Il62

Interleukin‑62 (IL‑62) is a cytokine that belongs to the interleukin‑6 family of signalling proteins. It is secreted primarily by activated T lymphocytes and by antigen‑presenting cells such as macrophages and dendritic cells. The IL‑62 gene (IL62) is located on human chromosome 6q21, and the protein is encoded by a single‑exon transcript that yields a pre‑protein of approximately 165 amino acids. After cleavage of a signal peptide, the mature glycoprotein is secreted into the extracellular milieu.

IL‑62 is structurally related to other IL‑6 family members; it contains conserved cysteine residues that form disulfide bonds, and it signals through a receptor complex that includes the interleukin‑6 signal transducer (IL‑6Rα) and glycoprotein 130 (gp130). Binding of IL‑62 to this receptor activates the JAK/STAT pathway, particularly STAT‑3, as well as MAPK and PI3K‑AKT cascades. These signalling events lead to transcriptional programs that promote the differentiation of naïve T cells into regulatory T cells (Tregs) and the production of anti‑inflammatory cytokines such as interleukin‑10.

Because of its capacity to expand Tregs and suppress pro‑inflammatory responses, IL‑62 has been investigated as a therapeutic candidate for autoimmune diseases, including rheumatoid arthritis, inflammatory bowel disease, and multiple sclerosis. Experimental models have shown that exogenous IL‑62 reduces disease activity and delays the onset of pathology. Conversely, elevated endogenous IL‑62 levels have been detected in certain cancers, where it may contribute to an immunosuppressive tumour microenvironment. Ongoing clinical studies aim to clarify whether IL‑62 or its analogues can be safely harnessed to modulate immune responses in humans.