Local production of rotavirus specific IgA in breast tissue and transfer to neonates.
Rotavirus specific IgA, secretory component, and IgG were measured by enzyme linked immunosorbent assay in 20 pairs of mothers and babies to estimate antibody transfer from the mother, particularly from breast milk to neonatal faeces. Colostrum contained high titres of specific IgA and secretory component, which decreased gradually. Faeces after breast feeding for three days showed detectable titres of IgA and secretory component, with further increases by seven days. There was a positive correlation between titres of secretory component in breast milk and in faeces. To clarify the mechanism of high anti-rotavirus activity in breast milk, ratios of rotavirus specific IgA in maternal serum samples to breast milk were calculated and compared with those that were herpes simplex virus specific. Significantly higher concentrations were obtained for the herpes simplex virus specific samples, indicating that anti-rotavirus IgA is selectively produced in breast tissue.