Interleukin-34 (IL-34)

Interleukin‑34 (IL‑34) is a secreted cytokine composed of 241 amino acids that forms homodimers. It belongs to the interleukin family and functions primarily by binding to the colony-stimulating factor 1 receptor (CSF‑1R), as well as other receptors such as PTP-zeta and syndecan‑1. Through these interactions, it promotes the growth, survival, differentiation, and function of monocytes and macrophages. IL‑34 plays key roles in tissue-specific development of myeloid cells—such as Langerhans cells in skin and microglia in brain—and regulates immune responses by influencing chemokine expression. Its expression is most abundant in spleen but also found across various tissues including thymus, liver, intestine, lung, heart, brain, kidney, testes and ovary. Alterations in its levels are implicated in disease pathogenesis including cancer progression (notably triple-negative breast cancer) and chronic inflammation[1][3][2][7].

Other names

IL-34IL34 proteinInterleukin 34IL-34 cytokine

Binds to colony-stimulating factor 1 receptor (CSF‑1R), activating signaling pathways that regulate proliferation, differentiation, survival of myeloid cells[3][1]