CXCL5 (full name C-X-C motif chemokine 5) is a protein coding gene that is a part of the CXC subfamily of chemokines. It is also identified by the names ENA-78, SCYB5, and C-X-C motif chemokine ligand 5. It is expressed primarily on epithelial cells.
CXCL5 is associated to a number of diseases including pediatric ulcerative colitis and acute cervicitis. In humans, the gene’s encoding is over four exons within chromosone four, along with other members of the CXCL5 family and cytokines. Its external identifications include OMIM: 600324 and HomoloGene: 88672. Since being identified in the 1990s, research has discovered a lot of information about the gene, its role and relationships. It has been linked to various conditions as well as potential management ideas.
CXCL5 protein expression is found in the brain’s cerebral cortex, hippocampus and caudate. It is also expressed in skeletal muscle tissue and the pancreas. The RNA expressions is found in the brain, lungs, appendix, lymph nodes, gallbladder urinary bladder, breast, and prostate.
The CXCL5 gene is proposed to bind with the G-protein coupled receptor chemokine and interacts with the CXCR2 receptor. Scientific studies with mice deficient of CXCL5 found that the gene is crucial in the regulation of CXCR2 neutrophil trafficking during pulmonary defense. Alongside CXCL8, CXCL5 has been shown to have a significant influence in lung cancer angiogenesis, with elevated levels correlating to the vascularity of tumors. The expression of CXCL5 is also seen in eosinophils.
CXCL5 is key to controlling macrophage foam cell production in chronic inflammatory conditions like atherosclerosis, although it is not associated with neutrophil infiltration. The gene has also been used to increase scientific understandings of other inflammatory issues like arthritis and cystitis. ENA-78 is also prominent in the reduced sunburn pain, particularly during bouts of acute inflammatory. The protein is believed to be important for cancer cell proliferation, migration, and invasion.
The CXCL5 protein is produced due to the stimulation of cells with the inflammatory cytokines interleukin-1 or tumor necrosis factor-alpha and is purified by proprietary chromatographic techniques. The chemokine-mediated recruitment of NK cells can be a key defense mechanism against invasive aspergillosis while it has a role in sepsis development too.
CXCL5 induces chemotaxis, a rise in intracellular free calcium and exocytosis. Meanwhile, the protein gene has been shown to elevate in CSF during bacterial meningitis. This expression in linked to the recruitment of neutrophils to the central nervous system. This is also shown as an early response to various viral infections. The production of CXCL5 in inhibited when TNF-alpha antibodies are introduced to the body.
In recent times, CXCL5 has been pinpointed as a potential target for liver cancer as the gene was shown to be over-expressed in liver cancer cells. Secretion due to the inflammatory factors. In liver cancer, it may activate ERK ½. As such, the reduced regulation may hold a key to reduced proliferation and migration of cancerous cells. It can also influence the modulation of related proteins. Research into its role in this cancer, as well as others is ongoing.