Anti-Human CD28 (3G5E) Antibody

This unconjugated mouse monoclonal antibody targets the human CD28 co-stimulatory receptor, a key surface molecule expressed on resting and activated T lymphocytes where engagement by B7 family ligands (CD80/CD86) provides the essential second signal for T-cell activation. Clone 3G5E has been validated for flow cytometry, immunohistochemistry on frozen tissue sections, immunoprecipitation, and functional T-cell co-stimulation assays, giving immunology researchers a versatile reagent for phenotyping, signaling studies, and activation readouts. The reagent reacts specifically with human CD28 and is supplied as 50 µl of liquid format in a buffered solution containing 150 mM NaCl, 100 mM KCl, and 50 mM sodium phosphate at pH 7.5, ready to use directly or after dilution in assay buffer. Host species is mouse, and the unconjugated format allows flexible secondary antibody pairing for immunofluorescence, chromogenic, or Western workflows. For storage, keep refrigerated in the provided buffer; aliquot and freeze if extended use is planned to limit freeze-thaw cycles. Researchers studying immune checkpoint biology, transplant immunology, autoimmune disease models, and CAR-T cell engineering will find this reagent useful for surface staining of primary human T cells and CD28-driven activation readouts. Each lot is supplied by Antibodies.com with consistent performance across the validated application panel.