FIG. 1.

T cells were infected with PBj6.6 virus in the presence or absence of the indicated accessory cells. To prevent their proliferation, accessory cells were X- irradiated with 10,000 rads prior to plating. A total of 2.5 × 10⁴ Raji cells or 5 × 10⁴ autologous macrophages (cultured for 1 week prior to the experiment) were plated per well. The incorporation of [³H]thymidine by accessory cells alone was at background levels (not shown). Results shown are the mean values of three independent observations and are representative of three separate experiments yielding similar conclusions; error bars indicate the standard errors of mean values.