Differentiation of salivary agglutinin-mediated adherence and aggregation of mutans streptococci by use of monoclonal antibodies against the major surface adhesin P1

Abstract

The ability to adhere to salivary agglutinin-coated hydroxyapatite beads and to aggregate in the presence of fluid-phase salivary agglutinin was tested by using 25 isolates of mutans streptococci representing eight serotypes. Both adherence and aggregation activity correlated with expression of the Mr-185,000 cell surface antigen P1 on Streptococcus mutans serotype c, e, and f strains. In addition, it was shown that the P1 molecule itself served as the adhesin of S. mutans serotype c, since adherence was significantly inhibited by the presence of recombinant-specified Mr-150,000 P1. The ability of S. sobrinus strains to adhere or aggregate did not correlate with expression of the P1 cross-reactive antigen SpaA. There was also evidence for interaction with salivary agglutinin, as manifested by aggregation but not adherence of S. rattus serotype b, which does not express a P1 cross-reactive antigen. To understand the interaction of Pl with salivary agglutinin at the molecular level, a panel of 11 anti-Pt monoclonal antibodies was tested for inhibitory activity in adherence and aggregation inhibition assays. Overlapping, but not identical, subsets of monoclonal antibodies were found to inhibit adherence and aggregation, indicating that the interactions of P1 with salivary agglutinin which mediate these two phenomena are different. The localization of functional domains of P1 which may mediate the aggregation and adherence reactions is discussed.

Deletion of gtfC of Streptococcus mutans has no influence on the composition of a mixed‐species in vitro biofilm model of supragingival plaque

“…1.0 ± 0.00 ns 11.9 ± 0.32*** 9.8 ± 2.53*** 4.0 ± 2.21*** -Four units at risk §Twelve fissures at risk Twenty units at risk ns, not significant; *** P < 0.001 SpaP into the medium instead of expressing the protein on their surface do not adhere well to saliva-coated hydroxyapatite (14). Streptococcus mutans UA159 and OMZ64 were not included in that study and their mode of SpaP expression remains unknown.…”

Adherence and internalization of Streptococcus gordonii by epithelial cells involves ?1 integrin recognition by SspA and SspB (antigen I/II family) polypeptides

“…This is in contrast to the observation by Chatenay-Rivauday et al (1998) that the V region alone from S. mutans AgI/IIf adhered to monocytes. The V region also appears to carry primary epitopes for adherence to salivary glycoproteins (Brady et al, 1992;Kelly et al, 1995). There may be sequences within the NA region that bind integrin directly, or the NA region may be required for functional conformation of the V region.…”

On the rôle of human salivary micelle‐like globules in bacterial agglutination

“…The present study focuses on streptococci. Numerous studies have demonstrated that along with the lactobacilli, the streptococci can produce the quantities of lactic acid necessary to demineralize teeth (22). It is therefore of interest to study the mechanisms by which these particularly cariogenic bacteria are dealt with by host defences.…”