[Immuno-elimination and clearance of Rh-positive erythrocytes in Rh-negative volunteers following administration of anti-D-immunoglobulin].

The prophylactic treatment of Rhesus-negative women to prevent Rhesus-sensitization has been accepted worldwide, although the working mechanism of the anti-D-immunoglobulin is still unknown. We have used Cr-51-labelled red blood cells to investigate the immune clearance of the cells in Rhesus-negative volunteers following injection of anti-D. Intravenous application of anti-D-immunoglobulin resulted in an accelerated elimination of the Rhesus-positive erythrocytes from the peripheral blood in contrast to the intramuscular treatment with the same dosage. But we had not been able to investigate whether the intravenous route might result in a more effective prophylaxis. In result of the application of IgG-anti-D sequestration can be observed in the spleen. This organ seems to be of great importance for the working mechanism of the anti-D-immunoglobulin. On the other hand splenectomized patients showed reduced clearance rates. In these cases the liver may be involved in the elimination of the red blood cells. F(ab')2-fragments, which cannot pass the placental barrier, seemed to be ineffective with respects to immunosuppression. As patients showing the Du-variant can be sensitized against -- D -- they also should receive anti-D-immunoglobulin for prophylaxis.