FIG. 2.

Immunization with rVV-ES-gB498-505 induces primary and memory CTL responses. C57BL/6 mice were immunized i.n. with 10⁷ PFU of rVV-ES gB498-505. Eight days later, the hilar (A) and submaxillary (B) lymph nodes were removed, and single-cell suspensions were formed. The effector lymph node cells were then tested for lytic activity at the indicated effector-to-target ratios against B6/WT-3 cells pulsed with 1 μM gB498-505 synthetic peptide and mock peptide-pulsed B6/WT-3 cells. For analysis of the CTLm response (C), we immunized i.n. five mice with rVV-ES-gB498-505 and three with rVV-ES-IV. Six weeks later, mice were sacrificed and their splenocytes were incubated for 7 days under LDA conditions as described in Materials and Methods. The graded splenocyte cultures were then tested for lytic activity against ⁵¹Cr-labeled B6/K-1,4,5 cells which were either pulsed with gB498-505 synthetic peptide or mock pulsed. Total CTLm per spleen was calculated as (CTLm frequency) × (viable cell yield per spleen).