Prevailing dogma holds that cell–cell communication through Notch ligands and receptors determines binary cell fate decisions during progenitor cell divisions, with differentiated lineages remaining fixed1. Mucociliary clearance2,3 in mammalian respiratory airways depends on secretory cells (club and goblet) and ciliated cells to produce and transport mucus. During development or repair, the closely related Jagged ligands (JAG1 and JAG2) induce Notch signalling to determine the fate of these lineages as they descend from a common proliferating progenitor4,5,6,7,8. In contrast to such situations in which cell fate decisions are made in rapidly dividing populations9,10, cells of the homeostatic adult airway epithelium are long-lived11,12,13, and little is known about the role of active Notch signalling under such conditions. To disrupt Jagged signalling acutely in adult mammals, here we generate antibody antagonists that selectively target each Jagged paralogue, and determine a crystal structure that explains selectivity. We show that acute Jagged blockade induces a rapid and near-complete loss of club cells, with a concomitant gain in ciliated cells, under homeostatic conditions without increased cell death or division. Fate analyses demonstrate a direct conversion of club cells to ciliated cells without proliferation, meeting a conservative definition of direct transdifferentiation14. Jagged inhibition also reversed goblet cell metaplasia in a preclinical asthma model, providing a therapeutic foundation15. Our discovery that Jagged antagonism relieves a blockade of cell-to-cell conversion unveils unexpected plasticity, and establishes a model for Notch regulation of transdifferentiation.
Protein Data Bank
Atomic coordinates and structure factors for the human JAG1–Fab complex have been deposited in the Protein Data Bank under accession code 5BO1
The authors thank E. Jackson and R. Pattni for work generating the Scgb1a1-ERT2GNE mice; L.Nguyen, L. Orellana, P. Grigg and the Genentech Transgenic Technology Laboratories and Research Support Facility for technical assistance with mouse strains and colonies; F. Chu, L. Rangell, S. Chalasani, C. Jones III and C. Espiritu for cell staining; A. Ertürk, C. Chalouni, S. Gierke, M. Gonzalez-Edick and the Genentech Center for Advanced Light Microscopy (CALM) for imaging; C. K. Poon for cytokine measurements; S. P. Tsai and M. Dostalek for pharmacokinetic analyses; T. Hagenbeek for help with the immune cell studies. Use of the Stanford Synchrotron Radiation Lightsource SSRL 12-12 at Stanford Linear Accelerator Center National Accelerator Laboratory is supported by the US Department of Energy (DOE), DOE Office of Biological and Environmental Research, National Institutes of Health, and National Institute of General Medical Sciences. The contents of this publication are the responsibility of the authors and do not necessarily represent the views of NIH or NIGMS.
Extended data figures
The video shows single tracheal cells from Scgb1a1-CreERT2GNE /Rosa26-lsl-tdTomato mice induced with four doses of 200mg kg-1 tamoxifen and treated with a single dose of control antibody for six days, one week after the last Tamoxifen injection. CC10-traced cells appear white. At least two ciliated cells (control, not labeled white and, thus, not converted from club cells following JAG blockade) with motile cilia are visible (right side). A tdTomato-positive (white) club cell (no cilia) is visible on the left.
The video shows single tracheal cells from Scgb1a1-CreERT2GNE /Rosa26-lsl-tdTomato mice induced with four doses of 200mg kg-1 Tamoxifen and treated with a single dose of with anti-JAG1.b70 plus anti-JAG2.b33 for six days, one week after the last Tamoxifen injection. At least two ciliated cells (control, not labeled white and, thus, not converted from club cells following JAG blockade) with motile cilia are visible (middle). A tdTomato-positive cell (white), marking a daughter cell derived from the club cell lineage, has beating cilia (middle), supporting the notion that an induced ciliated cell functions normally, similar to the control (unlabelled) ciliated cells.