A guide to selecting high-performing antibodies for Glucocorticoid receptor (UniProt ID: P04150) for use in western blot and flow cytometry

Inhaled corticosteroids are the cornerstone of asthma therapy, reducing airway inflammation, mucus hypersecretion, and bronchial hyperresponsiveness. These effects are mediated by the glucocorticoid receptor (NR3C1), which regulates anti-inflammatory gene transcription following activation. However, approximately 10% of patients are corticosteroid-refractory, highlighting the need for robust antibodies to accurately study receptor expression, localisation, and function. Here we systematically characterised twenty-two commercial antibodies for western blot and flow cytometry using a standardised knockout validation approach in human A549 cells, comparing readouts in an NR3C1 knockout line with its isogenic parental controls. These experiments form part of a broader collaborative initiative to address antibody reproducibility by characterising commercial antibodies for human proteins and making the results openly available to the community. While antibody use and protocol conditions vary between laboratories, this report provides a resource to guide the selection of suitable reagents for studies of the glucocorticoid receptor in health and disease.