Figure 4.

Erythroid parameters. (a) Red cell morphology in blood from normal (left) and knockout (right) mice. Normal cells at left show the typical biconcave disk morphology, while homozygous 4.1-deficient red cells at right exhibit a more heterogeneous morphology marked by the presence of numerous cell fragments. Red cells from heterozygous mice were morphologically normal. (b) Red cell indices. Cell hemoglobin content and cell hemoglobin concentration histograms of whole blood from normal (upper panels) and knockout (lower panels) mice. The dark areas of the histogram represent reticulocytes, and the gray areas represent mature red cells. Significant numbers of fragmented red cells with decreased hemoglobin content (< 10 pg) can be seen in knockout mice. Cell dehydration is also a feature of knockout mice red cells, as indicated by the shift in hemoglobin concentration from reticulocytes (black area in lower right panel) to mature red cells (gray area in lower right panel). (c). Osmotic gradient deformability profiles of red cells from normal (+/+), heterozygous (+/–), and homozygous (–/–) 4.1R-deficient mice. The maximum value of the deformability index, a direct measure of red cell surface area, is reduced in (+/–) red cells and more dramatically reduced in (–/–) red cells.