Gustave Ronteix, Shreyansh Jain, Christelle Angely, Marine Cazaux, Roxana Khazen, Philippe Bousso, Charles N. Baroud, Microfluidique Physique et Bio-ingénierie - Physical Microfluidics and Bioengineering, Institut Pasteur [Paris] (IP)-École polytechnique (X)-Université Paris Cité (UPCité)-Institut Polytechnique de Paris (IP Paris), Laboratoire d'hydrodynamique (LadHyX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Dynamiques des Réponses immunes - Dynamics of Immune Responses, Institut Pasteur [Paris] (IP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris Cité (UPCité), P.B. is funded by Institut Pasteur, Inserm and an advanced grant from the European Research Council (ENLIGHTEN). G.R. is funded by the Direction Générale de l’Armement. The authors acknowledge the support of the Biomaterials and Microfluidics platform and the FabLab at Institut Pasteur., The authors acknowledge enlightening discussions with Clément Roussel, Andrey Aristov, Raphael Tomasi, Gabriel Amselem and all members of the Baroud team. Raphael Voituriez is gratefully acknowledged for his comments on the probabilistic descriptions., European Project: 741167,ERC-2016-ADG,ENLIGHTEN(2018), HUGOT, Bérengère, and INTEGRATION AND PROPAGATION OF IMMUNOLOGICAL SIGNALS DURING CANCER AND INFECTION - ENLIGHTEN - 2018-01-01 - 2022-12-31 - 741167 - VALID