IL-1α or IL-1β forms a complex with IL1R1 and IL1RAP at the cell membrane, mediating the acute phase of the proinflammatory process during infection or tissue damage, which initiates the IL-1 signaling pathway and leads to recruitment of adaptor proteins like myeloid differentiation primary response gene 88 (MYD88), Toll-interacting protein (TOLLIP), and IL-1 receptor-associated kinase 4 (IRAK4). Here, IL1R1 is linked to infection.