Abstract
In α-1-antitrypsin (AAT) deficiency, individuals homozygous for the AAT mutant Z gene
synthesize large quantities of mutant Z protein in the liver, which folds improperly
during biogenesis and is retained within the hepatocytes rather than appropriated
secreted. This accumulation of mutant Z protein triggers an intracellular injury cascade
causing cell death in the population of hepatocytes with the largest accumulations
of Z protein. Hepatocellular proliferation, hepatic fibrosis, and hepatocellular cancer
in some individuals can be the result. New insights from basic science studies have
now allowed the application of new biotechnologies to this previously untreatable
disease. Specifically, drugs designed to accelerate the intracellular removal of the
mutant Z protein (autophagy enhancers) and siRNA strategies designed to shut down
synthesis of the toxic, mutant Z protein, are now in human trials. Other approaches,
such as gene correction, cell therapy, and antifibrotic drugs are in preclinical development.
Keywords
alpha-1-antitrypsin - autophagy - liver disease - siRNA - endoplasmic reticulum-associated
degradation