Abstract 1272: Myeloid leukemia cell lines suppress T cell activation and proliferation.

In preliminary experiments to develop the K562 human leukemia cell line as an artificial antigen presenting cell we found that K562 cells strongly inhibited T cell proliferation. To explore this phenomenon further we tested CD4+CD25- T cells from healthy donor PBMC as targets of proliferation suppression. Targets were co-cultured with 3 chronic myeloid leukemia (CML) derived cell lines (K562, BV173 and CML1 established from a CML patient in our laboratory), two monocytic leukemia derived cell lines (THP-1 and U937), the myeloid leukemia derived cell line (KG1a) and the Burkitt lymphoma cell line (Daudi). To evaluate early activation, CD154 expression was tested by flow cytometry 16h after stimulation with CD3/CD28 beads. T cell proliferation was tested by CFSE dilution in T cells stimulated for 72h. All myeloid lines blocked CD154 expression (10.9-62.8% of control at 1:8 target: suppressor ratio). In CFSE proliferation assay, K562, KG1a, CML1, THP-1 and U937 induced comparable suppression (28.4-93.9%, at 1:8 ratio). In contrast, BV173 and Daudi cells were the least suppressive (4.96-23.0%, P Citation Format: Kazushi Tanimoto, Sawa Ito, Samantha Miner, Pawel Muranski, Nancy F. Hensel, J. Joseph Melenhorst, A. John Barrett. Myeloid leukemia cell lines suppress T cell activation and proliferation. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1272. doi:10.1158/1538-7445.AM2013-1272