Figure 4.

Comparison of precursor frequencies of CD4⁺ T cells taken from individual WT and μMT mice after treatment with chloroquine or after adoptive transfer of immune B cells. CD4⁺ T cells were taken at 50 days of infection from WT and μMT mice (a and c, respectively), WT and μMT mice treated with Chloroquine at 30 days of infection (b and d, respectively), and μMT mice that received 2 × 10⁷ immune B cells i.v. at 30 days of infection (e). The percentages of B220⁺ cells in the spleens of the reconstituted mice were: (1) 6.75%; (2) 6.95%; (3) 6.36%, and (4) 1%. Precursor frequencies of IFN-γ (▪) and T helper cells for Ab production (□) are shown for each mouse.