Anti-Rb (phospho Thr821) Antibody [24A7]

The 24A7 monoclonal antibody from Antibodies.com selectively detects the retinoblastoma tumor suppressor protein (Rb1) only when phosphorylated at threonine 821, a CDK4/6- and CDK2-driven cell cycle regulatory mark that rises during the G1/S transition. Supplied as a 100 µg liquid aliquot in a single vial, this unconjugated IgG1 reagent is validated for western blot and ELISA on human samples, giving researchers flexibility to pair it with their own HRP, biotin, or fluorophore-conjugated secondary antibodies. For western blot, a working concentration of 1–2 µg/mL is commonly applied to whole-cell lysates from cycling HeLa, A431, or MCF-7 cultures, where a band of approximately 110 kDa is expected. Aliquot upon receipt and store at -20°C, avoiding repeated freeze-thaw cycles to preserve phospho-specific binding activity. Recommended for research use only in studies of G1 checkpoint signaling, E2F pathway control, and oncology drug mechanism of action, including characterization of CDK4/6 inhibitor response in tumor cell models.