Human TLR4 Alexa Fluor® 700-conjugated Antibody

Applications

Please Note: Optimal dilutions should be determined by each laboratory for each application. General Protocols are available in the Technical Information section on our website.

Preparation and Storage

Background: TLR4

TLR4 is a 100 kDa type I transmembrane glycoprotein that belongs to the mammalian Toll-Like Receptor family of pathogen pattern recognition molecules. MD-2, also known as ESOP-1, is a 25 kDa secreted protein that is required for TLR4-mediated responses to bacterial lipopolysaccharide (LPS) (1-3). The human TLR4 cDNA encodes an 839 amino acid (aa) precursor that contains a 23 aa signal sequence, a 608 aa extracellular domain (ECD), a 21 aa transmembrane segment, and a 187 aa cytoplasmic domain. TLR4 contains 21 leucine rich repeats in its ECD and one cytoplasmic Toll/IL-1 receptor (TIR) domain (4). The ECD of human TLR4 shares approximately 25% aa sequence identity with other TLRs and 60%-74% aa sequence identity with bovine, equine, feline, mouse, rat, and porcine TLR4. The human MD-2 cDNA encodes a 160 aa precursor with an 18 aa signal sequence (5). Human MD-2 shares 20% aa sequence identity with MD-1 and 62%-64% aa sequence identity with bovine, mouse, and rat MD-2. MD-2 associates with TLR4 on monocytes, macrophages, dendritic cells, and B cells (5-7). MD-2 expression is required for cell surface localization of TLR4 and for optimal LPS-induced TLR4 signaling (7, 8). MD-2 also forms soluble disulfide-linked homo-oligomers which can interact with TLR4 (6). Through a domain separate from its TLR4-binding domain, MD-2 extracts LPS from circulating CD14-LPS complexes and carries the LPS into a ternary complex with TLR4 (9-11). The interaction of MD-2/LPS with TLR4 induces receptor oligomerization and the triggering of an inflammatory response (12). Increased levels of plasma MD-2 in septic shock patients sensitizes MD-2 non-expressing epithelial cells to LPS and promotes widespread tissue inflammation (13).

Product Datasheets

Related Research Areas

• B Cell Markers
• Common Macrophage Markers
• Diabetes
• IL-1 Family
• Immune Regulatory Molecules on Endothelial Cells
• Infectious Diseases
• Inflammatory Mediators
• Microglia Activation
• NFkB Pathway
• NOD-like Receptors and the Inflammasome
• Obesity
• Pattern Recognition Receptors
• Platelet Immune Receptors
• Regulatory T Cells (Tregs)
• T Cell Antigen Recognition
• Toll-Like Receptors
• Uptake of Amyloid beta by Glia Cells
• Uptake of Amyloid beta by Macrophages