Disk-Sphere Transformation in Mammalian Red Cells

1. Experimental evidence has been presented to show that the sphering of mammalian red cells in saline suspension between new slide and cover-glass is a result of these two changes: (1) the p H of the suspension is raised over 9.2 by the alkaline effect of the glass; (2) the glass adsorbs out from the suspension a protein, which, if present, prevents sphering until a p H of about 11.3 is reached, but if absent allows sphering around a p H of 9.2. 2. Anti-sphering factor is contained by both serum and cells. It cannot be adequately removed from cells by washing them with saline, but it can be removed from them by absorption on clean glass surfaces. 3. Changes of cell shape occurring between slide and cover-glass may be duplicated in the bulk of a suspension. 4. The p H and amount of anti-sphering factor present also influence the intermediate crenated shapes between the disk and sphere shapes. 5. Substances from the skin which counteract the activity of the anti-sphering factor may be introduced into a suspension by shaking it against the palm of the hand. Oleic or palmitic acids in a suspension also counteracts the activity of the anti-sphering factor present. 6. Watery ghosts show a peculiar temporary sphering between new slide and cover-glass. 7. The disk-sphere transformation in the absence of anti-sphering factor is reversible. In repeated reversing of the transformation the biconcavities and particular crenations of any one cell always reappear on the same parts of the surface of that cell.