The absence of hemolytic disease in the newborn rhesus monkey (Macaca mulatta)

Hemolytic disease of the newborn has not been observed in rhesus monkeys even though the newborn's erythrocytes may be coated with maternal antibodies. Using a 51chromium-erythrocyte survival assay, we found that maternal antibodies do not mediate immune elimination of newborn's red blood cells. However, certain allogeneic or xenogeneic antibodies mediate clearance via sequestration by the reticuloendothelial system, or by intravascular hemolysis, or by a combination of these. The class of antibody plays a major role in elimination since red cells coated with IgG but not with IgM were rapidly cleared. In addition, the quantity of antibody controls the rate and extent of clearance. A comparison of rhesus alloantisera suggests that coating of multiple antigenic sites is necessary for clearance. Passive immunization with selected high-titered anti-erythrocyte alloantisera can induce some hematologic signs of erythrocyte destruction in newborn monkeys.