Differentiation of Blood Groups in Dogs Based on Antigenic Complexes Present in the Erythrocytes. ∗

Abstract

When dogs are subjected to prolonged, intensive plasmapheresis, the hematocrit values tend to fall to anemia levels in spite of the

reinjection of the cells removed in the bleedings of the previous days. To compensate for this destruction of erythrocytes in vivo, it is necessary to inject periodically red blood cells obtained from donor animals. Although dogs are generally compatible with each other as regards blood transfusions 1 and this is evidenced by successful initial injections of cells, subsequent transfusions may create a sensi-tization which renders the donors incompatible thereafter. 2 3 4-5 The development of isoagglutinins and isohemolysins results in the production of an intense hemoglobinuria; the continuation of the cell infusions, spaced from 7 to 10 days apart, is followed by symptoms of profound shock.

It was suggested 3 that the development of this incompatibility is due to a common mechanism—a sensitization induced in the recipient by repeated injections of an antigen in the red blood cells of the donor. The evidence for this belief may be summarized as follows:

(1) The clinical picture of the reaction obtained in our dogs is characteristic of anaphylactic shock in that species.

(2) With the lapse of time (5 to 10 weeks) there is a restoration of compatibility. However, in this condition the sensitiveness may easily be made manifest again within one week by injection of the antigen.

(3) The incompatibility is “one-sided” in that the sera of the recipients agglutinate and hemolyze the cells of the donors, whereas cells of the recipients are compatible with the sera of the donors.

(4) The incompatibility can be passively transferred to a normal non-sensitized dog.

(5) Finally, the sensitized animals when in shock respond immediately and favorably to the intracardiac administration of adrenalin.

When the sera of the sensitized dogs were subjected to micro-agglutination tests in vitro, employing the cells of 36 dogs chosen at random, we noted that approximately 50% of these animals were incompatible with the sensitized dogs although none of the entire group had ever served as donors.