Antemortem Basopenia as an Index of Resistance.

Abstract

In a recent study of rabbit's blood 1 it was shown that the basophile level before inoculation seemed to bear some relation to the course of infection with Treponema pallidum and it was suggested that the basophile count might be used as an index of the resistance of the rabbit to this disease. During the same period (1927-28-29) blood counts were made upon 44 rabbits within 10 days before death, and it was found that all except 3 had both an absolute and relative basopenia. This agreed with the previous association of low blood basophiles with low resistance and high blood basophiles with high resistance. The rabbits were the fatal cases in the groups used for diverse experiments in which antemortem counts were made and represent approximately 20% of the total number of animals used. 32 of the 44 died from the effects of a transplantable neoplasm and the remaining 12 from other causes. 8 of the 44 animals were killed when in a dying condition; the rest were found dead.

The differential counts were made with the neutral red supravital technic upon blood taken from a marginal ear vein. In all examinations at least 100 cells were counted. In the instance of the postmortem counts made on 2 tumor animals 5 minutes after death, the blood was taken from the heart and 400 white cells counted in the first animal and 600 in the second. Total white counts were made at the same time as the differential. Most examinations were made at regular intervals and the time between the last count and the animals' death varied from one to 10 days with an average of 2.3 days.

The average basophile count of 950² per cmm. of blood obtained from 11 10 counts upon 174 normal animals during the same period is used as a basis for comparing the results of the antemortem counts (Fig. 1).