Fibers, crystals, and other forms of HbS polymers in deoxygenated sickle erythrocytes

Abstract

We have examined by electron microscopy the formation of fibers and crystals from sickle hemoglobin within sickle erythrocytes following deoxygenation during capillary storage from 1 to 132 days. Intracellular fibers were found on the first day and throughout the period of study. The fibers exhibited a diameter (mean +/- SD) of 17.4 +/- 0.62 nm and were aligned in the cell with a fiber-to-fiber spacing of 18.6 nm (x-axis) by 22.7 nm (y-axis). Between 65 and 132 days, extracellular hemoglobin crystals developed, with a lattice periodicity of 9.63 +/- 0.6 nm. Fibers and crystals coexist as separate structures. These results suggest that crystal formation upon storage of packed deoxygenated sickle erythrocytes may proceed via a phase of fiber dissolution followed by hemoglobin reassembly into extracellular crystals, rather than by a progressive alignment and direct fusion of existing fibers.

Sickle Cell Anemia: Conclusions from a Forensic Case Report of a Young African Woman Who Died After Anesthesia

“…After nucleation, which depends on the 10th power of HbS concentration (i.e., an increase from 86 to 87 g=L would result in a more than a 12% increase of the effective concentration), fibrillar strands are formed that have been clearly demonstrated in the present case. Similar light and electron microscopic studies of sickle cells are known [9][10][11][12][13][14]. It is obvious that in the present case, anesthesia and=or surgery caused a fatal reduction of the ratio of HbS gelation delay time=capillary transit time of erythrocytes.…”

Mapping the entry of reactive oxygen metabolites into target erythrocytes during neutrophil‐mediated antibody‐dependent cellular cytotoxicity

“…We found that sickle cells were a good model for mapping oxidative reactions of hemoglobin. Since many of a sickle cell's hemoglobin molecules are in the form of long fibers (Carragher et al, 1988a,b;Kaperonis et al, 1986), their diffusion coefficient becomes negligible. Sickle cells were opsonized with rabbit anti-human erythrocyte IgG and then deoxygenated by bubbling N, through the cell suspension.…”

Structure of a crystal form of human methemoglobin indicative of fiber formation

“…It has been noted that sickle-cell hemoglobin fibers are frequently polymorphic (Finch et al, 1973;Ohtsuki et al, 1977;Magdoff-Fairchild & Chiu, 1979;Kaperonis et al, 1986;Mu & Magdoff-Fairchild, 1992;Wang et al, 2000), which suggests that the fiber structure may be variable or ill-defined or that it consists of more than one component. There is also evidence that structural transformations may occur in the filaments making up sickle fibers as a consequence of time or other physical factors (Magdoff-Fairchild & Chiu, 1979;Kaperonis et al, 1986;Mu & Magdoff-Fairchild, 1992).…”

“…There is also evidence that structural transformations may occur in the filaments making up sickle fibers as a consequence of time or other physical factors (Magdoff-Fairchild & Chiu, 1979;Kaperonis et al, 1986;Mu & Magdoff-Fairchild, 1992).…”