Receptor for four distinct ligands: The TNF superfamily members TNFSF14/LIGHT and homotrimeric LTA/lymphotoxin-alpha and the immunoglobulin superfamily members BTLA and CD160, altogether defining a complex stimulatory and inhibitory signaling network (PubMed:9462508, PubMed:10754304, PubMed:18193050, PubMed:23761635). Signals via the TRAF2-TRAF3 E3 ligase pathway to promote immune cell survival and differentiation (PubMed:19915044, PubMed:9153189, PubMed:9162022). Participates in bidirectional cell-cell contact signaling between antigen presenting cells and lymphocytes. In response to ligation of TNFSF14/LIGHT, delivers costimulatory signals to T cells, promoting cell proliferation and effector functions (PubMed:10754304). Interacts with CD160 on NK cells, enhancing IFNG production and anti-tumor immune response (PubMed:23761635). In the context of bacterial infection, acts as a signaling receptor on epithelial cells for CD160 from intraepithelial lymphocytes, triggering the production of antimicrobial proteins and proinflammatory cytokines (By similarity). Upon binding to CD160 on activated CD4+ T cells, downregulates CD28 costimulatory signaling, restricting memory and alloantigen-specific immune response (PubMed:18193050). May interact in cis (on the same cell) or in trans (on other cells) with BTLA (PubMed:19915044) (By similarity). In cis interactions, appears to play an immune regulatory role inhibiting in trans interactions in naive T cells to maintain a resting state. In trans interactions, can predominate during adaptive immune response to provide survival signals to effector T cells (PubMed:19915044) (By similarity). {ECO:0000250|UniProtKB:Q80WM9, ECO:0000269|PubMed:10754304, ECO:0000269|PubMed:18193050, ECO:0000269|PubMed:19915044, ECO:0000269|PubMed:23761635, ECO:0000269|PubMed:9153189, ECO:0000269|PubMed:9162022, ECO:0000269|PubMed:9462508}.; (Microbial infection) Acts as a receptor for Herpes simplex virus 1/HHV-1. {ECO:0000269|PubMed:11511370, ECO:0000269|PubMed:9696799}.; (Microbial infection) Acts as a receptor for Herpes simplex virus 2/HHV-2. {ECO:0000269|PubMed:11511370, ECO:0000269|PubMed:9696799}.