Figure 1. PD-1⁺ T population is expanded and functionally active in FL.

(A) PD-1 expression on CD4⁺ or CD8⁺ T cells from biopsy specimens of a FL patient (FL) and tonsil (Ton). Box is to indicate a PD-1⁺ T population exists in both the CD4⁺ and CD8⁺ subsets. (B) Graphs showing percentages of PD-1⁺ CD4⁺ or CD8⁺ T cells from tonsil and FL. (C) TIM-3 expression by PD-1⁺ CD4⁺ or CD8⁺ T cells. (D) IFN-γ and granzyme B (GzmB) on PD-1⁺CD4⁺ or CD8⁺ T cells from lymph nodes of FL patients. Isotype control staining was performed to determine PD-1⁺ T cells. (E) Graph summarizes percentages of IL-2, IFN-γ, perforin (PFN) and GzmB by PD-1⁺ and PD-1^- in CD4⁺ and CD8⁺ T cells.