Epcoritamab shifts T-cell differentiation toward Th1 polarization and enhances its differentiation into EM T cells. (A) Th1 and Th2 polarization of CD4⁺ T cells was assessed based on CCR6 and CXCR3 expression. Th1:Th2 ratio (log2 transformed) was calculated using the percentage of Th1 and Th2 subsets within CD4⁺ T cells in PBMCs from patients who were TN (n = 7), IBR (n = 10), ACA (n = 11), and RES (n = 7) after 7 days of culture with epcoritamab (blue symbols) or B12 control (red symbols). Each symbol represents 1 patient sample. (B) Th1 (interferon-gamma, tumor necrosis factor α, and granulocyte-macrophage colony-stimulating factor) and Th2 (interleukin-6 [IL-6] and IL-5) cytokine levels measured via Luminex cytokine assays in cell supernatants harvested after 7 days of exposure to epcoritamab (EPCO) or B12 control (B12) for samples from patients who were TN (n = 8), IBR (n = 8), and ACA (n = 8). (C) T-cell differentiation in CD4⁺ or CD8⁺ subsets was assessed via flow cytometry, separating naive T cells, CM T cells, EM T cells, and effector T cells, based on CCR7 and CD45RO expression for samples from patients who were TN (n = 7), IBR (n = 10), ACA (n = 11), and RES (n = 7) after 7 days of culture with EPCO or B12. Pie charts represent the median proportion of each subset. Asterisks indicate statistically significant expansion of CD4 and CD8 T-effector memory or T-central memory in cultures treated with EPCO compared with B12 as determined using Wilcoxon matched-pair signed rank test. ∗P< .05; ∗∗P< .01.