Human salivary immunoglobulin and antigen-specific antibody activity after tonsillectomy

The importance of the lymphoid tissue collectively known as Waldeyer's ring, which includes the palatine, lingual and nasopharyngeal tonsils, in the induction and contribution of specific antibody responses in human saliva is not clear. The purpose of this study was to determine whether salivary immunoglobulin A (IgA) levels differ in quantity and quality between subjects who have had a tonsillectomy and age, sex and race-matched controls. Parotid saliva, whole saliva, and blood serum samples were collected from 25 volunteer children who had undergone tonsillectomy (T-) within 6-14 months of sampling and from 25 age, sex and race-matched controls. The levels of total IgA (and subclasses) in saliva, and of antigen-specific salivary IgA and serum IgA and IgG antibodies to 4-9 relevant antigens were analyzed by ELISA. No significant difference was observed in the mean total IgA and IgA subclass levels in parotid and whole saliva, although the mean levels for children with a T- were slightly lower. Children with a T- had significantly higher parotid salivary IgA and IgA1 specific/total activity than controls. The total and specific whole saliva IgA and the specific serum IgA or IgG activities were not significantly different from controls. These results indicate an association between the removal of tonsils and increased levels of specific IgA activity in parotid saliva within the first year after a T-.