CD Antigens
Product List
MSR1 Human
Macrophage Scavenger Receptor 1 Human Recombinant
MSR1 is fused to a 23 amino acid His-tag at N-terminus & purified by proprietary chromatographic techniques.
Introduction
CD204, also known as Macrophage Scavenger Receptor 1 (MSR1) or Scavenger Receptor-A (SR-A), is a member of the class A scavenger receptors. These receptors are integral membrane glycoproteins primarily expressed on macrophages and dendritic cells . CD204 is involved in the binding and internalization of a wide range of ligands, including modified low-density lipoproteins (LDLs), microbial pathogens, and apoptotic cells .
Key Biological Properties: CD204 is a trimeric protein that exists in three isoforms (types 1, 2, and 3) generated by alternative splicing . Types 1 and 2 are functional receptors capable of mediating endocytosis, while type 3 does not internalize modified LDLs .
Expression Patterns and Tissue Distribution: CD204 is predominantly expressed on the surface of various macrophage types and dendritic cells . It is found in tissues such as the liver, lungs, spleen, and lymph nodes . The expression of CD204 is also noted in certain pathological conditions, including atherosclerosis and cancer .
Primary Biological Functions: CD204 plays a crucial role in the innate immune response by mediating the uptake and degradation of modified LDLs, pathogens, and apoptotic cells . It is involved in cholesterol metabolism, host defense, and the clearance of cellular debris .
Role in Immune Responses and Pathogen Recognition: CD204 functions as a pattern recognition receptor (PRR) that recognizes pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) . It facilitates the phagocytosis of pathogens and the activation of immune responses .
Mechanisms with Other Molecules and Cells: CD204 interacts with various ligands, including oxidized LDLs, bacterial components, and apoptotic cells . It forms complexes with other receptors, such as Toll-like receptors (TLRs), to enhance pathogen recognition and immune signaling .
Binding Partners and Downstream Signaling Cascades: Upon ligand binding, CD204 triggers downstream signaling pathways that involve the activation of transcription factors like NF-κB . This leads to the production of pro-inflammatory cytokines and the modulation of immune responses .
Regulatory Mechanisms Controlling Expression and Activity: The expression of CD204 is regulated at both the transcriptional and post-translational levels . Transcription factors such as NF-κB and STAT3 play a role in the transcriptional regulation of CD204 . Post-translational modifications, including glycosylation and phosphorylation, influence the stability and activity of the receptor .
Biomedical Research: CD204 is used as a marker for macrophage activation and polarization in research studies . It is also employed in the study of atherosclerosis, cancer, and other inflammatory diseases .
Diagnostic Tools: Antibodies targeting CD204 are utilized in diagnostic assays, including immunohistochemistry and flow cytometry, to detect macrophage populations and their activation states .
Therapeutic Strategies: Targeting CD204 has therapeutic potential in cancer immunotherapy and the treatment of inflammatory diseases . Strategies to modulate CD204 expression or function are being explored to enhance immune responses and reduce pathological inflammation .
Role Throughout the Life Cycle: CD204 plays a role in various stages of life, from development to aging . During development, it is involved in tissue homeostasis and the clearance of apoptotic cells . In aging and disease, CD204 contributes to the regulation of immune responses and the progression of conditions such as atherosclerosis and cancer .
