LC3B (Microtubule-associated protein 1A/1B-light chain 3B) is a critical biomarker for studying autophagy, a cellular self-degradation process that maintains homeostasis. As a mammalian homolog of yeast Atg8. LC3B exists in two forms: cytosolic LC3-I and lipidated LC3-II, which integrates into autophagosome membranes during autophagy. LC3-II formation is a hallmark of autophagosome maturation, making it a key target for monitoring autophagic activity.
LC3B antibodies are widely used to detect and quantify autophagosomes via techniques like Western blotting, immunofluorescence, and immunohistochemistry. These antibodies distinguish between LC3-I (18 kDa) and LC3-II (16 kDa), with increased LC3-II levels or punctate staining patterns indicating enhanced autophagy. However, interpreting results requires caution, as LC3B accumulation may reflect either autophagy induction or impaired lysosomal degradation.
Researchers often combine LC3B detection with other autophagy markers (e.g., p62/SQSTM1) to assess autophagic flux—the dynamic process of autophagosome formation and degradation. LC3B antibodies are essential tools in studying autophagy-related diseases, including cancer, neurodegenerative disorders, and infections. Their specificity and reliability depend on experimental conditions, such as cell fixation methods and inhibitor use (e.g., bafilomycin A1 to block lysosomal activity).
In summary, LC3B antibodies provide critical insights into autophagy regulation and dysfunction, bridging molecular mechanisms to pathophysiological outcomes.