Affiliations: Department of Oral Biology, Dental Research Center, Emory University, Atlanta, Georgia, USA
Note: [] Address reprint requests to: Dr. Richard L. Gregory, Dental Research Center, Emory University, Atlanta, GA 30322, USA. A version of this paper was presented at the First International Conference on Human Antibodies and Hybridomas, Orlando, FL, USA, 18–20 April 1990
Abstract: Previously, we reported that smokeless tobacco users have significantly higher levels of immunoglobulin A and J chain in whole saliva than non-tobacco users. Because there was no difference in levels of secretory component between the two groups, the proportion of secretory component/immunoglobulin A was significantly lower in users than non-users. There was no significant difference in antibody function. In the present study, we examined immunoglobulin A from whole saliva of users and non-users to determine the effect of smokeless tobacco on the ability of secretory component to bind to immunoglobulin A containing J chain. Whole saliva was passed over an affinity chromatography filter unit coupled with anti-α heavy chain-specific antibody followed by passage over a molecular sieve high-performance liquid chromatography column. Peaks were collected and examined for immunoglobulin A, J chain and secretory component by enzyme-linked immunosorbent assay. Saliva from users had three significantly larger peaks (3–4 fold) at 280 nm than non-users, confirming the presence of a higher concentration of immunoglobulin A in users. The secretory component/J chain and secretory component/immunoglobulin A ratios for the largest peak were significantly less in users. This indicates that smokeless tobacco has an effect on the ability of secretory component to bind to immunoglobulin A without a loss in antibody function. This may occur either prior to immunoglobulin A/J chain binding to secretory component receptors on secretory epithelial cells or internal to the epithelial cells. These studies provide further evidence for the role of secretory component in mucosal immunity.
Keywords: immunoglobulin A, secretory component, J chain, saliva, tobacco
