Anti-c-Rel (phospho-S503) Antibody

c-Rel is a member of the NF-κB family of transcription factors that regulates genes involved in immune cell differentiation, B- and T-cell activation, and inflammatory signaling. Phosphorylation at serine 503 is a post-translational modification tied to regulation of c-Rel activity and downstream transcriptional programs. This rabbit polyclonal reagent was raised against the phosphorylated S503 epitope and selectively recognizes the modified form of human c-Rel in research samples, supporting studies of NF-κB signaling dynamics, lymphocyte activation, and immune response pathways.

Supplied by Antibodies.com as a 100 µl aliquot at 1 mg/ml in phosphate buffered saline with 0.05% sodium azide at approximately pH 7.2, the antibody is unconjugated and validated for Western blot and immunohistochemistry workflows. Researchers apply it to investigate phosphorylation-dependent changes in c-Rel during B-cell maturation, cytokine signaling, and oncogenic contexts where NF-κB pathway activity is altered. The polyclonal format offers recognition of multiple epitopes surrounding the phospho-S503 site, which is useful when probing denatured targets on membranes or fixed tissue sections.

Because the reagent recognizes the phospho-S503 modification rather than total c-Rel protein, it is well suited to studies that track pathway activation over time, for example after cytokine stimulation, B-cell receptor engagement, or pharmacological inhibition of upstream kinases. Sodium azide in the formulation provides microbial protection for repeated use from a single vial, and the unconjugated format allows flexible pairing with secondary detection reagents of the researcher's choice.