Mallory bodies

Mallory bodies are intracytoplasmic hyaline inclusions found in the liver cells of individuals with certain liver diseases. They were first described by the American pathologist Frank Burr Mallory in 1911, hence the name. Mallory bodies are also known as Mallory-Denk bodies (MDB), alcoholic hyalin or Mallory's hyaline.

Composition

Mallory bodies are composed of misfolded and aggregated proteins, including ubiquitin, keratin 8 and 18, and the chaperone protein heat shock protein 70 (HSP70). The exact composition can vary depending on the underlying disease process.

Pathogenesis

The formation of Mallory bodies is thought to be a response to cellular stress, such as oxidative stress or protein misfolding. The accumulation of these proteins may be due to a defect in the cell's protein degradation machinery, specifically the proteasome system. This leads to the aggregation of proteins, forming the characteristic Mallory bodies.

Clinical significance

Mallory bodies are a histological hallmark of several liver diseases, including alcoholic liver disease, non-alcoholic fatty liver disease (NAFLD), and hepatocellular carcinoma (HCC). They are also seen in certain rare genetic disorders, such as Mallory-Weiss syndrome and Wilson's disease. However, the presence of Mallory bodies alone is not diagnostic of any specific disease, and their clinical significance is still a subject of ongoing research.

See also

• Liver disease
• Protein aggregation
• Protein misfolding