Journal article

Authors list: Goretzki, Alexandra; Lin, Yen-Ju; Meier, Clara; Dorn, Britta; Wolfheimer, Sonja; Jamin, Annette; Schott, Maike; Wangorsch, Andrea; Vieths, Stefan; Jakob, Thilo; Scheurer, Stephan; Schuelke, Stefan

Publication year: 2023

Pages: 663-681

Journal: Allergy

Volume number: 78

Issue number: 3

ISSN: 0105-4538

eISSN: 1398-9995

Open access status: Hybrid

DOI Link: https://doi.org/10.1111/all.15542

Publisher: Wiley

Abstract: 
Background The experimental fusion protein rFlaA:Betv1 was shown to efficiently suppress allergen-specific sensitization in mice. However, the detailed mechanism of rFlaA:Betv1-mediated immune modulation is not fully understood. In this study, we investigated the effect of rFlaA:Betv1 on naive murine B cells. Methods Immune modulating capacity of rFlaA:Betv1 was screened in IL-10 reporter mice. B cells were isolated from spleens of naive C57Bl/6, TLR5(-/-), or MyD88(-/-) mice, stimulated with rFlaA:Betv1 and controls, and monitored for the expression of the regulatory B cell markers CD1d, CD24, CD38, and surface IgM by flow cytometry. Secreted cytokines, antibodies, and reactivity of the induced antibodies were investigated by ELISA and intracellular flow cytometry. Suppressive capacity of rFlaA:Betv1-stimulated B cells was tested in mDC:CD4(+) T cell:B cell triple cultures. Results Upon in vivo application of rFlaA:Betv1 into IL-10-GFP reporter mice, CD19(+) B cells were shown to produce anti-inflammatory IL-10, suggesting B cells to contribute to the immune-modulatory properties of rFlaA:Betv1. rFlaA:Betv1-induced IL-10 secretion was confirmed in human B cells isolated from buffy coats. In vitro stimulation of naive murine B cells with rFlaA:Betv1 resulted in an mTOR- and MyD88-dependent production of IL-10 and rFlaA:Betv1 induced Bet v 1-reactive IgG production, which was not observed for IgA. rFlaA:Betv1-stimulated B cells formed a CD19(+)CD24(+)CD1d(+)IgM(+)CD38(+) Breg subpopulation capable of suppressing Bet v 1-induced TH2 cytokine secretion in vitro. Conclusion rFlaA:Betv1 can act as a thymus-independent B cell antigen, stimulating the mTOR- and MyD88-dependent differentiation of B cells displaying a regulatory phenotype, IL-10 secretion, antigen-binding antibody production, and a suppressive capacity in vitro.

Harvard Citation style: Goretzki, A., Lin, Y., Meier, C., Dorn, B., Wolfheimer, S., Jamin, A., et al. (2023) Stimulation of naive B cells with a fusion protein consisting of FlaA and Bet v 1 induces regulatory B cells ex vivo, Allergy, 78(3), pp. 663-681. https://doi.org/10.1111/all.15542

APA Citation style: Goretzki, A., Lin, Y., Meier, C., Dorn, B., Wolfheimer, S., Jamin, A., Schott, M., Wangorsch, A., Vieths, S., Jakob, T., Scheurer, S., & Schuelke, S. (2023). Stimulation of naive B cells with a fusion protein consisting of FlaA and Bet v 1 induces regulatory B cells ex vivo. Allergy. 78(3), 663-681. https://doi.org/10.1111/all.15542