The long-term goal of this project is to determine if Parotid Secretory Protein (PSP;SPLUNC2) is a dual function host-defense protein in the oral cavity. PSP is expressed in salivary glands, oral epithelial cells and saliva but its function is unknown. Expression of PSP is up-regulated by bacteria and TNF and an in silico structural analysis of PSP revealed that it may be similar to bactericidal/permeability increasing protein (BPI) and LPS-binding protein (LBP). Guided by the location of active domains in these two proteins, several PSP peptides were designed and found to exhibit both antibacterial and anti-endotoxin activities in vitro and in vivo. Based on these initial results with PSP peptides and additional preliminary data for intact PSP it is hypothesized that the dual- function antibacterial and anti-inflammatory activities detected for PSP peptides are reflected in the biological activity of the intact PSP protein.
Two specific aims will test the proposed functions of PSP.
Aim 1 will characterize the antibacterial activity of PSP. PSP peptides and recombinant PSP will be used in biochemical, cell biological and in vivo experiments to determine if PSP exhibits bacteriostatic or bactericidal activity, bacterial agglutination, and inhibition of biofilm formation.
Aim 2 will characterize the anti- inflammatory activity of PSP. PSP peptides and recombinant PSP will be used in biochemical, cell biological and in vivo experiments to determine if PSP binds LPS, blocks the action of LPS in vitro and protects mice in an LPS-induced sepsis model. If confirmed, the proposed functions of PSP will expand the group of antimicrobial host- defense proteins that are expressed in the oral cavity and participate in the defense of the oral mucosa. Thus, the research proposed here will lay the foundation for future translational research aimed at novel clinical approaches to combat infection and control inflammation.

Public Health Relevance

The goal of this proposal is to identify the biological functions of the salivary protein Parotid Secretory Protein (PSP). Preliminary data suggest that PSP plays a role in host-defense against oral and airway bacteria. Peptides based on the PSP sequence may have clinical utility as antibacterial or anti-inflammatory components.

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
5R01DE017989-04
Application #
8468676
Study Section
Oral, Dental and Craniofacial Sciences Study Section (ODCS)
Program Officer
Burgoon, Penny W
Project Start
2010-06-22
Project End
2014-05-31
Budget Start
2013-06-01
Budget End
2014-05-31
Support Year
4
Fiscal Year
2013
Total Cost
$334,255
Indirect Cost
$92,094
Name
University of Minnesota Twin Cities
Department
Dentistry
Type
Schools of Dentistry
DUNS #
555917996
City
Minneapolis
State
MN
Country
United States
Zip Code
55455
Chen, Xi; Hirt, Helmut; Li, Yuping et al. (2014) Antimicrobial GL13K peptide coatings killed and ruptured the wall of Streptococcus gordonii and prevented formation and growth of biofilms. PLoS One 9:e111579
Hirt, Helmut; Gorr, Sven-Ulrik (2013) Antimicrobial peptide GL13K is effective in reducing biofilms of Pseudomonas aeruginosa. Antimicrob Agents Chemother 57:4903-10
Holmberg, Kyle V; Abdolhosseini, Mahsa; Li, Yuping et al. (2013) Bio-inspired stable antimicrobial peptide coatings for dental applications. Acta Biomater 9:8224-31
Abdolhosseini, Mahsa; Nandula, Seshagiri R; Song, Jonathan et al. (2012) Lysine substitutions convert a bacterial-agglutinating peptide into a bactericidal peptide that retains anti-lipopolysaccharide activity and low hemolytic activity. Peptides 35:231-8
Abdolhosseini, Mahsa; Sotsky, Julie B; Shelar, Anuradha P et al. (2012) Human parotid secretory protein is a lipopolysaccharide-binding protein: identification of an anti-inflammatory peptide domain. Mol Cell Biochem 359:1-8
Gorr, Sven-Ulrik (2012) Antimicrobial peptides in periodontal innate defense. Front Oral Biol 15:84-98
Gorr, Sven-Ulrik; Abdolhosseini, Mahsa (2011) Antimicrobial peptides and periodontal disease. J Clin Periodontol 38 Suppl 11:126-41
Gorr, Sven-Ulrik; Abdolhosseini, Mahsa; Shelar, Anuradha et al. (2011) Dual host-defence functions of SPLUNC2/PSP and synthetic peptides derived from the protein. Biochem Soc Trans 39:1028-32