Salivary-IgA antibody to glucosyltransferase of oral microbial origin in children.

Salivary IgA levels were measured in whole saliva of 143 children, 2-48 months of age. The median salivary IgA concentration of children less than 12 months old was 30 micrograms/ml. A significant increase in salivary IgA concentration occurred in children 12 to 17 months old. More than 50 per cent of the population, 36 months of age and older, had Streptococcus mutans (88 per cent biotype I) recoverable from their teeth. Salivary IgA antibody levels were measured by an enzyme-linked immunosorbent assay to glucosyltransferase (GTF) antigen complexes from oral streptococci. Salivary IgA antibody to GTF from Streptococcus sanguis was detected in many children. Over 40 per cent of the 43-48-month-old group had detectable salivary antibody to Strep. sanguis GTF; salivary IgA antibody to Strep. mutans GTF (biotype I) was less frequently detected. Most subjects with salivary antibody to Strep. mutans GTF had antibody to Strep. sanguis GTF but only 23 per cent with salivary antibody to Strep. sanguis GTF had antibody to Strep. mutans GTF. Antibody to Strep. sanguis GTF was infrequently associated with the recovery of Strep. mutans from the teeth.