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C. Francisco, J. V. Usa-), N. Ravetch, J. Leusen-), and R. Good, The Netherlands) for mice, p.769

D. Voehringer, Erlangen, Germany) for antibodies. Cl 2 MDP was a gift 771

D. Of-roche and . Gmbh, This work was supported by the Institut Pasteur, p.772

. National-de-la-santé-et-de-la-recherche-médicale, the European Research Council 773 (ERC)?Seventh Frame-work Program (ERC-2013-CoG 616050), the Société Française 774 d'Allergologie (SFA; Soutien de la Recherche en Allergologie) and the Balsan company. H.B. is 775 supported by a fellowship from the University Pierre et Marie Curie, p.776

R. Scientifique, (. R. Cnrs-), and S. J. , are supported by NIH/NIAMS grant R01 779