Scavenger receptor class F member 1 (SREC-I) (SCARF1)

Scavenger receptor class F member 1 (SREC-I), also known as SCARF1, is a type I transmembrane protein that functions as a scavenger receptor on endothelial cells and antigen-presenting cells (APCs) such as dendritic cells and macrophages (UniProt Q9UHF0). It plays a pivotal role in the immune system by mediating the uptake of a wide range of ligands, including acetylated low-density lipoproteins, heat shock proteins (HSPs), and apoptotic cells (PubMed: 17641034). On APCs, SREC-I is particularly important for its ability to bind HSP-antigen complexes, facilitating their internalization and subsequent cross-presentation to CD8+ T cells, which is a critical step in generating anti-tumor immune responses (PubMed: 25108027). Furthermore, SREC-I is essential for efferocytosis, the process of clearing apoptotic debris; a deficiency in this receptor is linked to the development of systemic lupus erythematosus (SLE) due to the accumulation of autoantigens (PubMed: 21606508). In therapeutic development, SREC-I is targeted by investigational cancer vaccines, such as those using HSP70-peptide complexes, to enhance the delivery of tumor antigens to the immune system. It also serves as a potential entry point for various pathogens, including certain viruses and fungi, making it a target for research into anti-infective strategies.

Other names

SREC-ISREC1Scavenger receptor expressed on endothelial cells 1Acetyl-LDL receptor

SREC-I facilitates the binding and internalization of heat shock protein (HSP)-antigen complexes via receptor-mediated endocytosis, leading to the trafficking of antigens into the cross-presentation pathway for activation of CD8+ T cells.