library_construction_protocol: Fresh samples were cut with a scalpel into 1mm3 fragments, viably frozen, and stored at -80°C in Cryostor® CS10. Samples involved by reactive processes, FL, or CLL were selected for downstream analyses. LN samples were thawed and digested with proteases at 37o C for up to 1 hr. Debris/cell clumps were removed by filtration through mesh with 100 μm pores and red cells were lysed. After staining with DAPI to exclude dead cells, CD45+ and CD45- cells were isolated by cell sorting and subjected immediately to scRNA-seq. Encapsulation and cDNA library generation (10X Genomics Single Cell 3′Kit V3.1) from sorted cells were per the manufacturer's protocol. cDNA libraries were sequenced to an average of 41,764 reads per cell using an Illumina Nextseq 500.