Chemokine C-C Receptor 4

Chemokine (Chemoattractant Cytokines) are small peptides that are potent activators and chemo-attractants for leukocyte subpopulations and other non-hemopoietic cells.  Chemokine receptors (CCR) belong to the superfamily of G protein-coupled receptors (GPCR), which regulate the trafficking and activation of leukocytes, and operate as co-receptors in the entry of HIV-1 and directing the proliferation and migration of immature neurons, glia and their precursors (1). Furthermore, chemokine receptors participate in the etiology and progression of various brain disorders, including AIDS dementia, neuro-inflammatory disease and neuroplasia, making them important potential therapeutic targets in these cases.  Induction of chemokines and infiltration of chemokine receptor-bearing cells has also been shown in a variety of animal models of renal diseases, as well as in human diseases and allograft rejection (2)

	Type	Cat #	Expression
1	CCR1	CCR-101AP	Melanoma, leukocytes, microglia, EC, podocytes
2	CCR2	CCR-201AP	Intestinal microvascular cells
3	CCR3	CCR-301AP	Microglia, podocytes
4	CCR4	CCR-401AP	Inflammatory cells
5	CCR5	CCR-501AP	Podocytes,

 

Activation of naïve T cells by specific antigen and cytokines, up-regulate cell adhesion molecules (CAM) as well as chemokine receptors on their surface, which directs them to migrate towards the inflamed tissues.  Several subtypes of CCR have been characterized (Table1). The CCR4 recrptors are activated by its ligand CCL17/TARC.  CCR4 has been implicated Not complex function parallel to or down stream of the bur1/2 that facilitate trimethylation of Histone H3 and regulate the transcription activity (3).  CCR4 is also involved in the chodrogenesis of mesenchymal stem cells, this process is  influenced by many molecules including CXCL1, FIT3L, CCR3 and CCR4.  The induction of CCR4 positive cell in duodenuim affects the food allergy, in skin-tropic condition, in allergic bronchopulmonary aspergillosis (ABPA) is a rare variant of severe asthma resulting from hypersensitivity to Aspergillus fumigatus.  The expression of CCR4 is decreases in several autoimmune diseases such as diabetes type1 and rheumatoid arthritis. 

The CCR4 receptor protein is approximately 45 kDa (360 amino acids) protein which has 7 transmembrane domains, characteristic of G-protein coupled receptors.  The CCR4 receptors are activated by Thymus and activation-regulated chemokine (TARC) that is expressed constitutively in thymus and transiently in stimulated peripheral blood mononuclear cells.  The protein has putative N-glycosylation sites near the extra cellular N-terminal end of the proteins.  The protein has a large 3^rd intra cellular loop which interacts with G-proteins.  The short carboxy terminal is intracellular and has putative post-translational sites.  The Anti-CCR4-selective antibodies were generated against conserved but unique sequences on various CCR4 receptors that are expressed only in CCR4 receptor subtype.  The polyclonal antibodies were affinity purified on an immobilized antigen based affinity chromatography.  These epitope-specific antibodies strongly label the CCR4 from the Western blot positive control CCR4 samples.  Anti-CCR-selective antibodies are also available in the form of fluorescent conjugates for direct application in IHC upon request at extra charge. FabGennix Int. Inc. also provides antibodies against several other GPCRs including orphan receptors.  FabGennix, Inc., will also provide Western blot positive controls for most of these antibodies in ready-to-use buffer for easy identification of  proteins.  Limited quantities of antigenic peptides are also available.  Please enquire for their availability before ordering.

For research use only, not for diagnostic or therapeutic use.