CELLULAR AND IMMUNOGLOBULIN CONTENT OF NEONATAL MILK

Abstract

The cellular and immunoglobulin content of neonatal breast secretions from 12 full term infants less than 10 days post delivery was studied. Precision pipettes were used to aspirate the mammary gland secretion directly from the neonates cleaned nipple/areola skin surface. Cleaning was performed with sterile cotton and water and air dried. For measurement of the immunoglobulin concentration, direct innoculation of the neonatal milk into radial immunodiffusion plates, using the kailestad low level IgA, IgM, and IgG kit was performed. Cell viability was assessed using the trypan blue exclusion technique and the differential cell count was performed on a cytocentrifuged preparation following Wrights staining. Although cell viability was greater than 90 percent, fewer cells per ml of fluid were found in neonatal milk than are reported in mother's milk. The predominant cell types observed were lymphocytes and macrophages. The immunoglobulin content was predominantly IgG with minimal concentration of IgA, and no IgM detected. These data suggest similar but different cellular and immunoglobulin regulatory mechanisms in neonatal breast secretions as compared to mothers' milk and indicate a need for further study to determine the clinical significance of these observations.