Proliferation and survival of SS cultures in response to IL-16.
A) Dose titration assays at 1, 10 or 100 nM IL-16 show that most stages of malignant T-cells proliferate in response to 10nM IL-16. Cells were cultured for 3 days in the presence of cytokines before addition of 1μCi [3H]TdR. Cultures were harvested 16 hours post-pulse, and cpm from 5 replicates were expressed as stimulation index of media control (baseline). (normal = 1 donor, stage 1A = 2 patients, stage 1B = 6 patients, stage IV = 3 patients).
B) CTCL mitogenic cytokine cocktails were tested in different types of T cell lymphomas. IL-2, IL-15 and IL-7 (10 ng/ml) were used separately or in combination with IL-16 (10nM). SS cultures responded best to the combinations of IL-15/IL-2, or IL-15/IL-16, as demonstrated by this stage IB patient.
C) CTCL mitogenic cytokine cocktails were tested for their ability to support SS long-term cultures. Cells from various stages all responded best to a combination of IL-15 and IL-16, as demonstrated by these three representative patients.
D) SS stages above IA were maintained with 10nM IL-16 in culture for 2 weeks. Cells were cultured in triplicate and counted on day 14 by Trypan blue exclusion; data are expressed as fold above media control wells. (n=1 representative patient per stage, except n=2 for stage IB).