IL5 Gene

The IL5 gene encodes a cytokine (IL-5), a protein that acts as a growth and differentiation factor for both B cells and eosinophil granulocytes. The cytokine encoded plays an important role in regulating eosinophil formation, maturation, recruitment, and survival. Increased production of this cytokine may be associated with the pathogenesis of eosinophil-dependent inflammatory diseases.

The IL5 gene is located on chromosome 5 (5q31.1) within a cytokine gene cluster that also includes interleukin-4 (IL4), interleukin-13 (IL13), and CSF2. The IL5 gene and the genes encoding IL-4 and IL-13 may be coordinately regulated by long-range regulatory elements distributed over 120 kilobases on chromosome 5q31.

The encoded cytokine interleukin-5 binds to a heterodimeric receptor. A common beta subunit of the IL5 receptor and the receptors for interleukin 3 (IL3) and colony-stimulating factor 2 (CSF2/GM-CSF) exists. This also explains the cooperative efficiency of these cytokines.

Diseases associated with IL5 include IgE-mediated allergic diseases (Bogaczewicz J et al. 2016). Related signaling pathways include TGF-beta pathway and RET signaling. Gene Ontology (GO) annotations associated with this gene include cytokine activity and interleukin-5 receptor binding.

1. Bogaczewicz J et al.(2016) Medium-dose ultraviolet A1 phototherapy and mRNA expression of TSLP, TARC, IL-5, and IL-13 in acute skin lesions in atopic dermatitis.Int J Dermatol 55:856-863.
2. Castro M et al (2016) Treatment for severe eosinophilic asthma-consistent effect of anti-interleukin-5 antibodies? Lancet 388:2059-2060.
3. Hilvering B et al.(2015) Evidence for the efficacy and safety ofanti-interleukin-5 treatment in the management of refractory eosinophilic asthma. Ther Adv Respir Dis 9:135-145.
4. McLeod O et al. (2016) Genetic loci on chromosome 5 are associated with circulating levels of interleukin-5 and eosinophil count in a European population with high risk for cardiovascular disease. Cytokine 81:1-9.
5. Simon D et al (2007) Anti-interleukin-5 therapy for eosinophilic diseases. Dermatologist 58: 122-127
6. Teng Y et al. (2014) Tobacco smoking associated with the increases of the bronchoalveolar levels of interleukin-5 and interleukin-1 receptor antagonist in acute eosinophilic pneumonia. Eur Rev Med Pharmacol Sci 18:887-893.
7. Varricchi G et al. (2016) Interleukin-5 pathway inhibition in the treatment of eosinophilic respiratory disorders: evidence and unmet needs. Curr Opin Allergy Clin Immunol 16:186-200.