Adaptor molecules mediate negative regulation of macrophage inflammatory pathways: a closer look

Front Immunol. 2024 Feb 28:15:1355012. doi: 10.3389/fimmu.2024.1355012. eCollection 2024.

Abstract

Macrophages play a central role in initiating, maintaining, and terminating inflammation. For that, macrophages respond to various external stimuli in changing environments through signaling pathways that are tightly regulated and interconnected. This process involves, among others, autoregulatory loops that activate and deactivate macrophages through various cytokines, stimulants, and other chemical mediators. Adaptor proteins play an indispensable role in facilitating various inflammatory signals. These proteins are dynamic and flexible modulators of immune cell signaling and act as molecular bridges between cell surface receptors and intracellular effector molecules. They are involved in regulating physiological inflammation and also contribute significantly to the development of chronic inflammatory processes. This is at least partly due to their involvement in the activation and deactivation of macrophages, leading to changes in the macrophages' activation/phenotype. This review provides a comprehensive overview of the 20 adaptor molecules and proteins that act as negative regulators of inflammation in macrophages and effectively suppress inflammatory signaling pathways. We emphasize the functional role of adaptors in signal transduction in macrophages and their influence on the phenotypic transition of macrophages from pro-inflammatory M1-like states to anti-inflammatory M2-like phenotypes. This endeavor mainly aims at highlighting and orchestrating the intricate dynamics of adaptor molecules by elucidating the associated key roles along with respective domains and opening avenues for therapeutic and investigative purposes in clinical practice.

Keywords: adaptor proteins; alternative activation; inflammation; macrophage; signaling mechanism.

Publication types

  • Review
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Cytokines* / metabolism
  • Humans
  • Inflammation
  • Macrophages*
  • Signal Transduction

Substances

  • Cytokines
  • Adaptor Proteins, Signal Transducing

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by Cumulative Professional Development Allowance (CPDA) and Research Development Fund (RDF) from Indian Institute of Technology Indore (IITI) to MB. This work was also supported by the Max Planck Society, Institute for lung health (ILH), Cardio-Pulmonary Institute (CPI), German Center for Lung Research (DZL), DFG, SFB 1213 (Project A10), Frankfurt Cancer Institute (LOEWE FCI)) and the State of Hesse (LOEWE iCANx, Project A5, Area C).