Table I.

Phenotypic composition of αβ T cells stimulated with either T. gondii or PHAa

T. gondii-SeronegativeT. gondii-Seropositive
CD4+ (%)CD8+ (%)CD4+ (%)CD8+ (%)
Unstimulated52.048.371.528.5
StimulatedTachyzoites87.112.471.728.3
(blasts: 94.2)b(blasts: 6.0)(blasts: 66.4)(blasts: 33.6)
TLA89.310.186.213.8
(blasts: 96.0)(blasts: 3.7)(blasts: 93.5)(blasts: 6.5)
PHA49.150.446.653.7
  • a Values are derived by two-color flow cytometry using mAb specific for αβ TCR, CD4, and CD8 molecules. Cytofluorometric analysis was performed before or after a 7-day stimulation with PBMC that had been either infected with T. gondii tachyzoites or incubated with TLA or PHA. Results are representative of three independent experiments.

  • b T cell blasts were gated according to forward scatter. In the case of PHA, all T cells had blast characteristics as determined by cytofluorometric analysis.