ABSTRACT
This paper is concerned with quantitative aspects of the fragmentation of red cells by heat and of the haemolysis which accompanies it. The former process involves a splitting of the cell into fragments which retain, at least in part, some of the properties of the intact cell (ability to swell in hypotonic media, ability to undergo certain shape transformations, etc.; see Ponder, 1949). The latter process results in the formation of ghosts with properties which vary with the haemolytic system ; in some systems, the cell becomes a ghost by an all-or-none process (as in hypotonic systems containing cells in low volume centration, see Parpart, 1931), while in other systems the ghosts are partially haemoglobinized and partially rigid. To describe the phenomena adequately, it is accordingly necessary to consider the transition of the red cell to the ghost as a process which can occur in several ways in addition to the all-or-none escape of Hb and the replacement of the cell by an unsubstantial ghost ; it is all the more important to do this because evidence is accumulating that red cell ghosts in several kinds of haemolytic system possess both shape and rigidity (Ponder, 1942, 1950, Lindemann, 19490a,b).
The shaking mechanism was made for me by Mr Paul Cutajar of New York University Machine Shop. A convenient form of thermoregulator is one of a bimetallic type which can be quickly adjusted to any temperature over a wide range, and which operates without a relay.
Increases in the volume of intact red cells as a result of heating have not been considered in the foregoing discussion. In some systems these are not only noticeable, but troublesome, systems containing heated cells giving greater values of ρ than otherwise identical systems containing unheated cells, even when some lysis occurs in the heated systems. This effect can be minimized by using as ρ0 the volume concentration for a system which has been heated to a temperature a few degrees below T0,F and then plotting ρ against p, as above.
