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Extramedullary Hematopoiesis (EMH)

The Digitized Atlas of Mouse Liver Lesions

Much of the work carried out by DTT is in support of the National Toxicology Program (NTP), an interagency partnership of the Food and Drug Administration, National Institute for Occupational Safety and Health, and NIEHS.

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Extramedullary hematopoiesis (EMH) can occur in the liver, especially when there is long-standing anemia. Typical morphological features consist of small aggregates of cells with intensely basophilic nuclei (erythroid) or small collections of immature and mature myelocytic cells (myelopoiesis) located in the sinusoids and, in severe cases, in portal areas.

Extramedullary hematopoiesis characterized by small aggregates of immature erythroid cells.

Multiple aggregates of neutrophilic band cells and erythroid precursor cells are present in the sinusoids with a large aggregate in a portal area.

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