[Quantitative estimation by ELISA of IgG anti-D (RH1) antibodies in immunoglobulin preparations and in the sera of immunized donors].
Immunoglobulin preparations of anti-D (RH1) are injected to prevent haemolytic disease of the newborn. Such preparations are obtained by the fractionation of plasma from immunized donors. Measurement of the concentration of IgG anti-D is required to estimate the potency of anti-D preparations and sera from immunized donors. We have developed an ELISA method for the quantification of IgG anti-D. This method included the following steps, sensitization of red cells by anti-D, solubilization of red cell membranes by Triton, and eventually, measurement of IgG anti-D concentration by ELISA. The international reference preparation of anti-D (68/419) was used as a reference. With this method, we measured IgG anti-D concentrations in 5 immunoglobulin preparations of anti-D and in the sera of 10 donors immunized by D antigen. The ELISA results were compared with those obtained by automated hemagglutination. A mean anti-D concentration of 56.2 micrograms/mL was found by ELISA in immunoglobulin preparations. Similar results were obtained by automated hemagglutination (mean 52 micrograms/mL). In the sera of 10 D-immunized donors, anti-D IgG concentration varied from 2.2 to 59.8 micrograms/mL. A good correlation between ELISA and automated hemagglutination was observed in these sera (r = 0.98, p < 10(-7)). In conclusion, the ELISA technique offers an alternative to automated hemagglutination. It requires only the standard equipment necessary for immuno-enzymatic methods.
Unité d'immunologie transfusionnelle, Institut national de la transfusion sanguine, 6, rue Alexandre-Cabanel, 75015 Paris, France. lambin@worldnet.fr
P
P
Lambin
M
M
Debbia
M
M
Béolet
Y
Y
Brossard
P Y
PY
Le Pennec
P
P
Rouger
D001782:Blood Donors; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D004910:Erythrocyte Membrane / Q000276:immunology; D006801:Humans; D007114:Immunization; D007074:Immunoglobulin G / Q000097:blood*; D007136:Immunoglobulins / Q000097:blood*; D007231:Infant, Newborn; D012204:Rh-Hr Blood-Group System / Q000276:immunology*
D007074:Immunoglobulin G; D007136:Immunoglobulins; D012204:Rh-Hr Blood-Group System