CD4⁺HLA-G1^acq+ T cells no longer respond to stimulation. (A) Proliferation analysis of purified CD4⁺ T cells taken prior to trogocytosis, CD4⁺HLA-G1^acq− T cells, and CD4⁺HLA-G1^acq+ T cells at the indicated times after purification. Uptake of HLA-G1 by T cells stopped their proliferation, which was partially maintained by masking HLA-G1 at the CD4⁺HLA-G1^acq+ T-cell surface. Results shown are representative of 3 independent experiments. (B) Proliferation analysis of purified CD4⁺ T cells taken prior to trogocytosis; CD4⁺HLA-G1^acq− and CD4⁺HLA-G1^acq+ T cells in medium supplemented with IL-2. Proliferation was measured at the indicated times after purification. Unlike masking HLA-G1 at the cell surface of CD4⁺HLA-G1^acq+ T cells, stimulation by exogenous IL-2 did not counteract HLA-G1–dependent proliferation inhibition. Results shown are representative of 3 independent experiments. (C) Analysis of allo-proliferative response of purified CD4⁺ T cells taken prior to trogocytosis, CD4⁺HLA-G1^acq− T cells, and CD4⁺HLA-G1^acq+ T cells using LCL-RSV as stimulator cells. HLA-G1 was masked when indicated. Results shown are representative of 3 independent experiments. (D) Analysis of allo-proliferative response of purified CD4⁺ T cells taken prior to trogocytosis; CD4⁺HLA-G1^acq− and CD4⁺HLA-G1^acq+ T cells using allogeneic PBMCs as stimulator cells. HLA-G1 was masked when indicated. Results shown are representative of 3 independent experiments.