Notch2 and B cell antigen receptor (BCR) signaling determine whether transitional B cells become marginal zone B (MZB) or follicular B (FoB) cells in the spleen, but it is unknown how these pathways are related. We generated Taok3 -/- mice, lacking the serine/threonine kinase Taok3, and found cell-intrinsic defects in the development of MZB but not FoB cells. Type 1 transitional (T1) B cells required Taok3 to rapidly respond to ligation by the Notch ligand Delta-like 1. BCR ligation by endogenous or exogenous ligands induced the surface expression of the metalloproteinase ADAM10 on T1 B cells in a Taok3-dependent manner. T1 B cells expressing surface ADAM10 were committed to becoming MZB cells in vivo, whereas T1 B cells lacking expression of ADAM10 were not. Thus, during positive selection in the spleen, BCR signaling causes immature T1 B cells to become receptive to Notch ligands via Taok3-mediated surface expression of ADAM10.

doi.org/10.1038/ni.3657, hdl.handle.net/1765/108056
Nature Immunology
Department of Pulmonology

Hammad, H., Vanderkerken, M. (Matthias), Pouliot, P., Deswarte, K., Toussaint, W., Vergote, K., Vandersarren, L. (Lana), Janssens, S., Ramou, I. (Ioanna), Savvides, S.N. (Savvas N.), Haigh, K., Hendriks, R., Kopf, M. (Manfred), Craessaerts, K. (Katleen), de Strooper, B., Kearney, J.F. (John F.), Conrad, D.H. (Daniel H.)& Lambrecht, B. (2017). Transitional B cells commit to marginal zone B cell fate by Taok3-mediated surface expression of ADAM10. Nature Immunology, 18(3), 313–320.https://doi.org/10.1038/ni.3657