IL18R1 - Interleukin 18 Receptor 1 | Elisa - Clia - Antibody - Protein

Background

Interleukin-18 Receptor 1 (IL18R1) is a type I transmembrane protein that plays a crucial role in the immune response. It is a part of the interleukin-1 receptor family and is primarily involved in the binding and signaling of interleukin-18 (IL-18), a cytokine that is pivotal in inflammatory and immune responses. IL18R1 is expressed on a variety of immune cells, including T cells, natural killer (NK) cells, macrophages, and dendritic cells. It is involved in Th1 cell differentiation, the production of interferon-gamma (IFN-γ), and the enhancement of cytotoxic activity in NK cells. The receptor's engagement with IL-18 is essential for initiating and regulating immune responses, particularly in the context of infection, inflammation, and autoimmune diseases.

Protein Structure

IL18R1 consists of several key structural components:

• Extracellular Domain: This domain includes three immunoglobulin (Ig)-like domains that are crucial for binding IL-18.
• Transmembrane Domain: This single-pass transmembrane helix anchors the receptor in the cell membrane.
• Intracellular Domain: The intracellular tail contains several conserved motifs that are involved in signal transduction, primarily through the recruitment and activation of intracellular signaling molecules such as MyD88 and IRAKs (IL-1 receptor-associated kinases).

Classification and Subtypes

IL18R1 belongs to the IL-1 receptor family and forms a complex with IL-18 receptor accessory protein (IL18RAP) to exert its biological effects. There are no distinct subtypes of IL18R1, but its activity is modulated through its interaction with IL18RAP.

Function and Biological Significance

IL18R1 plays a pivotal role in the immune system:

• Th1 Cell Differentiation: IL18R1, in conjunction with IL-18, promotes the differentiation of naive T cells into Th1 cells, which are essential for the cell-mediated immune response.
• Interferon-Gamma Production: Activation of IL18R1 by IL-18 significantly enhances the production of IFN-γ, a critical cytokine for antiviral and antibacterial immunity.
• Natural Killer Cell Activation: IL18R1 is vital for the activation and cytotoxic function of NK cells, enhancing their ability to destroy infected or malignant cells.
• Inflammatory Response: IL18R1 is involved in the regulation of inflammatory responses, contributing to the pathogenesis of various inflammatory and autoimmune diseases.

Clinical Issues

Dysregulation of IL18R1 signaling has been implicated in several diseases:

• Autoimmune Diseases: Overactivation of IL18R1 has been associated with autoimmune conditions such as rheumatoid arthritis, Crohn's disease, and psoriasis, where excessive inflammation is a hallmark.
• Infections: IL18R1 is critical in the immune response to infections; deficiencies or alterations in its signaling can result in impaired pathogen clearance and increased susceptibility to infections.
• Cancer: Abnormal IL18R1 signaling may contribute to the tumor microenvironment by modulating immune surveillance and the inflammatory milieu.

Summary

IL18R1 (Interleukin-18 Receptor 1) is a crucial component of the immune system, playing significant roles in Th1 cell differentiation, IFN-γ production, and NK cell activation. Structurally, it comprises extracellular Ig-like domains, a transmembrane domain, and an intracellular signaling domain. The receptor is vital for mediating responses to infections, regulating inflammation, and maintaining immune homeostasis. Dysregulation of IL18R1 signaling is implicated in autoimmune diseases, infections, and cancer, making it a potential target for therapeutic interventions aimed at modulating immune responses. Understanding IL18R1's function and regulation is essential for developing new treatments for these conditions.