394 - Analysis of Novel Streptococcal Probiotic Candidates’ Antimicrobial and Anti-Inflammatory Properties

Saturday, May 27, 2023

10:40 AM – 10:55 AM

Location: Exhibit Hall

Has Audio

Presenting Author(s)

SA

Samuel L. Allen, BS

Dental Student
University of Iowa, Iowa City, IA
University of Iowa College of Dentistry
Coralville, Iowa, United States

Co-Author(s)

JB

Jeffrey A. Banas, PhD

Director, Iowa Institute for Oral Health Research
University of Iowa College of Dentistry, Iowa City, IA
Iowa City, Iowa, United States

Research Mentor(s)

JB

Jeffrey A. Banas, PhD

Director, Iowa Institute for Oral Health Research
University of Iowa College of Dentistry, Iowa City, IA
Iowa City, Iowa, United States

Program Director(s)

TM

Teresa Marshall, PhD, RDN/LDN

Professor
University of Iowa College of Dentistry and Dental Clinics
Iowa City, Iowa, United States

Purpose: The oral microbiome consists of intricate interactions between organisms that when out of balance can be a primary factor in the development of oral disease. An option for reducing the risk of oral disease is to identify probiotic strains that inhibit the growth of oral pathogens or in some way promote oral health. We hypothesize that bacterial strains isolated from children with a caries free history will be a source of probiotic candidates that inhibit the growth of cariogenic or periodontal pathogens or suppress chronic inflammation.

Methods: Antagonistic effects of candidate probiotic strains were assessed by measuring zones of inhibition when grown in close proximity to pathogenic (S. mutans, S. sobrinus, C. albicans) or health-related (S. sanguinis) oral microbes. Quantitative Polymerase Chain Reaction was used to quantify relative expression of pro- and anti-inflammatory cytokines in co-cultures of probiotic candidates and mouse macrophage RAW 264.7 cells.

Results: Two (HP3 and HP5) of ten mildly acidogenic probiotic candidates were found to possess strong antagonistic activity towards S. mutans. Four (IOWA1-4) other probiotic candidates, previously determined to inhibit S. mutans, significantly elevated expression of the anti-inflammatory cytokine IL-10 in a mouse macrophage co-culture.

Conclusion: The data from the candidates’ antagonism of S. mutans and influence on cytokine expression supports the hypothesis, but the effectiveness and limitations of each candidate strain vary suggesting that the most effective approach to promote oral health via probiotics will be a combination of strains with diverse properties.