FIGURE 1.
Stimulation with a variant viral epitope induces enhanced apoptosis in CD8+ CL-4 T cells. CL-4 T cells were stimulated in vitro with A/PR/8/34 or A/Japan/305/57 influenza virus-infected splenocytes (A) or with 10−5 M (B) or 10−6 M (C, D) PR/8 HA533–541 or Japan HA529–537 peptide-pulsed splenocytes. A and B, Viable cell counts were calculated using trypan blue exclusion at the indicated times poststimulation. Error bars represent SD. C, Detection of apoptotic cells by annexin V labeling of CL-4 T cells stimulated with Japan HA529–533 peptide. Histograms indicate annexin V staining on cells within the indicated gate at day 3 poststimulation. D, Forward and side scatter properties of CL-4 T cells poststimulation. Plots represent CD8+/CFSE+ cells. Numbers indicate percentage of cells within the dead gate.