Pomalidomide inhibits lipopolysaccharide (LPS) stimulated TNF-alpha release in human PBMC and in human whole blood with IC50 values of 13 nM and 25 nM, respectively. [1] Pomalidomide inhibits the growth of T regulatory cells which is stimulated by IL-2 with an IC50 of ~1 μM. [2] Treatment with Pomalidomide (6.4 nM-10 μM) increases the production of IL-2 in human peripheral blood T cells, and is slightly more potent in the CD4+ subset than in the CD8+ subset. Pomalidomide is significantly more potent than CC-5013 at elevating IL-2, IL-5, and IL-10 levels, but only slightly more potent than CC-5013 at elevating IFN-γ levels. Pomalidomide enhances SEE and Raji cells induced AP-1 transcriptional activity in Jurkat cells in a dose-dependent manner, with a maximal enhancement of 4-fold at 1 μM. [3] Exposure of Raji cells to various concentrations of Pomalidomide (2.5-40 μg/mL) for 48 hours leads to a significant decrease in cell proliferation and DNA synthesis. There is a reduction of ~40% compared to vehicle-treated controls