Rh Factor: Prevention of Isoimmunization and Clinical Trial on Mothers

Abstract

The results on the use of gammaG-immunoglobulin to Rh factor for the prevention of active immunization of Rh-negative mothers at risk appear most promising. One hundred and seven mothers in the clinical trial have been followed for periods of about 6 months to 1(1/2)12 years after delivery. Of these, 48 were treated mothers who received 5 ml gammaG-immunoglobulin to Rh, and 59 were untreated mothers. Of the 48 treated mothers none are actively immunized; seven of the 59 control mothers have become actively immunized to Rh.

Antibody-Mediated Immune Suppression of Erythrocyte Alloimmunization Can Occur Independently from Red Cell Clearance or Epitope Masking in a Murine Model

“…Since that landmark discovery, AMIS effects have been observed with a large number of cellular and other particulate Ags (4,27). In terms of the immune response to D + erythrocytes, the ability to prevent this response in humans has been achieved with both intentionally immunized males as well as during pregnancy (1,10,42). In the case of anti-D prophylaxis, considerable interest has been shown in replacing anti-D with a mAb.…”

The Structure and Function of the Rh Antigen Complex

“…By the 1960's, a mere 20 years after the discovery of Rh incompatibility, HDN due to anti-D could be effectively prevented. 2,3 The Rh system has long been known to be one of the most complex blood group systems. In addition to the presence or absence of the D antigen, other common Rh antigens include the allelic C or c, and E or e. However, over fifty different Rh antigens have been identified by investigating the specificity of antibodies produced after blood transfusion or pregnancy.…”

The Suppression of Rh Immunization by Passively Administered Human Immunoglobulin (IgG) Anti-D (Anti-Rh ∘)

“…There is a report that this occurred in humans following the injection of serum containing anti-D (anti-Rho) saline agglutinins (Clarke et al, 1963) and it is now thought that enhancement was due to the presence of the IgM anti-D (anti-Rho). Experimental work carried out in New York (Freda et al, 1966) and London (Mollison, unpublished observations) suggests that there is no enhancement when IgG anti-D (anti-Rho) is injected in doses too low to bring about immune suppression, although this has yet to be established with certainty.…”

“…The interval between doses depends on the response of the recipient (Freda et al, 1966). If a volunteer has not developed antibodies by 6 months after the first dose of antigen, a second dose of 5 ml of cells should be given.…”