The resistance to mechanical injury of the erythrocytes of different species

Abstract

As the first step in an analysis of the conditions under which red cells will survive in vitro, we have studied the effects of handling them, as in washing. That this may entail injury is suggested by the work of Meltzer, 1 who noted that a few minutes'shaking of whole blood hastens considerably the disintegration of the erythrocytes.

Our experiments show that in citrated plasma the red cells of the dog, rabbit, sheep and man withstand well the handling incident to ordinary washing. They may be centrifugalized and suspended again and again without hemolysis. The case is entirely different when cells in salt solution are repeatedly washed and suspended. Except in the case of human cells this entails marked injury, which expresses itself either in an immediate slight hemolysis, or more often in a shortening of the time during which the cells remain intact.

The protective action of plasma, even when dilute, is well shown when washed cells are suspended in it and in isotonic salt solution, and shaken. Hemolysis occurs much sooner in the salt solution. The experiments have brought out striking differences in the fragility of the red cells of different species—and, to a less degree, of different individuals. Dog cells shaken in the salt solution undergo a marked and almost immediate hemolysis. Rabbit corpuscles are somewhat less sensitive, and sheep corpuscles even less so, while the red cells of man are markedly resistant, though in their case, too, the protective action of plasma can be demonstrated.

The resistance of the red cells to mechanical injury has little if any relation to their resistance to hypotonic salt solution. For example, the corpuscles of the dog, though much more easily destroyed by shaking than those of the sheep, will withstand a hypotonic salt solution in which the laking of sheep cells is pronounced.