Leucocytic iso-immunization in pregnancy

The results of a study on leucocytic iso-immunization in pregnancy and on the antibody characteristics of the sera produced are reported. The investigation was carried out on 774 puerperae, making use of the cytotoxicity reaction. The results may be summed up as follows: pregnancy constitutes an important cause of leucocytic iso-immunization; leucocytic iso-immunization may occur either in primiparae or multiparae, but the relation between the two iso-immunization percentages was not statistically significant; the lymphocytotoxis sera may show direct antibody specificity towards either the known antigens as listed in the Major Histo-compatibility System, or else antigens not yet defined; the spectrum of antibody specificity varies in relation to the temperature at which the reaction occurs but does not seem to be influenced significantly by the number of pregnancies; and the antibody specificities obtained do not always correspond to those expected on the basis of SD1 and SD2 phenotypes of women and their respective husbands.