Immunoglobulins in Umbilical Cord Plasma III: Haemolytic Disease of Newborn and Respiratory Distress Syndrome

In a study of the serum proteins in respiratory distress syndrome of the newborn (RDS), Hardie, Heese, and Kench (1965) found that the concentration of electrophoretically separated y-globulin was significantly reduced below the levels normally found in umbilical cord blood, and fell even further in the first few days of life. Later, Hardie and Kench (1967) demonstrated reduced concentrations of y-globulin also in the serum of mothers whose infants developed RDS. Low levels of y-globulin were demonstrable in the mother's plasma throughout pregnancy from about the 16th-20th week of gestation, and rose to normal about 6 weeks after delivery. One suggestion of the authors was that RDS might have an immunological basis, and they showed similar low concentrations of y-globulin in the umbilical cord sera of 3 infants with haemolytic disease of the newborn. Stemnberg, Dagenais-Perusse, and Dreyfuss (1956) had previously shown that the ratio of fetal to maternal y-globulin concentration was lower in infants with haemolytic disease than in normal infants. Similarly, Nejedld (1967) found that the titres of various antibodies acquired transplacentally as well as the y-globulin concentration were low in infants with haemolytic disease before exchange transfusion, and that those infants who had exchange transfusions showed falling concentrations of yglobulin and impaired 7S-antibody production for some months after birth. These previous investigations suggest that the total plasma y-globulin concentration may be abnormally low in haemolytic disease of the newborn and in RDS, and that in the former the immune response may be impaired for some months if replacement transfusion is carried out. An investigation is reported here in which the concentrations of the individual plasma immuno-