QUANTITATION OF IGA AND IGM IN UMBILICAL CORD SERUM OF NORMAL NEWBORN INFANTS

Electroimmunodiffusion has been used tomeasure immunoproteins in various biologic fluids. During a period of 4 months, electroimmunodiffusion was used to quantitate concentrations of IgA and IgM in serum collected from the umbilical cords of 97 unselected newborn infants. All samples contained IgM, ranging from 1.7 to 18.6 mg. per 100 ml. with a mean of 9.8±4.5 mg. per 100 ml. Detectable IgA, ranging from 0.5 to 5.8 mg. per 100 ml. with a mean of 2.6±1.7 mg. per 100 ml., was found in 29.9 per cent of the specimens. These data suggest that the fetus is capable of synthesizing IgA and IgM, and that they are present in concentrations which can be measured by sensitive immunochemical techniques. © 1969 The C. V. Mosby Company.