Phenotypic analysis of long-term surviving LTR-Tax CD4⁺ T cells. (A) Cell-surface phenotype analysis determined by flow cytometric analysis of CD4⁺ T-cell cultures propagated for 4 weeks as in Figure 3 from 3 LTR-Tax mice show a similar CD4⁺CD25⁺CD3- phenotype. (B) The indicated cytokines were assayed in supernatants from the same cultures of LTR-Tax CD4⁺ T cells collected at the indicated times between 2 and 20 weeks (concentration units: pg/mL, log-scale).