The history of discovery of Interleukin-1: A fundamental cytokine of the innate immune response

The discovery of IL-1 marked the beginning of research on soluble mediators of immune responses and initiated studies on inflammatory responses to tissue damage. Initially termed “endogenous leukocyte pyrogen” (derived from the Greek word ‘pyr’ for fire), due to its role in inducing fever, research on this molecule led to the identification of numerous related soluble factors, collectively named the IL-1 family. Additionally, the study of IL-1 laid the groundwork for characterizing a variety of structurally and functionally related receptors, which are crucial in regulating immune responses. Significantly, the IL-1 family plays a key role in inflammation, response to microbes, and acts as an inducer of both autoimmune and autoinflammatory pathologies, and it is also associated with cancer. In this latter context, both pro-tumor and anti-tumor roles of IL1 family members have been highlighted. Therefore, the IL-1 family molecules present many aspects that are still under active study today. In fact, numerous researchers are engaged in this line of investigation, exploring potential treatments for various diseases.