C-C chemokine receptor type 4 is a protein that in humans is encoded by the CCR4 gene. [5] [6] [7] CCR4 has also recently been designated CD194 (cluster of differentiation 194).
The protein encoded by this gene belongs to the G protein-coupled receptor family. It is a receptor for the following CC chemokines:
Chemokines are a group of small structurally related proteins that regulate cell trafficking of various types of leukocytes. The chemokines also play fundamental roles in the development, homeostasis, and function of the immune system, and they have effects on cells of the central nervous system as well as on endothelial cells involved in angiogenesis or angiostasis. [7]
CCR4 is a cell-surface protein and should not be confused with the unrelated carbon catabolite repression-negative on TATA-less (CCR4-Not), a nuclear protein complex that regulates gene expression.
CCR4 is often expressed on leukemic cells in cutaneous T-cell lymphoma (CTCL). [10]
Mogamulizumab is a humanised monoclonal antibody targeted at CCR4 and is an investigational drug for CTCL. [10]
Chemokine ligand 3 (CCL3) also known as macrophage inflammatory protein 1-alpha (MIP-1-alpha) is a protein that in humans is encoded by the CCL3 gene.
Chemokine ligand 20 (CCL20) or liver activation regulated chemokine (LARC) or Macrophage Inflammatory Protein-3 (MIP3A) is a small cytokine belonging to the CC chemokine family. It is strongly chemotactic for lymphocytes and weakly attracts neutrophils. CCL20 is implicated in the formation and function of mucosal lymphoid tissues via chemoattraction of lymphocytes and dendritic cells towards the epithelial cells surrounding these tissues. CCL20 elicits its effects on its target cells by binding and activating the chemokine receptor CCR6.
Chemokine ligand 21 (CCL21) is a small cytokine belonging to the CC chemokine family. This chemokine is also known as 6Ckine, exodus-2, and secondary lymphoid-tissue chemokine (SLC). CCL21 elicits its effects by binding to a cell surface chemokine receptor known as CCR7. The main function of CCL21 is to guide CCR7 expressing leukocytes to the secondary lymphoid organs, such as lymph nodes and Peyer´s patches.
C-C motif chemokine 22 is a protein that in humans is encoded by the CCL22 gene.
CCL17 is a powerful chemokine produced in the thymus and by antigen-presenting cells like dendritic cells, macrophages, and monocytes. CCL17 plays a complex role in cancer. It attracts T-regulatory cells allowing for some cancers to evade an immune response. However, in other cancers, such as melanoma, an increase in CCL17 is linked to an improved outcome. CCL17 has also been linked to autoimmune and allergic diseases.
Fractalkine, also known as chemokine ligand 1, is a protein that in humans is encoded by the CX3CL1 gene.
Chemokine ligand 19 (CCL19) is a protein that in humans is encoded by the CCL19 gene.
The "C" sub-family of chemokine receptors contains only one member: XCR1, the receptor for XCL1 and XCL2.
CC chemokine receptors are integral membrane proteins that specifically bind and respond to cytokines of the CC chemokine family. They represent one subfamily of chemokine receptors, a large family of G protein-linked receptors that are known as seven transmembrane (7-TM) proteins since they span the cell membrane seven times. To date, ten true members of the CC chemokine receptor subfamily have been described. These are named CCR1 to CCR10 according to the IUIS/WHO Subcommittee on Chemokine Nomenclature.
Chemokine ligand (XCL1) is a small cytokine belonging to the C chemokine family that is also known as lymphotactin. Chemokines are known for their function in inflammatory and immunological responses. This family C chemokines differs in structure and function from most chemokines. There are only two chemokines in this family and what separated them from other chemokines is that they only have two cysteines; one N-terminal cysteine and one cysteine downstream. These both are called Lymphotactin, alpha and beta form, and claim special characteristics only found between the two. Lymphotactins can go through a reversible conformational change which changes its binding shifts.
Chemokine ligand 2 (XCL2) is a small cytokine belonging to the XC chemokine family that is highly related to another chemokine called XCL1. It is predominantly expressed in activated T cells, but can also be found at low levels in unstimulated cells. XCL2 induces chemotaxis of cells expressing the chemokine receptor XCR1. Its gene is located on chromosome 1 in humans.
C-C chemokine receptor type 1 is a protein that in humans is encoded by the CCR1 gene.
Chemokine receptor 6 also known as CCR6 is a CC chemokine receptor protein which in humans is encoded by the CCR6 gene. CCR6 has also recently been designated CD196. The gene is located on the long arm of Chromosome 6 (6q27) on the Watson (plus) strand. It is 139,737 bases long and encodes a protein of 374 amino acids.
C-C chemokine receptor type 10 is a protein that in humans is encoded by the CCR10 gene.
C-C chemokine receptor type 3 is a protein that in humans is encoded by the CCR3 gene.
Chemokine receptor 8, also known as CCR8, is a protein which in humans is encoded by the CCR8 gene. CCR8 has also recently been designated CDw198.
Chemokine-binding protein 2 is a protein that in humans is encoded by the CCBP2 gene.
C-C motif chemokine 4-like is a protein that in humans is encoded by the CCL4L1 gene.
Interferon-alpha/beta receptor alpha chain is a protein that in humans is encoded by the IFNAR1 gene.
C-C motif chemokine ligand 27 is a protein that in humans is encoded by the CCL27 gene.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.