Interestingly, using an ex vivo flow cytometry based assay of tumor cells cocultured with splenocytes, we observed that the siRNA nanoplexes were preferentially taken up by the tumor cells, compared to macrophages or T-cells (Supplementary Fig. 3G)39, suggesting that this nanoparticle approach might limit the effect of MK2 inhibition in immune cells. The gene discussed is MAPKAPK2; the disease is neoplasm.