HSPA5. also known as GRP78 or BiP, is a member of the heat shock protein 70 (HSP70) family encoded by the *HSPA5* gene. Primarily localized in the endoplasmic reticulum (ER), it functions as a critical chaperone protein facilitating protein folding, assembly, and quality control under normal conditions. During ER stress, HSPA5 dissociates from ER stress sensors (e.g., PERK, IRE1. ATF6) to activate the unfolded protein response (UPR), a adaptive mechanism to restore cellular homeostasis. Dysregulation of HSPA5 is implicated in various diseases, including cancer, neurodegenerative disorders (e.g., Alzheimer’s, Parkinson’s), and viral infections, where it often supports cell survival by mitigating stress or promoting viral entry (e.g., SARS-CoV-2).
HSPA5 antibodies are essential tools for studying its expression, localization, and interactions in both physiological and pathological contexts. They are widely used in techniques like Western blotting, immunohistochemistry, and immunofluorescence to investigate ER stress pathways, cancer progression (e.g., tumor cell survival, drug resistance), and neurodegenerative protein aggregation. Commercial HSPA5 antibodies are typically raised against specific epitopes, with validation in multiple applications. Recent research also explores HSPA5 as a therapeutic target or biomarker, highlighting its dual role in cellular protection and disease mechanisms.