The Physical State of Hemoglobin in Sickle-cell Anemia Erythrocytes in Vivo

Venous blood removed anaerobically from patients with sickle-cell anemia was transferred immediately into fixative, thus precluding significant loss or gain of oxygen by the cells. Electron microscopy demonstrated an intraerythrocytic fibrillar fine structure similar to that described in prior studies on erythrocytes sickled by deoxygenation in vitro. Observations reported here lead to these conclusions: (a) explanations of the sickling process derived from in vitro experimentation may with validity be applied to sickling in vivo; and (b) the term "sickled" must be used with caution: a sickle-shaped membrane does not necessarily endose Hb S in filamentous form.