AbstractMany players regulating the CD4+ T cell-mediated inflammatory response have already been identified. However, the critical nodes that constitute the regulatory and signalling networks underlying CD4 T cell responses are still missing. Using a correlation network-guided strategy based on time-series transcriptome data of human CD4+CD25- effector T cells (Teffs), here we identified VIMP (VCP-interacting membrane protein), one of the 25 genes encoding selenocysteine in humans, as a gene regulating the effector functions of human CD4 T cells. Knocking-down VIMP in Teffs enhanced their proliferation and expression of several cytokines, including IL-2 and CSF2. We identified VIMP as an endogenous inhibitor of cytokine production in Teffs via both, the E2F5 transcription regulatory pathway and the Ca2+/NFATC2 signalling pathway. Our work not only indicates that VIMP might be a promising therapeutic target for various diseases involving CD4 T cells, but also shows that our network-guided approach might be generally applicable to different types of cells and can significantly aid in predicting new functions of the genes of interest.One-sentence summaryUsing a network-guided approach, we identified that Selenoprotein S (SELS or VIMP) negatively regulates cytokine expression of human CD4+ effector T cells via the E2F5 and calcium Ca2+/NFATC2 pathways.