title: Stress as a determinant of saliva-mediated adherence and coadherence of oral and nonoral microorganisms.
abstract: OBJECTIVE
  The mucosal secretory proteins, such as the salivary proteins, play a key role in the acquisition and regulation of the mucosal microflora. Most notably, some microorganisms utilize the host's secretory proteins to adhere to the mucosa; a first step in colonization and infection. The secretory proteins also influence colonization by affecting the binding among microorganisms, a process denoted as coadherence. Previously we reported that acute stressors cause specific changes in saliva composition. The present study investigated to what extent these changes influence saliva-mediated microbial adherence and coadherence (ex vivo).
  
  
  METHODS
  Thirty-two male undergraduates provided unstimulated saliva before and during a control condition and two stressors: A memory test and a surgery video presentation. We used saliva-coated microplates to test the adherence of bacteria for which the oral cavity is either a natural reservoir (eg, viridans streptococci) or a portal of entry (eg, Helicobacter pylori). We also tested the saliva-mediated co-adherence between Streptococcus gordonii and the yeast Candida albicans. Correlation analyses were performed to determine the relationships between changes in microbial adherence and the concentrations of potential salivary ligands, viz. cystatin S, the mucins MUC5B and MUC7, S-IgA, lactoferrin, alpha-amylase, and total salivary protein.
  
  
  RESULTS
  During the memory test, saliva-mediated adhesion of Streptococcus sanguis, Streptococcus gordonii, and H. pylori increased, whereas the coadherence of C. albicans with S. gordonii decreased. During the surgical video presentation the saliva-mediated adherence of H. pylori, S. sanguis, and Streptococcus mitis increased. These changes were independent of salivary flow rate, but correlated with specific changes in salivary protein composition.
  
  
  CONCLUSIONS
  The results show that even moderate stressors, by altering the activity of the mucosal secretory glands, may affect microbial colonization processes such as adherence and coadherence. This study hereby presents a mechanism by which stress may affect the mucosal microflora and susceptibility to infectious disease.
authors.affiliation: Department of Dental Basic Sciences (J.A.B, M.T., K.N., E.C.I.V., A.V.N.A), Section Oral Biochemistry, Academic Centre for Dentistry Amsterdam, Amsterdam, The Netherlands.
authors.forename: Jos A
authors.initials: JA
authors.lastname: Bosch
authors.forename: Marjolein
authors.initials: M
authors.lastname: Turkenburg
authors.forename: Kamran
authors.initials: K
authors.lastname: Nazmi
authors.forename: Enno C I
authors.initials: EC
authors.lastname: Veerman
authors.forename: Eco J C
authors.initials: EJ
authors.lastname: de Geus
authors.forename: Arie V
authors.initials: AV
authors.lastname: Nieuw Amerongen
mesh_terms: D000328:Adult; D001422:Bacterial Adhesion; D002176:Candida albicans / Q000187:drug effects* / Q000502:physiology; D003773:Dental Plaque / Q000382:microbiology; D016480:Helicobacter pylori / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008297:Male; D009055:Mouth / Q000382:microbiology; D011598:Psychoneuroimmunology; D012463:Saliva / Q000737:chemistry / Q000502:physiology*; D012471:Salivary Proteins and Peptides / Q000032:analysis; D013291:Streptococcus / Q000187:drug effects* / Q000502:physiology; D034361:Streptococcus mitis; D013298:Streptococcus sanguis / Q000187:drug effects / Q000502:physiology
chemical_list: D012471:Salivary Proteins and Peptides