Human Interleukin 1 Alpha (IL1A) Protein

Background

IL1A is a pro-inflammatory cytokine and a member of the interleukin-1 (IL-1) family, acting as a potent mediator of inflammation, immune responses, and tissue homeostasis. IL1A is produced as a precursor protein that can function in its membrane-bound or cleaved active form following cellular stress, necrosis, or damage. It signals through the interleukin-1 receptor (IL1R1) and its co-receptor IL1RAP, activating downstream NF-κB, AP-1, and MAPK pathways, which drive the expression of pro-inflammatory cytokines, chemokines, and adhesion molecules. IL1A is primarily expressed by epithelial cells, keratinocytes, monocytes, and macrophages in response to infections, tissue injury, or inflammatory stimuli. It plays critical roles in host defense, fever induction, and leukocyte recruitment while also modulating tissue repair and homeostasis. Dysregulated IL1A activity contributes to chronic inflammatory diseases, cancer progression, and fibrosis. Knockout studies reveal impaired inflammatory responses, reduced leukocyte recruitment, and delayed tissue repair, highlighting IL1A's role in initiating inflammation, immune signaling, and maintaining tissue integrity.