Detection of cell surface determinants for anti-Leu M3 (CD14), MY9 (CD33) and MY4 (CD14) and phagocytic function of cord blood monocytes in the course of gestational age.
To investigate immunological functions of cord blood cells, cord blood monocytes of 84 term and preterm newborn infants were examined in presenting cell surface determinants for the monoclonal antibodies anti-Leu M3 (CD14), My9 (CD33) and My4 (CD14) using an alkaline-phosphatase-anti-alkaline-phosphatase staining method. We also tested the phagocytic function of these cells by incorporation of Candida albicans in a 60 min incubation assay. Mean values for antigen expression ranged from 60 to 70%, whereby My4 showed a statistically significant higher level compared to Anti-Leu M3 and My9 (P = 0.05). Changes of antigen expression were statistically significant by the time of maturation. Statistically significant differences between male and female newborns were observed in 26-33 and 36-37 weeks of gestation. Considering the modus of delivery, no significantly higher amount of antigen-presenting monocytes were found in newborns of spontaneous birth compared to cesarean sections. However, no statistically significant differences in phagocytosis were observed between term and preterm newborn infants, mature newborns showed higher levels of both antigen expressing and phagocytic monocytes in contrast to a higher number of phagocytic cord blood monocytes only in premature infants.