Growth of CD19⁺ cells after short-term (3 days) incubation in FL + IL-7 or FL + IL-7 + IL-10. Sorted CD19⁺ cells were cultured in FL + IL-7 in the presence or absence of IL-10 as indicated. After 3 days of incubation, the number of viable cells was establsihed and CD19 expression examined by flow cytometry. Data represent absolute cell numbers (mean ± SEM) of four separate experiments.