C. , We used two different metal-conjugated antibody cocktails (all antibodies were from Fluidigm, unless otherwise indicated, in which case they were conjugated in-house). The first experiment was performed with Rutenium Red (R&D Systems), Avanti-Lipid (R&D Systems), anti-alphaSMA-141Pr (clone IA4), the Hyperion Imaging System (Fluidigm) for data acquisition, pp.123-148, 2017.

M. Biotec, clone HI100), CD14-156Gd (clone HCD14), pp.13-157

. R&d-biotechne, CD324/E-cadherin-158Gd (clone 24 E10), pp.4-161

. Origene, Foxp3-162Dy (clone 259/C7), pp.6-163

, IL-21-164Dy (polycolonal; Novus Bio), pp.2-166

. Neobiotech, Thermo Fisher Scientific), CD279/PD-1-175Lu (clone EH12.2H7), histoneH3-176Yb (clone D1H2), and DNA-191/193Ir. We excluded from analysis several markers showing low staining: CD123, CD1c, CD44, CTLA4, CXCR5, and collagen14. The second series was performed with anti-alphaSMA-141Pr (clone IA4), CD303/BDCA2-147Sm (clone 201A), clone UCHT1), CD185/CXCR5-171Yb (clone 51505), pp.11-149

M. Biotec, CD370/Clec9A-161Dy (clone 8F9), Bcl6-163Dy (clone K112-91), pp.68-171

M. Biotec, , pp.3-170

, CD56-176Yb (clone HCD56), and DNA-191/193Ir. The second series was subsequently incubated with Neutravidin-173Yb. We excluded from analysis several markers showing low staining: CD303, ICOS, CD11b, CD1c, pp.5-56

, Institut Curie (CIC IGR-Curie 1428), the European Research Council (2013-AdG N°340046 DCBIOX to S. Amigorena)

. Amigorena, Cancéropôle Ile-de-France, the SESAME program from Région Ile-de-France, and the Site de Recherche Intégrée sur le Cancer-Curie program (Site de Recherche Intégrée sur le Cancer grant INCa-DGOS-4654). The authors declare no competing financial interests, and the Fondation ARC pour la recherche contre le cancer (to E. Segura). M. Durand was supported by a PhD scholarship from Université Paris Descartes. P

E. Amigorena, ;. M. Segura, T. Durand, T. Pirnay, S. Naessens et al., Segura performed experiments. T. Walter designed the pipeline and software for analysis of imaging mass cytometry data

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