Interfacial instability and membrane internalization in human erythrocytes heated in the presence of serum albumin.

The dynamics of morphological change, when human erythrocytes are heated through the spectrin denaturation temperature in the presence of bovine serum albumin, has been studied using differential interference contrast optics and a television video analysis system. Most washed (control) cells developed a wavy disturbance, with an average of 6.6 +/- 0.4 (2 S.E.) waves per cell rim, when heated. The average number of waves per cell rim decreased and the percentage of heated cells showing morphological changes in the dimple region increased with increasing serum albumin concentration, reaching 100% at 1.0 g/l. The change in the dimple region of cells heated in the presence of serum albumin involved the growth of a regular wavy disturbance around the cell dimple rim. The development of the wavy disturbance on the dimple, which resulted in the internalization of membrane, has been examined as an example of an interfacial instability on a biological membrane. Scanning and transmission electron micrographs confirm membrane internalization.