IL5

IL5 also known as EDF or TRF, is a 115-amino acid-long (in human) TH2 cytokine and it belongs to the hematopoietic family. Different from other members of this cytokine family (interleukin 3 and GM-CSF), IL5 in its active form is a homodimer. The IL5 gene is located on chromosome 5 in humans, and chromosome 11 in the mouse, which is close to the genes encoding IL-3, IL-4, and GM-CSF, and they usually are co-expressed in TH2 cells. Initially, IL-5 was found as a T-cell-derived cytokine which triggers activated B cells for terminal differentiation into antibody-secreting plasma cells, at least in mice. At present, IL-5 was regarded as the main maturation and differentiation factor for eosinophils in mice and humans. Over-expression of IL-5 notably improves eosinophil numbers and antibody levels in vivo.
IL5 is also expressed on eosinophils and has been identified on the mast cells of asthmatic airways by immunohistochemistry. The expression of IL5 is modulated via a variety of transcription factors including GATA3. Importantly, IL5 has long been related to the cause of several allergic diseases, such as asthma and allergic rhinitis, wherein a large improvement in the number of circulating, airway tissue, and induced sputum eosinophils have been observed.
Gene ID: 3567
UniProt ID: P05113