• There are no granules in the cytoplasm of red cells.
• The cytoplasm in younger cells is extremely basophilic and becomes more lavender tinged as hemoglobin is synthesized.
• Size decreases as the cell matures.
• Nuclear chromatin material becomes more condensed in preparation for extrusion from the nucleus.
• The N:C ratio decreases as the nuclear material becomes more condensed and smaller in relationship to the entire red cell.
In the bone marrow and in the peripheral smear, each of these clues is helpful in enabling the technologist to stage a particular red cell. Identification of immature red cells should be systematic and based on reliable morphological criteria. Each red cell maturation stage will be described using size, N:C ratio, nuclear chromatin characteristics, and cytoplasm descriptions. N:C ratio implies the amount of nucleus to the amount of cytoplasm present; the higher the N:C ratio, the more immature is the cell. Nuclear chromatin will be described with respect to chromatin distribution, chro-matin texture, and color.
Pronormoblast (Fig. 3.2)
Size: 18 to 20 pm, the largest and most immature, the "mother cell"
Nuclear chromatin: Round nucleus with a densely packed chromatin, evenly distributed, fine texture with deep violet color, nucleoli may be present but are hard to visualize
Cytoplasm: Dark marine blue definitive areas of clearing
Was this article helpful?