Acts as a negative regulator of innate and adaptive immunity by maintaining immune homeostasis (PubMed:27043859). Plays a regulatory role in the Toll-like signaling pathway by determining the strength of LPS-induced signaling and gene expression (PubMed:32188758). Inhibits TCR-mediated T-cell activation and negatively regulate T-cell function to prevent hyperresponsiveness (By similarity). Also inhibits autolysosome formation via negatively modulating MTOR activation by interacting with RAC1 and promoting the disassociation of the RAC1-MTOR complex (PubMed:32460619). Plays an essential role in NK-cell biology by acting as a checkpoint and displaying an expression pattern correlating with NK-cell maturation process and by negatively regulating NK-cell maturation and antitumor immunity (By similarity). Mechanistically, suppresses IL-15-triggered mTOR activity in NK-cells (By similarity). {ECO:0000250|UniProtKB:Q9D8Y7, ECO:0000269|PubMed:27043859, ECO:0000269|PubMed:32188758, ECO:0000269|PubMed:32460619}. This is the function of TIPE2 (TNF alpha induced protein 8 like 2, Ensembl gene identifier ENSG00000163154).