SRCR proteins uncovered: Their crucial role in inflammation

Abstract

The scavenger receptor cysteine-rich (SRCR) superfamily comprises a highly conserved group of extracellular soluble and membrane-attached glycoproteins that function as pattern recognition receptors against a diverse range of pathogenic determinants. While considerable attention has been devoted to their roles in microbial recognition, this perspective aims to emphasize the significant, yet previously overlooked, anti-inflammatory properties of circulating SRCR proteins, which may be even more crucial for immune regulation. In addition, we examine SRCR cell surface proteins that, despite exhibiting limited microbial recognition, have demonstrated potential in mitigating inflammation through their soluble forms released during infectious and inflammatory conditions. Collectively, the paper emphasizes the dual roles of these proteins in infection control and the regulation of inflammatory responses, spotlighting their therapeutic potential in managing inflammatory diseases and enhancing host defense mechanisms.

Keywords

Scavenger receptors / Pattern recognition receptors / Inflammation / Microbial recognition / Immune homeostasis

Funding

This work was supported by National Funds through Fundação para a Ciência e a Tecnologia (FCT), I.P., under the projects 2022.04792.PTDC and European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Individual Research Grant to L.O.

Conflict of interest

The authors declare they have no conflict of interest.

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