Generation of TGFβ and PD-1 genomic fingerprints in primary CD4⁺ T cells from healthy donors. Principal components analysis (PCA) using the RNA fingerprints of TGFβ or PD-1 was performed to distinguish samples treated with TGFβ or PD-1 from the respective control samples. The first 3 principal components derived from (A) the TGFβ and (B) the PD-1 fingerprints are plotted. Plots depict samples stimulated with magnetic beads coated with CD3/CD28/MHC-I (●); samples treated with CD3/CD28/PD-1 (□); and samples treated with CD3/CD28/MHC-I in the presence of TGFβ (○).