Groups of mice were injected i.p. with 40 μg LTB-p24 conjugate; 40 μg LTB+40 μg gag p24; 40 μg gag p24 protein alone, or PBS. 13 days after initial immunization, splenic cells (as a source of APCs, 65%) were isolated from these mice, pooled and incubated with gag p24 for 5 hrs. Mesenteric lymph nodes (as a source of T cells, 90%) were pre-labeled with CFSE and added. Cultures were incubated for 4 days. On day 4, cells were harvested, washed, and acquired by flow cytometry. Data were analyzed by FlowJo software. Data shown represent pattern of cell division and numbers of divided cells (A and B). In B, the same data as in A is plotted to show more clearly the increase in cell division rate by the conjugate. 1, 2, 3, 4, 5, 6 represent generation numbers.
