The IL-1 family is a central mediator of innate immunity and inflammation, consisting of 7 agonist ligands (IL-1α, IL-1β, IL-18, IL-33, IL-36α, β, γ), three receptor antagonists (IL-1Ra, IL-36Ra, IL-38), and an anti-inflammatory cytokine (IL-37). The IL-1R family includes 11 members, with key roles in signaling, decoy receptors, and negative regulators. Tight regulation via receptor antagonists, decoy receptors, and signaling inhibitors ensures a balance between innate immunity and inflammation. IL-1 family members are expressed in all innate immune cells and play a key role in the differentiation and function of innate and adaptive lymphoid cells. IL-1α and IL-1β are encoded by distinct genes, bind to the same receptor (IL-1R1), and have similar biological properties. However, they differ in their release mechanisms and downstream effects. IL-1α is released upon necrotic cell death and functions as an alarmin, while IL-1β is cleaved by caspase-1 to become active. IL-1β is involved in tumor angiogenesis and metastasis, and its production is regulated by the inflammasome. IL-1α is also involved in cancer progression and metabolism. IL-33 is a cytokine involved in type 2 immunity and inflammation, acting on innate and adaptive cells such as ILC2, Th2 cells, and M2 macrophages. It is released upon necrotic cell death and binds to the ST2 receptor, inducing Th2 responses and eosinophilia. IL-33 also plays a protective role in parasitic infections and is involved in various pathological conditions, including arthritis, sepsis, and fungal infections. IL-18 is a cytokine involved in Th1 and NK cell responses, and is processed by caspase-1. It is involved in autoimmune diseases, myocardial pathology, and sepsis. IL-18BP is a decoy receptor that inhibits IL-18 activity and limits Th1 responses. IL-36 family members, including IL-36α, β, γ, and IL-36Ra, bind to IL-1Rrp2 and are involved in Th1 and Th17 cell polarization. IL-36Ra acts as a receptor antagonist and is involved in psoriasis and fungal infections. IL-37 is an anti-inflammatory cytokine that inhibits IL-17 and IL-22 production and is involved in the regulation of adaptive immunity. IL-38 is a receptor antagonist of IL-36R and is involved in inflammatory diseases. Negative regulators of the IL-1 system include IL-1R2, IL-18BP, IL-The IL-1 family is a central mediator of innate immunity and inflammation, consisting of 7 agonist ligands (IL-1α, IL-1β, IL-18, IL-33, IL-36α, β, γ), three receptor antagonists (IL-1Ra, IL-36Ra, IL-38), and an anti-inflammatory cytokine (IL-37). The IL-1R family includes 11 members, with key roles in signaling, decoy receptors, and negative regulators. Tight regulation via receptor antagonists, decoy receptors, and signaling inhibitors ensures a balance between innate immunity and inflammation. IL-1 family members are expressed in all innate immune cells and play a key role in the differentiation and function of innate and adaptive lymphoid cells. IL-1α and IL-1β are encoded by distinct genes, bind to the same receptor (IL-1R1), and have similar biological properties. However, they differ in their release mechanisms and downstream effects. IL-1α is released upon necrotic cell death and functions as an alarmin, while IL-1β is cleaved by caspase-1 to become active. IL-1β is involved in tumor angiogenesis and metastasis, and its production is regulated by the inflammasome. IL-1α is also involved in cancer progression and metabolism. IL-33 is a cytokine involved in type 2 immunity and inflammation, acting on innate and adaptive cells such as ILC2, Th2 cells, and M2 macrophages. It is released upon necrotic cell death and binds to the ST2 receptor, inducing Th2 responses and eosinophilia. IL-33 also plays a protective role in parasitic infections and is involved in various pathological conditions, including arthritis, sepsis, and fungal infections. IL-18 is a cytokine involved in Th1 and NK cell responses, and is processed by caspase-1. It is involved in autoimmune diseases, myocardial pathology, and sepsis. IL-18BP is a decoy receptor that inhibits IL-18 activity and limits Th1 responses. IL-36 family members, including IL-36α, β, γ, and IL-36Ra, bind to IL-1Rrp2 and are involved in Th1 and Th17 cell polarization. IL-36Ra acts as a receptor antagonist and is involved in psoriasis and fungal infections. IL-37 is an anti-inflammatory cytokine that inhibits IL-17 and IL-22 production and is involved in the regulation of adaptive immunity. IL-38 is a receptor antagonist of IL-36R and is involved in inflammatory diseases. Negative regulators of the IL-1 system include IL-1R2, IL-18BP, IL-