# More Than Mechanical Retention: Characterization of Lactobacillus Clinical Strains Using In Vitro Models

> **NIH NIH R21** · LSU HEALTH SCIENCES CENTER · 2024 · $221,250

## Abstract

SUMMARY
Dental caries remains among the most prevalent infectious disease worldwide, costing USA tens of billions
of dollars annually in associated care and productivity losses. Dental caries is a result of imbalance of the
indigenous microbiota on the tooth surface known as dental plaque, and the acidic metabolites of bacterial
metabolism are directly linked to the disease development. It is well understood that conditions like
continuous consumption of fermentable sugars, especially sucrose and saliva deficiency favor the
emergency of a highly acidogenic and aciduric plaque microbiota, which include Streptococcus mutans and
lactobacilli. Lactobacillus (Lb) sp. were the first implicated in dental caries over a century ago, but major
gaps remain in knowledge concerning how the different Lb sp. establish and persist in the plaque
microbiota and promote the development of carious lesions. In this study, a collection of hundreds of
different clinical Lb isolates will be examined using well established in vitro models to elucidate how major
groups of Lb sp. colonize and establish on a surface; how S. mutans and environmental conditions may
modulate the ability of major Lb sp. to establish and compete in a mixed-species consortium; and how
interactions between S. mutans and major Lb sp. influence the community dynamics under conditions
typical of the oral cavity. It is highly anticipated that the results from this study will lead to novel insights on
each of these aspects and the roles of oral Lb in plaque microbiota and dental caries. Together, the
information derived from this study should also serve as a foundation for further investigation on the
pathophysiology of oral Lb, the plaque biofilm ecology, and the development of novel strategies against
dental caries and other conditions where dysbiotic microbiota is a major underlying factor.

## Key facts

- **NIH application ID:** 10758275
- **Project number:** 5R21DE031856-02
- **Recipient organization:** LSU HEALTH SCIENCES CENTER
- **Principal Investigator:** ZEZHANG TOM WEN
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $221,250
- **Award type:** 5
- **Project period:** 2023-01-01 → 2025-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10758275

## Citation

> US National Institutes of Health, RePORTER application 10758275, More Than Mechanical Retention: Characterization of Lactobacillus Clinical Strains Using In Vitro Models (5R21DE031856-02). Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/grant/nih/10758275. Licensed CC0.

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