Therapy of sIgM+/+ mice cause an altered B-2 cell differentiation
Therapy of sIgM+/+ mice bring about an altered B-2 cell differentiation profile, characterized by a robust reduction of MZ B cells already immediately after 2-weeks remedy and a proportional boost of FO B cells thatScientific RepoRts | 7: 3540 | DOI:10.1038/s41598-017-03688-www.nature/scientificreports/Figure 1. sIgM deficiency final results in altered splenic B cell improvement. (a) Representative flow cytometry plots and bar graphs show absolute numbers of FO/T2 (blue), MZ (purple), CD21+ CD23- B cells (red), T1 (green) and NF (grey) cells (defined in Fig. S2) of sIgM+/+ (light colored bars) and sIgM-/- (dark colored bars) mice. (b) Representative flow cytometry plots and dot plots show the frequencies of MZ (purple) and FO/T2 (blue) B cells of sIgM+/+ () and sIgM-/- () mice treated with automobile and sIgM-/- () treated with polyclonal IgM (n = 4sirtuininhibitor mice per group). (c) Absolute numbers of splenic B220highCD93-CD21+ CD23- B cells and (d) Blimp-1 mean fluorescence intensity (MFI) in CD21+ CD23- B cells of sIgM+/+ (light red bar) and sIgM-/- (dark red bar) mice analyzed by flow cytometry. (e,f) Representative flow cytometry plots show the percentages of either kappa or lambda light chain optimistic and bars represent the imply kappa/lambda light chain ratio of (e) B220+CD43- splenic cells and (f) mature (B220high CD43-) and immature (B220low CD43-) bone DKK-1 Protein Source marrow cells within cells that express BCR. (a,c ) Information shown are from a single representative experiment of at the very least two to three independent experiments with 5sirtuininhibitor mice per group. All results show mean sirtuininhibitorSEM. P sirtuininhibitor 0.05, P sirtuininhibitor 0.01, P sirtuininhibitor 0.001, P sirtuininhibitor 0.0001 (Mann-Whitney or unpaired t test or One-Way Anova test followed by Tukey’s test).became evident after 3-weeks treatment (Fig. 3a,b). These information recommend that lowering BCR signaling limits MZ and promotes FO B cell improvement also in sIgM+/+ mice. Due to the fact sIgM recognize unique forms of self-antigens such as cellular debris and apoptotic cells10, 11, we investigated if sIgM antibodies modulate BCR signaling in a self-antigen mediated manner. For this purpose, we employed the model of MD4 transgenic mice that express BCRs directed against hen egg lysozyme (HEL). MD4 B cells produce HEL-specific IgM antibodies (Fig. 4a), even though they lack the capability to class switch to other immunoglobulin isotypes18. Stimulation of purified MD4 B-2 cells with HEL inside the presence of plasma from either WT (grey bars) or RAG1-/- (purple bars) mice resulted inside a robust BCR activation as measured by increased levels of pBtk (Fig. 4b). In contrast, HEL stimulation in presence of plasma from MD4 mice (blue bars) failed to IL-7 Protein Gene ID trigger BCR signaling (Fig. 4b). These data suggest that HEL-specific IgM antibodies present in MD4 plasma prevent self-antigen induced BCR activation. To investigate this further, we depleted HEL-specific IgM antibodies fromScientific RepoRts | 7: 3540 | DOI:10.1038/s41598-017-03688-Antigen-specific secreted IgM dampen self-antigen induced BCR signaling.www.nature/scientificreports/Figure two. sIgM deficiency benefits in elevated B cell receptor signaling in vivo. Representative flow cytometry plots and bar graphs show (a ) the mean fluorescence intensity (MFI) for pSyk, pBtk levels and Nurr77-GFP expression in FO/T2 (blue), MZ (purple), CD21+ CD23- (red), T1 (green) and NF (grey) B cells (as defined in Fig. S2) of sIgM+/+ or Nur77-GFP/sIgM+/+ (light colored bar) and sIgM-/-.
