Target cells, also known as codocytes, have the appearance of a target with a bullseye. Such cells are thin and have a disproportional increase in the surface membrane area to volume ratio. This increased ratio may result from an increase in membrane surface area or a decrease in hemoglobin content. Morphologically, target cells have a central, hemoglobinized area surrounded by an area of pallor. The periphery of the cell contains a band of hemoglobin. Target cells may appear in association with the following conditions:

• Liver disease
• Iron deficiency
• Post-splenectomy
• Decreased lecithin cholesterol acyltransferase activity
• Thalassemia (hemoglobinopathy)

Cell biology