Erythroid and Megakaryocytic Differentiation

Question 1

In the erythroid series blasts are positive for what markers?

Answer 1

(+)
- CD34, CD38, CD45, CD117, and HLA-DR (moderate)

Question 2

What marker is progressively lost by the erythroid precursors?

Answer 2

• they lose CD45

Question 3

What markers are positive in pro-erythroblasts?

Answer 3

(+)
- CD36, CD38, CD45, CD71, CD117
- CD235a (Glycophorin A) dim
- HLADR moderate
*some may express CD34

Question 4

What markers are positive in basophilic erythroblasts?

Answer 4

(+)
- CD36, CD71, glycophorin (CD235a, bright)
- HLA-DR dim

Question 5

What markers are expressed by polychromatophilic and orthochromatophilic erythroblasts?

Answer 5

(+)
- CD36, CD71 and glycophorin bright

Question 6

What is the immunophenotype of megakaryoblasts?

Answer 6

(+)
- CD45, CD34, CD38, HLA-DR(dim) and CD117

Question 7

What change in marker expression is seen as megakaryocytic mature?

Answer 7

• become positive for CD61
• lose expression of HLA-DR, CD34 and CD117

Question 8

Other than CD61 what other markers are megakaryocytes positive for?

Answer 8

• CD41, CD42, and CD29

Question 9

What markers are seen on platelets?

Answer 9

(+)
- CD41, CD61, and CD29

(-)
-CD45 and CD38