FPR - Formyl Peptide Receptor | Elisa - Clia - Antibody - Protein

Background:

Formyl Peptide Receptors (FPRs) are a group of G protein-coupled receptors (GPCRs) that play critical roles in the immune response, particularly in the recognition of microbial invaders and the regulation of inflammatory processes.Formyl Peptide Receptors were initially discovered in the 1970s through studies on neutrophils, where they were found to mediate chemotaxis towards bacterial peptides.FPRs are highly conserved across species, indicating their fundamental importance in host defense mechanisms.They play crucial roles in immune responses and inflammation, making them attractive targets for therapeutic intervention in various diseases, including infectious diseases, inflammatory disorders, and cancer. Further research into the signaling mechanisms and physiological functions of FPRs is needed to fully exploit their therapeutic potential.FPRs are activated by formylated peptides derived from bacterial proteins, particularly those released during bacterial infection or tissue damage. FPRs can also be activated by endogenous ligands, including host-derived peptides, such as annexin A1-derived peptides, and other molecules released during inflammation and tissue injury.

Structural Features:

• Transmembrane Protein: FPRs are seven-transmembrane domain receptors, typical of GPCRs.
• Topology: They consist of an extracellular N-terminus, seven transmembrane helices connected by intracellular and extracellular loops, and an intracellular C-terminus.
• Binding Site: The ligand-binding pocket for formyl peptides is located within the transmembrane domain.

Location:

• FPRs are primarily expressed on leukocytes, including neutrophils, monocytes, macrophages, and dendritic cells.
• They are also found on other cell types, including epithelial cells, endothelial cells, and certain neuronal cells.

Subtypes and Classification:

In humans, there are three main subtypes of FPRs: FPR1, FPR2/ALX, and FPR3.

• FPR1 and FPR2/ALX are the most extensively studied subtypes, while FPR3 has been less characterized.
• FPR1 and FPR2/ALX share significant sequence homology but exhibit distinct ligand specificities and signaling pathways.

Physiological Functions:

• Chemotaxis: FPR activation triggers the directional migration of leukocytes towards sites of infection or tissue damage.
• Phagocytosis: FPR signaling enhances phagocytic activity, allowing leukocytes to engulf and destroy microbial pathogens.
• Inflammatory Response: FPRs regulate the production and release of inflammatory mediators, such as cytokines, chemokines, and reactive oxygen species.
• Resolution of Inflammation: FPR2/ALX activation promotes the resolution of inflammation by stimulating the production of anti-inflammatory mediators and inhibiting pro-inflammatory signaling pathways.

Clinical Implications:

• Infectious Diseases: Dysregulation of FPR signaling has been implicated in the pathogenesis of infectious diseases, including bacterial infections and sepsis.
• Inflammatory Disorders: Aberrant FPR activation contributes to the development and progression of inflammatory disorders, such as rheumatoid arthritis, inflammatory bowel disease, and asthma.
• Cancer: FPRs may play dual roles in cancer progression, promoting tumor growth and metastasis through the modulation of inflammatory responses and immune evasion mechanisms.