FUT4

FUT4 catalyzes the synthesis of the non-sialylated antigen, Lewis x (CD15). It has been detected in human embryos (5-10 weeks) suggesting a role in development.

CD15 synthesis is directed by FUT9 (MIM.104230) in lymphoid cells and mature granulocytes and by FUT4 (MIM.606865) in promyelocytes and monocytes

CD15 is a carbohydrate adhesion molecule (not a protein) that mediates phagocytosis and chemotaxis.

Immunochemistry

 membranous labeling
 diffuse cytoplasmic or Golgi staining in classic Hodgkin lymphoma

Diagnosis

 Hodgkin lymphoma

• Reed-Sternberg cells

 help differentiate between classic Hodgkin lymphoma (CD15+) and anaplastic large cell lymphoma (usually CD15-)
 help differentiate between adenocarcinoma (CD15+) and mesothelioma (CD15-)

Positive immunostaining

 Reed-Sternberg cells (classic Hodgkin’s lymphoma and follicular Hodgkin’s lymphoma)
 15% of peripheral T cell lymphoma
 50% of carcinomas
 5% of B cell lymphomas

• some B-CLL
• some pre-pre B ALL
• some AML
• occasionally anaplastic large cell lymphoma (usually negative)

Negative immunostaining

 non-activated lymphocytes
 basophils
 platelets
 erythroid cells
 L& H cells in nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL)
 diffuse large B cell lymphoma
 granulocytic sarcoma
 systemic mastocytosis
 pleural epithelial mesothelioma
 hairy cell leukemia
 malignant meningioma
 malignant histiocytes
 Langerhans cell histiocytosis

See also

 CD15