CD8 T cell responses during acute ECTV infection.

<p>Groups of female BALB/c mice were infected with 500 PFU ECTV-IFN-γbp^Δ, 500 PFU ECTV-WT or 2 x 10⁶ PFU ECTV-TK^Δ s.c., sacrificed on day 7 p.i. and splenic antigen-specific CD8 T cell responses were measured. (A) Percent specific lysis of ECTV-infected, ⁵¹Cr-labelled P815 targets by splenocytes from infected mice. ***, <i>P</i><0.001 in comparing % specific lysis of virus-infected target cells by splenocytes from ECTV-WT infected mice with splenocytes from ECTV-IFN-γbp^Δ- or ECTV-TK^Δ-infected mice at the indicated effector-to-target ratios. (B) Percent specific lysis of virus-infected (Total) or ECTV CD8 T cell determinant-pulsed, ⁵¹Cr-labelled P815 targets by splenocytes from ECTV-IFN-γbp^Δ-infected mice. **, <i>P</i><0.01 and ***, <i>P</i><0.001 in comparing % specific lysis of L^d-026 peptide-pulsed targets with D^d-043 or K^d-149.5 peptide-pulsed targets by splenocytes from ECTV-IFN-γbp^Δ-infected mice at the indicated effector-to-target ratios. (C) Percent ECTV peptide determinant-specific IFN-γ⁺ CD8 T cells in spleens of ECTV-IFN-γbp^Δ-infected mice. L^d-026-restricted responses were significantly higher (<i>P</i><0.01) compared with D^d-043- or K^d-149.5-restricted responses. (D) Numbers of ECTV-specific IFN-γ⁺ CD8 T cells in spleens of ECTV-IFN-γbp^Δ-infected mice. ***, <i>P</i><0.001 for comparisons between groups shown. (E) Numbers of peptide-MHC class I tetramer⁺ CD8 T cells in spleens of ECTV-IFN-γbp^Δ-infected mice. ***, <i>P</i><0.001 for comparisons between groups shown. (F) TCR Vβ chain expression by splenic CD8 T cells from virus-infected mice. <i>P</i> values for all panels were obtained by Mann-Whitney U test.