{"paper_id":"33cfc721-6438-4114-b0b3-568ab4194dfd","body_text":"Abstract\nGene regulatory networks encode the fundamental logic of cellular functions, but systematic network mapping remains challenging, especially in cell states relevant to human biology and disease. Here, we perturbed all expressed genes across 22 million primary human CD4+ T cells from four donors and developed a probe-based perturb-seq platform to measure the transcriptome effects in cells at rest and after stimulation. These data allow us to map genes that regulate known and novel pathways, including novel regulators of cytokine production. Importantly, active regulators and the gene programs they control change dramatically across stimulation conditions. Perturbation signatures enabled us to model T cell states observed in population-scale transcriptomic atlases, nominating regulators of Th1 and Th2 polarization and of age-related T cell phenotypes. Finally, we leveraged perturb-seq to implicate context-specific gene regulatory pathways in autoimmune disease risk. Our data provide a foundational resource to decode human immune function and genetic variation and for new approaches to study gene regulatory networks.\nCompeting Interest Statement\nA.M. is a cofounder of Site Tx, Arsenal Biosciences, and Survey Genomics, serves on the boards of directors at Site Tx, and Survey Genomics, is a member of the scientific advisory boards of network.bio, Site Tx, Arsenal Biosciences, Cellanome, Survey Genomics, NewLimit, Amgen, and Tenaya, owns stock in network.bio, Arsenal Biosciences, Site Tx, Cellanome, NewLimit, Survey Genomics, Tenaya and Lightcast and has received fees from network.bio, Site Tx, Arsenal Biosciences, Cellanome, Spotlight Therapeutics, NewLimit, Abbvie, Gilead, Pfizer, 23andMe, PACT Pharma, Juno Therapeutics, Tenaya, Lightcast, Trizell, Vertex, Merck, Amgen, Genentech, GLG, ClearView Healthcare, AlphaSights, Rupert Case Management, Bernstein and ALDA. A.M. is an investor in and informal advisor to Offline Ventures and a client of EPIQ. The Marson laboratory has received research support from Biohub/Chan Zuckerberg Initiative, the Parker Institute for Cancer Immunotherapy, the Emerson Collective, Arc Institute, Juno Therapeutics, Epinomics, Sanofi, GlaxoSmithKline, Gilead and Anthem and reagents from 10x, Ultima, Genscript, Illumina and Cellanome. The remaining authors declare no conflict of interest.","source_license":"CC-BY-4.0","license_restricted":false}