In this EUREKA project (RFA-GM-10-009), we will accelerate the development of knowledge towards a clinical approach to thwart invasive oral pathogens associated with periodontitis and candidiasis. Oral keratinocytes appear to protect against and suppress invasive pathogens using two compartmentalized, intracellular antimicrobial effector systems: calprotectin in the cytosol and LL-37 in endosomes. By targeting these effectors, we plan to use two approaches to augment keratinocyte intracellular resistance to invasive pathogens. We hypothesize that intra-keratinocyte resistance against invasive microbial pathogens can be increased by transient delivery of specific antimicrobial effector mRNAs (e.g., S100A8 and S100A9) or specific agonists (e.g., vitamin D analogues to upregulate LL-37). Avoiding the use of transgenes, we will use the unusual approach of introducing calprotectin and/or LL-37 mRNAs into the keratinocyte. For comparison, in some experiments we will stimulate cells with vitamin D analogues to upregulate LL-37. We will learn whether endosomal and cytoplasmic resistance against invasive microbes can be selectively augmented. To learn whether the application of these specific mRNAs or vitamin A analogues to intact tissues will prove efficacious, and to consider cytotoxic, proinflammatory immune, and carcinogenic side effects, we will concurrently model this system in human tonsil explants ex vivo. Collectively, the experiments will characterize vitamin D analogues and transfer of antimicrobial effector mRNAs for the mechanism and effectiveness in augmenting intracellular innate resistance to invasive oral pathogens in oral keratinocytes. Our strategy may prove to be a valuable compliment to vaccines and antibiotics for most common oral infections, which are not life threatening and have relatively low morbidity. For these infections, vaccines have an unacceptable risk-benefit ratio. Antibiotics promote the risk of microbial resistance and host allergy. Our approach would circumvent these concerns.

Public Health Relevance

Antibiotics do not cure common oral infections such as periodontitis and candidiasis and vaccines are unavailable. The challenge is how to make the oral mucosa more resistant to invasive oral pathogens. To respond to this challenge, we will develop an alternative approach to gene therapy, which will increase production of normal antimicrobial effector molecules in oral mucosal epithelial cells.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
5R01DE021206-04
Application #
8490700
Study Section
Special Emphasis Panel (ZDE1-RW (11))
Program Officer
Rodriguez-Chavez, Isaac R
Project Start
2010-09-01
Project End
2014-05-31
Budget Start
2013-06-01
Budget End
2014-05-31
Support Year
4
Fiscal Year
2013
Total Cost
$287,021
Indirect Cost
$96,941
Name
University of Minnesota Twin Cities
Department
Dentistry
Type
Schools of Dentistry
DUNS #
555917996
City
Minneapolis
State
MN
Country
United States
Zip Code
55455
Silva, Emmanuel J; Argyris, Prokopios P; Zou, Xianqiong et al. (2014) S100A8/A9 regulates MMP-2 expression and invasion and migration by carcinoma cells. Int J Biochem Cell Biol 55:279-87
Gaffen, S L; Herzberg, M C; Taubman, M A et al. (2014) Recent advances in host defense mechanisms/therapies against oral infectious diseases and consequences for systemic disease. Adv Dent Res 26:30-7
Zou, Xianqiong; Sorenson, Brent S; Ross, Karen F et al. (2013) Augmentation of epithelial resistance to invading bacteria by using mRNA transfections. Infect Immun 81:3975-83
Bando, Mika; Zou, Xianqiong; Hiroshima, Yuka et al. (2013) Mechanism of interleukin-1* transcriptional regulation of S100A9 in a human epidermal keratinocyte cell line. Biochim Biophys Acta 1829:954-62