CD71

Summary

CD71 has value in the recognition of erythroid differentiation in AML where expression levels can be strong. However, it is not fully specific and may also be a maker of high levels of proliferation. Expression is frequent on other AML subtypes including APL and other lineages including cases of ALL. For this reason the marker can suport a diagnosis of erythroid differentiation but should not be considered as fully specific.

Background

CD71 is the receptor for transferrin that is required by proliferating cells, but particularly by early erythroid cells (ofetn being lost as the cells mature). It can be helpful in histology of bone marrow since expression is acquired before CD235 (Gycophorin A) and is lost as the cells mature. It has value in recognising AML with erythroid differentiation, particularly if expression is strong, but is present on other subtypes so should not be regarded as specific.

Diagnostic Use

• Although there are relatively few studies it is clear that strong expression of CD71 may indicate erythrid differentiation of blast cells
• However there is reported expression at lower levels on other AML types, and less frequently on ALL nd MPAL cells so interpretation requires care

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