Abnormal Expression of BTLA and CTLA-4 Immune Checkpoint Molecules in Chronic Lymphocytic Leukemia Patients

Figure 5

Surface and cytoplasmic CTLA-4 expression in unstimulated and stimulated BTLA+ T cells from CLL patients and controls. The expression of CTLA-4 and BTLA in lymphocytes from patients and healthy controls was determined by flow cytometry. (a) and (c) show the cell surface stained for both immune checkpoints, while (b) and (d) show the cell surface labeled with anti-BTLA mAb and then intracellularly labeled with anti-CTLA-4 mAb. (a) The frequency of BTLA+sCTLA-4+ cells within PB and in vitro stimulated CD3+ lymphocytes in CLL patients and controls is shown. (b) The frequency of BTLA+cCTLA-4+ cells within PB and in vitro stimulated CD3+ lymphocytes in CLL patients and controls is shown. (c) The mean fluorescence intensity (MFI) of CTLA-4 molecules on the surface (sCTLA-4) of PB and in vitro stimulated CD3+ cells in CLL patients and controls is shown. (d) The mean fluorescence intensity (MFI) of CTLA-4 molecules in the cytoplasm (cCTLA-4) of PB and in vitro stimulated CD3+ cells in CLL patients and controls is shown. The horizontal lines and the boxes show the median values and interquartile ranges, respectively.