G-protein coupled receptor expressed in lymphocytes that acts as a chemotactic receptor for B-cells, T-cells, splenic dendritic cells, monocytes/macrophages and astrocytes (PubMed:19597478, PubMed:19615922, PubMed:21844396, PubMed:21796211, PubMed:21796212, PubMed:27147029). Receptor for oxysterol 7-alpha,25-dihydroxycholesterol (7-alpha,25-OHC) and other related oxysterols (PubMed:21796211, PubMed:21796212). Mediates cell positioning and movement of a number of cells by binding the 7-alpha,25-OHC ligand that forms a chemotactic gradient (PubMed:21796211, PubMed:21796212, PubMed:27147029). Binding of 7-alpha,25-OHC mediates the correct localization of B-cells during humoral immune responses (PubMed:21796211, PubMed:21796212). Collaborates with CXCR5 to mediate B-cell migration; probably by forming a heterodimer with CXCR5 that affects the interaction between of CXCL13 and CXCR5 (PubMed:21948984, PubMed:22913878). Guides B-cell movement along the B-cell zone-T-cell zone boundary and later to interfollicular and outer follicular regions (PubMed:19615922, PubMed:19597478, PubMed:21844396). Its specific expression during B-cell maturation helps position B-cells appropriately for mounting T-dependent antibody responses (PubMed:19615922). Also acts as a chemotactic receptor for some T-cells upon binding to 7-alpha,25-OHC ligand (PubMed:27147029). Promotes follicular helper T (Tfh) cells differentiation by positioning activated T-cells at the follicle-T-zone interface, promoting contact of newly activated CD4 T-cells with activated dendritic cells and exposing them to Tfh-cell-promoting inducible costimulator (ICOS) ligand (PubMed:27147029). Expression in splenic dendritic cells is required for their homeostasis, localization and ability to induce B- and T-cell responses: GPR183 acts as a chemotactic receptor in dendritic cells that mediates the accumulation of CD4(+) dendritic cells in bridging channels (PubMed:23682316, PubMed:23502855). Regulates migration of astrocytes and is involved in communication between astrocytes and macrophages (PubMed:25297897, PubMed:27166278). Promotes osteoclast precursor migration to bone surfaces (PubMed:26438360). Signals constitutively through G(i)-alpha, but not G(s)-alpha or G(q)-alpha (By similarity). Signals constitutively also via MAPK1/3 (ERK1/2) (By similarity). Homodimer and heterodimer. Heterodimerizes with CXCR5; leading to modulate the interaction between of CXCL13 and CXCR5. Expressed in mature B-cells and increases in expression early after activation, before being down-regulated in germinal center B-cells (PubMed:19597478). Expressed in astrocytes (PubMed:25297897). Specifically expressed in CD4(+) dendritic cells but not in CD8(+) dendritic cells (PubMed:23682316, PubMed:23502855). Expressed in monocyte/osteoclasts precursors and mature osteoclasts (PubMed:26438360). Up-regulated during B-cell maturation in the bone marrow, and is expressed in mature recirculating B-cells in bone marrow, spleen and lymph nodes (PubMed:19597478). Up-regulated in B-cells after BCR and CD40 engagement (PubMed:19597478). Down-regulated by lipopolysaccharide (LPS) in astrocytes (PubMed:27166278). Expression is directly down-regulated by BCL6 (PubMed:25176650). Mice display a reduction in the early antibody response to a T-dependent antigen (PubMed:19597478). B-cells fail to move to the outer follicle at day 2 of activation, and instead are found in the follicle center (PubMed:19615922). Mice have normal numbers of B- and T-cells and organized follicles and T-cell compartments are present (PubMed:19615922). Mice show a decreased number of splenic CD4(+) dendritic cells and defective priming of T- and B-cell response (PubMed:23682316, PubMed:23502855). Reduced follicular helper T (Tfh) cells (PubMed:27147029). T-cells fail to accumulate in the outer T zone at either time point and instead remain dispersed throughout the T zone (PubMed:27147029). GSK682753A (8-[(2E)-3-(4-chlorophenyl)prop-2-enoyl]-3-[(3,4-dichlorophenyl)methyl]-1-oxa-3,8-diazaspiro[4.5]decan-2-one), an inverse agonist, selectively inhibits the constitutive activity of GPR183 with high potency and efficacy. Belongs to the G-protein coupled receptor 1 family.