Agglutinin and Acidic Proline-rich Protein Receptor Patterns May Modulate Bacterial Adherence and Colonization on Tooth Surfaces

Abstract

Bacterial binding to salivary proteins may in part account for individual differences in the colonization of tooth surface. High-motecular-weight glycoproteins, agglutinins, mediate S. mutans adherence, whereas acidic proline-rich proteins mediate adherence of other early-colonizing streptococci and Actinemyces. The aim of the present study was to examine the composition of adherence-related salivary proteins and dental plaque micro-organisms in three individuals with a low, moderate, and high capacity to mediate S. mutans adherence. The S. mutans (strain Ingbritt) binding activity resided with 300-kDa agglutinin which was six-fold more prevalent in the high S. mutans binding saliva compared with the low one. Binding to all three salivas was completely by a monoclonal anti-agglutinin antibody. The moderate S. mutans binding saliva was found to contain adherence-inhibiting components. Furthermore, the low and moderate S. mutant binding salivas mediated binding of A. naeslundii strain LY7 to a greater extent the saliva with high S. mutans binding. The A. naeslundii binding activity resided with the acidic proline-rich proteins (APRPS) and paralleled the relative content of 106- and 150-residue A-PRPS. Low A. naeslundii binding coincided with an almost two-fold higher ratio of 106/150 APRPs compared the high A. naestundii binding saliva. During conventional gel filtration, a degradation of the acidic, basic, and glycosylated proline-rich proteins was evident in the saliva with high S. mutatis and low A. naeslundii binding. This saliva donor had a comparably high rate of dental plaque formation, high counts of S. mutans, and low counts of other streptococci and Actinomyces.