Anti-IL-21 Rabbit Monoclonal Antibody for WB, IF/ICC, IF-P, ELISA - Q9HBE4

Core Product Specifications and Parameters

Biological Background: IL-21 Function and Localization

• Interleukin-21 (IL-21), also known as Za11, is a secreted cytokine encoded by the IL21 gene (Gene ID: 59067) in humans.
• IL-21 acts as a key immunoregulatory cytokine that bridges innate and adaptive immunity by promoting the production of IgG1 and IgG3 in B-cells and driving the generation and maintenance of T follicular helper (Tfh) cells and germinal center formation.
• In synergy with IL15 and IL18, IL-21 stimulates interferon-gamma (IFN-γ) production in T-cells and natural killer (NK) cells, enhancing cellular immune responses. Related references: PMID:11081504, PMID:15178704
• IL-21 also plays a role in the proliferation and maturation of NK cells when combined with IL15, and may regulate the proliferation of mature B- and T-cells upon activation.
• During T-cell-mediated immune responses, IL-21 may inhibit dendritic cell (DC) activation and maturation, contributing to immune regulation.
• The protein is predominantly expressed in activated CD4-positive T-cells and is secreted into the extracellular space, consistent with its cytokine function.
• IL-21 is subject to alternative splicing and contains disulfide bonds and glycosylation sites, and is associated with immune-related disease variants (keyword: CVID11).

Experimental Guidance and Technical Tips

• For Western blotting, expect a band at 18–19 kDa. Use reducing conditions and validate with positive controls such as stimulated T-cell lysates.
• In immunofluorescence (IF/ICC, IF-P), optimal staining may require permeabilization and fixation optimization; test on activated T-cells or relevant tissue sections.
• For ELISA applications, this antibody can be evaluated as a capture or detection reagent in sandwich ELISA setups for human or rat IL-21 quantitation.
• IL-21 is a secreted cytokine; consider using stimulation protocols (e.g., PMA/ionomycin) to enhance detection in cell-based assays.
• Confirm cross-reactivity in rat samples by comparing with known positive controls to ensure specificity.

CamelBio: Your One-Stop Sourcing Bridge

CamelBio streamlines IVD raw-material procurement by providing validated antibody pairs, optimized monoclonal and polyclonal antibodies, bulk ancillary reagents, and rare target sourcing. This anti-IL-21 monoclonal antibody is designed for researchers and diagnostic developers working on cytokine networks and immunological assays. With end-to-end supply support, CamelBio helps accelerate your projects from concept to clinic.