library_construction_protocol: The day of the assay, frozen tissues were thawed in 10ml of R10 before cutting and fresh biopsies were chopped upon reception. Some biopsies were processed fresh. Tissues were cut with scalpels in a Petri dish containing few microliters of R10 medium. Fragments were transferred in a 2ml Eppendorf tube with 1ml of digestion mix (RPMI + 2% Gelatin + 50 IU/mL Collagenase I + 50 IU/mL Collagenase IV + 30 IU/mL Deoxyribonuclease I + 0.1% RNasin and incubated 15-20 minutes at 37°C under agitation at 130 rpm. Digestion reaction was stopped by adding 500ul of R10 to the mix. Digested fragments were filtered on a 70um strainer placed on the top of a 50ml Falcon tube. 1ml of R10 was added to the filter before filtering the cell suspension. The remaining pieces were smashed against the filter using the plunger of a 2ml syringe and washed with 10-15ml of R10. Suspension was centrifuged 5min at 400g and supernatant discarded. For counting and estimation of viability with Trypan blue, cells were resuspended in an appropriate volume (300 to 500ul) of PBS + 1%Gelatin + 0.1%RNasin according to the pellet size. When cell number was sufficient, a maximum of 15'000 live cells per sample was loaded into the Chromium machine for encapsulation and barcoding using the Next GEM Single Cell 5' Library and Gel beads kit v1.1. Resulting cDNA was amplified with 15 PCR cycles then 5GEX libraries were constructed according to 10XGenomics protocol (CG000208). Quality controls were performed on a Fragment Analyzer (Agilent) and quantification of libraries was done with the Qubit HS dsDNA assay kit (InVitrogen).