ; PerCP anti-Human CD45 (BD Biosciences, 347464): https://www.bdbiosciences.com/zh-cn/products/reagents/flow-cytometry-reagents/clinical-discovery-research/single-color-antibodies-ruo-gmp/percp-mouse-anti-human-cd45.347464 ; APC/Cyanine7 anti-human CD3 Antibody (Biolegend, 344818): https://www.biolegend.com/en-us/products/apc-cyanine7-anti-human-cd3-antibody-6940 ; FITC-labeled human BCMA Fc tag protein (Acrobiosystems, BCA-HF254): https://www.acrobiosystems.cn/P875-FITC-Labeled_Human_BCMA_%7C_TNFRSF17_Protein_Fc_Tag.html .

Techniques: Digital PCR, Staining, Labeling

Journal: Journal of autoimmunity

Article Title: CAR-T cell targeting three receptors on autoreactive B cells for systemic lupus erythematosus therapy.

doi: 10.1016/j.jaut.2025.103369

Figure Lengend Snippet: Fig. 1. B cells populations, BAFF receptors expression, In-vitro B cells specific cytotoxicity, and the cytokine release of BAFF CAR-T cells. A) Percentage of B cell subset populations in healthy (N = 3) vs SLE patient samples (N = 6). The average percentages from control and SLE patients are plotted as pie chart, and the gating strategies are given in the Supplementary Fig. S2A. B) The BAFF receptors expression in the healthy donor (N = 8) and active SLE patient peripheral blood monocytic cells (PBMCs) gated on the lymphocytes (N = 13). C) Percentage of the BAFF CAR positive T cells after transfection in healthy vs SLE patients (N = 3). D) In-vitro cytotoxicity of autologous control-T and BAFF CAR-T cells on healthy donor B cells and, E) SLE patient B cells, co-cultured at the E:T ratio of 1:1, 3:1, and 5:1 for 48 h (N = 3). Also, the effect of control-T and BAFF CAR-T cells from healthy donors and SLE on Jeko-1, RPMI-8226, and Jeko-KO B cell lines at 3:1 ratio (N = 3). F) Representative 2D scatter plots showing the CD19 vs BAFFr/BCMA/TACI/IgM populations after co- culturing the UT/CD19 CAR-T/BAFF-CAR-T cells with the active SLE patient PBMCs at E:T ratio of 5:1 for 24 h gated on lymphocytes. G) Percentage of CD19+ BAFFr+, CD19+ IgM+, and CD19−IgM+, and the CD19−BCMA+ populations after co-culture (N = 5). H) Inflammatory cytokines, activation/degranulation enzyme levels in the supernatant after co-culturing the PBMCs with UT/CD19-CAR-T/BAFF CAR-T cells for 24 h at E:T ratio of 5:1 (N = 4). I) In-vitro cytotoxicity of UT, CD19 CAR-T and BAFF CAR-T cells on CD138+ plasma B cells from multiple myeloma patient samples after co-culture for 24 h at E:T ratios of 5:1 and 10:1 (N = 3). The p value < 0.05 is considered as statistically significant. The student t-test was employed to compare figure B, C, G, and two-way ANOVA with Tukey’s test was used for the analysis of the figures A, D, E, H and I. P < 0.05 = *, P < 0.01 = **, P < 0.001 = ***.

Article Snippet: The plasma levels of total IgM (ab207620-abcam), total IgG (ab151276-abcam), urine albumin (ab2076201-abcam), autoantibodies to IgG anti-dsDNA (CSB-E11194M-Cusabio), Anti-ANA (total-Ig) (EKF58166-Biomatik), and soluble forms of BAFFr (EMTNFRSF13CThemofisher Scientific), BCMA (DY593- R&D Systems), and TACI (DY1041- R&D systems) were measured by the sandwich ELISA method according to the manufactures instructions given in the kits.

Techniques: Expressing, In Vitro, Control, Transfection, Cell Culture, Co-Culture Assay, Activation Assay, Clinical Proteomics

Journal: Journal of Hematology & Oncology

Article Title: A bispecific CAR-T cell therapy targeting BCMA and CD38 in relapsed or refractory multiple myeloma

doi: 10.1186/s13045-021-01170-7

Figure Lengend Snippet: Preclinical evaluation of BM38 CAR-Ts. a Schematic structure of single-target BCMA CAR, CD38 CAR, bispecific 38BM CAR and BM38 CAR. All the CARs contained a granulocyte–macrophage colony-stimulating factor signal peptide (GM-CSF SP), a CD8 hinge and transmembrane domain, a 4-1BB costimulatory domain and a CD3ζ signaling domain. b CAR expression on lentivirus-transduced T cells and CD38 expression on CAR-Ts. Histograms are representative of 3 independent experiments. NT, nontransduced T. NT blank, NT without antibody staining. NT parallel, NT with antibody staining. c Phenotypic profiles of the final CAR-T products and NT cells. Differentiation phenotypes are depicted for naïve (CD45RA + CD62L + ), central memory (CM) (CD45RA − CD62L + ), effector memory (EM) (CD45RA − CD62L − ) and effector (CD45RA + CD62L − ) cells. n = 3, mean ± standard error of mean (SEM). Statistical analysis was performed using one-way ANOVA and subsequent multiple comparisons with BM38 CAR-Ts. *** P < 0.001; ns: not significant. d Expansion curves of the four CAR-Ts and NT cells after lentiviral transduction. n = 5, mean ± SEM. Repeated measures one-way ANOVA was used, ns: not significant. e Cytotoxicity of the four CAR-Ts and NT cells to target cells at an effector: target (E:T) ratio of 1:1, 5:1 and 10:1. n = 4, mean ± SEM. Dunnett’s multiple comparisons test was used at every E:T ratio with BM38 CAR-Ts as the control. * P < 0.05; ** P < 0.01; *** P < 0.001; ns: not significant. f Production of interferon γ (IFNγ) at an E:T ratio of 1:1. n = 3, mean ± SEM. Dunnett’s multiple comparisons test was used with BM38 CAR-Ts as control. ** P < 0.01; *** P < 0.001; ns: not significant. g Luciferase live imaging of MM.1s xenograft mice on day 0, 7, 14 and 23 after infusion of 3.0 × 10 6 NT cells, BCMA CAR-Ts, 38BM CAR-Ts or BM38 CAR-Ts. h Kaplan–Meier survival plot of MM xenograft mice. The log-rank test was used

Article Snippet: All the cell lines were authenticated for CD38 (anti-CD38-APC, 555335; BD Biosciences [BD], USA) and BCMA (anti-BCMA-PE, 130-119-147; Miltenyi Biotec, USA) expression by flow cytometry, and cultured in RPMI 1640 medium (Gibco, USA) containing 10% fetal bovine serum (NQBB, China).

Techniques: Expressing, Staining, Transduction, Control, Luciferase, Imaging

Journal: Journal of Hematology & Oncology

Article Title: A bispecific CAR-T cell therapy targeting BCMA and CD38 in relapsed or refractory multiple myeloma

doi: 10.1186/s13045-021-01170-7

Figure Lengend Snippet: Clinical responses mediated of BM38 CAR-Ts. a Swimmer plot for the 23 patients treated in the study. Two patients were enrolled in the two low-dose groups for the consideration of risk–benefit trade-off. b Immunohistochemical staining of patient 13’s right parailiac mass before treatment, showing involvement of MM cells and positive expression of BCMA and CD38. c Computed tomography scans of patient 13 showing a large right parailiac plasmacytoma at enrollment that was partially eliminated in month 3 and completely disappeared in month 5. d Changes of serum M protein in patient 13 during BM38 CAR-T treatment. e BCMA and CD38 expression on MM cells in patient 15 and 20 at baseline. Representative staining and gating of MM cells are shown in Additional file : Fig. S6

Article Snippet: All the cell lines were authenticated for CD38 (anti-CD38-APC, 555335; BD Biosciences [BD], USA) and BCMA (anti-BCMA-PE, 130-119-147; Miltenyi Biotec, USA) expression by flow cytometry, and cultured in RPMI 1640 medium (Gibco, USA) containing 10% fetal bovine serum (NQBB, China).

Techniques: Immunohistochemical staining, Staining, Expressing, Computed Tomography

Journal: Journal of Hematology & Oncology

Article Title: A bispecific CAR-T cell therapy targeting BCMA and CD38 in relapsed or refractory multiple myeloma

doi: 10.1186/s13045-021-01170-7

Figure Lengend Snippet: Predictive docking patterns of BM38 CAR to MM cells. a Hypothetical structure of the anti-BCMA scFv and anti-CD38 scFv joined with an (EAAAK) 3 linker (not shown). b Most favorable docking models of the anti-BCMA scFv with 51 amino acid residues of the extracellular domain of BCMA (2kn1.pdb); c Most favorable docking models of the anti-CD38 scFv with 257 amino acid residues of the extracellular domain of CD38 (1yh3.pdb); d Dual docking of BM38 CAR with BCMA and CD38. e Theoretical single combination pattern of the anti-CD38 scFv and CD38 on MM cells. f Theoretical single combination pattern of the anti-BCMA scFv and BCMA on MM cells. g Theoretical double-binding pattern of the bispecific BM38 CAR to BCMA and CD38 on MM cells. h–i The CD38 extracellular domain contains 257 amino acids and the BCMA extracellular chain consists of only 54 amino acids. The anti-BCMA scFv and anti-CD38 scFv contain 246 and 249 amino acids, respectively. Theoretically, CD38 binding might assist the anti-BCMA scFv in binding to BCMA on myeloma cells, and BCMA coalescence would reversely strengthen CD38 binding

Article Snippet: All the cell lines were authenticated for CD38 (anti-CD38-APC, 555335; BD Biosciences [BD], USA) and BCMA (anti-BCMA-PE, 130-119-147; Miltenyi Biotec, USA) expression by flow cytometry, and cultured in RPMI 1640 medium (Gibco, USA) containing 10% fetal bovine serum (NQBB, China).

Techniques: Binding Assay