Figure 6. pBTLA treated mice show a lower Th1 immune response. A: On day 14 after HSV-1 infection, single-cell suspensions of cornea cells were prepared from mice from different groups. Cells were stained by anti-CD3e-FITC, anti-CD4-APC, PE anti-mouse IFN-γ- or PE Rat IgG1 Isotype control as described in Methods. Dot plots represent the frequencies of CD4⁺ IFN-γ⁺ T cells from pBTLA treated mice, pcDNA3.1 treated mice, and PBS control mice when gated on the lymphocytes. The percentage of CD4⁺ T cells expressing IFN-γ is shown in the upper right quadrants. B: The bar diagram demonstrates the total number of CD4⁺ IFN-γ⁺ T cells in the cornea in different groups (n=6 in each group). Decreased numbers of CD4⁺ INF-γ⁺ T cells are noted in the corneas of pBTLA treated mice (*p<0.01 compared with control groups). C: On day 14 after HSV-1 infection, single-cell suspensions of cervical draining lymph nodes were prepared from mice from different groups. Cells were stained by anti-CD3e-FITC, anti-CD4-APC, PE anti-mouse IFN-γ-, or PE Rat IgG1 Isotype control. Dot plots represent the frequencies of IFN-γ⁺ T cells from different group mice. The number of IFN-γ⁺ T cells and the percentage of IFN-γ⁺ T cells in all T cells are shown in the right quadrants. D: The bar diagram demonstrates the total number of IFN-γ⁺ T cells in the DLNs in different groups (n=6 in each group). Fewer numbers of IFN-γ⁺ T cells in the DLN of pBTLA treated mice (*p<0.01 compared with control groups). E: On day 14 after HSV-1 infection, spleen cells of the mice from different groups (n=6 in each group) were used in antigen specific ELISA. Levels of IFN-γ in pBTLA treated mice were lower than in pcDNA3.1 or PBS treated mice (*p<0.01).