Abstract
B cell receptor (BCR) engagement induces naive B cells to differentiate and perform critical immune-regulatory functions. Acquisition of functional specificity requires that a cell survive, enter the cell cycle, and proliferate. We establish that quantitatively distinct Ca2+ signals triggered by variations in the extent of BCR engagement dynamically regulate these transitions by controlling nuclear factor κB (NF-κB), NFAT, and mTORC1 activity. Weak BCR engagement induces apoptosis by failing to activate NF-κB-driven anti-apoptotic gene expression. Stronger signals that trigger more robust Ca2+ signals promote NF-κB-dependent survival and NFAT-, mTORC1-, and c-Myc-dependent cell-cycle entry and proliferation. Finally, we establish that CD40 or TLR9 costimulation circumvents these Ca2+-regulated checkpoints of B cell activation and proliferation. As altered BCR signaling is linked to autoimmunity and B cell malignancies, these results have important implications for understanding the pathogenesis of aberrant B cell activation and differentiation and therapeutic approaches to target these responses.
Original language | English |
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Article number | 107474 |
Journal | Cell Reports |
Volume | 31 |
Issue number | 2 |
DOIs | |
State | Published - 14 Apr 2020 |
Bibliographical note
Funding Information:We thank Dr. Hsiou-chi Liou (Cornell University) for providing the Rel −/− mice, Dr. Michael Atchison (University of Pennsylvania) and Dr. Montserrat Anguera (University of Pennsylvania) for providing mb1-cre mice, and Dr. Michael Karin (UCSD) for providing IKK2 fl/fl mice. We thank A.A.D., L.C., A.P., and M.C.A. for assisting with methodology and supplying valuable resources. These studies were funded by the NIH (grants R56AI125415 and RO1AI60921 to B.D.F., grants R01HL096642 and R01AR066567 to M.J.M., and AI128530 to I.E.B.).
Funding Information:
We thank Dr. Hsiou-chi Liou (Cornell University) for providing the Rel?/? mice, Dr. Michael Atchison (University of Pennsylvania) and Dr. Montserrat Anguera (University of Pennsylvania) for providing mb1-cre mice, and Dr. Michael Karin (UCSD) for providing IKK2fl/fl mice. We thank A.A.D. L.C. A.P. and M.C.A. for assisting with methodology and supplying valuable resources. These studies were funded by the NIH (grants R56AI125415 and RO1AI60921 to B.D.F. grants R01HL096642 and R01AR066567 to M.J.M. and AI128530 to I.E.B.). Conceptualization, C.T.B. and B.D.F.; Methodology, C.T.B. and B.D.F.; Investigation, C.T.B. X.L. A.M. S.N. and B.D.F.; Writing ? Original Draft, C.T.B. M.J.M. and B.D.F.; Writing ? Review & Editing, C.T.B, Y.H.C. I.E.B. M.P.C. C.J.L. and B.D.F.; Funding Acquisition, B.D.F. and M.J.M.; Resources, B.D.F. Y.H.C. I.E.B. M.P.C. C.J.L. and M.J.M.; Supervision, B.D.F. The authors declare no competing interests.
Publisher Copyright:
© 2020 The Authors
Keywords
- Bcl-xL
- CD40
- NFAT
- Orai1
- STIM1
- apoptosis
- c-Myc
- c-Rel
- mTORC1
- nuclear factor kappa B
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology (all)