Placental Transfer of Respiratory Syncytial Virus-Specific IgG in Iranian Mothers

Background: Respiratory Syncytical virus infection is the most common cause of bronchiolitis and viral pneumonia in infancy. Objective: To investigate the placental transfer of RSV-specific IgG in Iranian mothers. Methods: The antibodies were measured in sera of 146 mother/newborn pairs using a commercially available indirect Enzyme Linked Immunosorbent Assay (ELISA). The studied subjects were among healthy pregnant women who attended to the Zeinabieh Hospital of Shiraz University of Medical Sciences in a one year period. Results: A highly significant correlation was observed between RSV-specific IgG in newborns and mothers (r = 0.88). However, mean RSV-specific IgG antibodies in neonates was significantly higher than that of their mothers (P = 0.019). In addition, the mean cord/maternal ratio of RSV-specific IgG was detected to be 1.27 ± 0.60. Maternal blood group, age, parity, previous abortions and neonatal gestational age had no correlation with placental transfer of RSV-specific IgG antibodies. Conclusion: Our finding demonstrates that placental transfer of RSV-specific IgG antibodies is an active process and the main factor that influences this transfer is maternal concentration of these immunoglobulins.