Anti-S100A9 Rabbit Polyclonal Antibody for WB, IHC-P, IF/ICC, ELISA - P06702

Core Product Specifications and Parameters

Biological Background: S100A9 Function and Localization

• S100A9 is a calcium- and zinc-binding protein of the S100 family, predominantly forming the calprotectin heterodimer (S100A8/A9) with broad intra- and extracellular functions in innate immunity. Related references: PMID:16258195 PMID:19122197 PMID:8423249
• Intracellularly, S100A9 facilitates arachidonic acid trafficking, modulates cytoskeleton dynamics during phagocyte migration, and activates NADPH oxidase by promoting enzyme complex assembly and cofactor transfer. Related references: PMID:15331440 PMID:21325622 PMID:15642721 PMID:22808130
• As a secreted DAMP/alarmin, it binds TLR4 and AGER, triggering MAPK and NF-κB pathways to amplify pro-inflammatory cytokine production and leukocyte recruitment. Related references: PMID:19402754 PMID:22804476 PMID:15598812 PMID:21487906
• S100A9 exhibits direct antimicrobial activity against bacteria and fungi through zinc chelation and enhances neutrophil bactericidal functions by promoting chemotaxis, phagocytosis, and degranulation. Related references: PMID:19087201 PMID:12626582 PMID:15331440 PMID:20103766
• S100A9 regulates cell survival and death: it exerts anti-apoptotic effects via ITGAM/ITGB and TLR4/MEK-ERK signaling, and can induce autophagy or apoptosis through ROS and BNIP3. Related references: PMID:22363402 PMID:19935772
• The protein acts as an oxidant scavenger to limit tissue damage and possesses transnitrosylase activity, mediating S-nitrosylation of targets like GAPDH in association with iNOS. Related references: PMID:21912088 PMID:22489132 PMID:25417112
• Predominantly expressed in neutrophils and monocytes, calprotectin is strongly upregulated in inflammatory conditions and various tumors, and localizes to the cytoplasm, cytoskeleton, cell membrane, and is secreted.

Experimental Guidance and Technical Tips

• The immunogen is a synthetic peptide spanning residues 20–114 of human S100A9, a region conserved across human, mouse, and rat; cross-reactivity in these species should be validated in the relevant sample system.
• For Western blotting, consider a dilution range and appropriate protein loading to detect the ~13 kDa band; note the potential presence of higher-order complexes when analyzing calprotectin.
• In IHC-P and IF/ICC applications, optimize antigen retrieval and blocking conditions; the secreted and membrane-associated nature of S100A9 may require permeabilization steps.
• When using this antibody in ELISA, pair with a suitable capture antibody if developing sandwich assays for calprotectin quantification.

CamelBio: Your One-Stop Sourcing Bridge

CamelBio provides diagnostic manufacturers, laboratories, and research institutes with streamlined access to high-quality raw materials, including this anti-S100A9 polyclonal antibody for inflammation and cancer research applications. Our portfolio covers validated antibody pairs, optimized recombinant proteins, and bulk ancillary reagents, complemented by end-to-end technical support to accelerate your assay development. Whether you need standard catalog items or custom sourcing for rare targets, CamelBio bridges the gap from concept to clinical implementation.