Reducing the amount of antibody used did result in lower levels of IL-2 secretion; mean (± SEM) IL-2 secretion was 131 ± 20 and 37 ± 23 pg/mL for CLL cells treated with 20 or 2 ng/mL soluble Ms κ+ anti-IgM, respectively (compared to 875 ± 130 pg/mL for 20 μg/mL). Here, MTR is linked to B-cell chronic lymphocytic leukemia.