Scope of Research
The Laboratory for Oral Infectious Diseases studies bacterial viruses (or bacteriophages) and their products in order to develop antimicrobial agents that are useful in the treatment of antibiotic-resistant bacterial infections.
Among the several ongoing research efforts in this lab are studies focused on the Enterococcus faecalis bacteriophage φEf11, which involve the
- creation of genetic variants useful in the treatment of E. faecalis infections.
- cloning, expression and isolation of the lytic enzymes of this virus.
- evaluation of isolated lytic enzymes for usefulness in the treatment of antibiotic-resistant enterococcal infections.
Research is also focused on the development of bacteriophage lytic enzymes effective in the treatment of antibiotic-resistant E. faecium infections and gram-negative infections.
In addition, future studies will investigate the mechanism of prophage activation by human fibroblastic cells in lysogenic strains of the periodontal pathogen Aggregatibacter actinomycetmcomitans (Aa).
Collaborations
The laboratory’s notable research partnerships include the following.
- A collaboration with the University of Rome to genetically engineer a variant of the E. faecalis bacteriophage EF1TV to have greater lytic activity than the wild type.
- A collaboration with the State University of Rio de Janeiro to learn the mechanism by which Aa lysogens are induced by human fibroblasts.
- An ongoing collaboration with the J. Craig Venter Institute for sequencing and analyzing the genomes of bacteriophages studied at the lab.
Facilities
Located on the third floor of the Kornberg School of Dentistry, the Laboratory of Oral Infectious Diseases is a micro- and molecular-biology facility encompassing 1,500 square feet. The laboratory contains the following research and equipment spaces.
- Dark room
- Equipment room
- Glassware processing and sterilization facility
- Sterile room for aseptic transfers
- Tissue culture laboratory
- Walk-in cold room
- Walk-in warm room
Several pieces of major equipment are housed in these research spaces, including the following.
- Beckman L7-65 ultracentrifuge
- CO2 incubator
- Explosion-resistant refrigerator
- Inverted phase contrast microscope
- Laminar flow hood
- Lyophilizer
- Microcentrifuge
- Spectrophotometer
- Speed evaporator
- Superspeed centrifuges with associated rotors
- Tangential flow ultrafiltration apparatus
- Vacuum oven
The laboratory was designated as a biosafety BSL-2 facility by Temple University’s Biosafety Committee.
Selected Publications
Stevens RH, Zhang H, Kajsik M, Płoski R, Rydzanicz M, Sabaka P, Šutovský S. Successful use of a phage endolysin for treatment of chronic pelvic pain syndrome/chronic bacterial prostatitis. Frontiers in Medicine 2023 August; 10: 1238147.
Stevens RH, Rams TE, Whitaker EJ. Ben Hammond: Oral Microbiologist, Renaissance Man. Journal of Dental Research 2023; 102(4): 361-363.
Fagundes Marques B, Coelho Gimarães T, Guimarães Fischer R, Monnerat Tinoco J, Ramoa Pires F, Lima da Cosa Jr J, Stevens R, Barretto Tinoco E. Morphological alterations in tongue epithelial cells infected by SARS-CoV-2: a case-control study. Oral Diseases 2022; 28(Suppl. 2): 2417-2422.
Zhang H, Stevens R. Intrinsic resistance of Enterococcus faecalis strains to fEf11 phage endolysin is associated with the presence of fEf11 prophage. Archives of Virology 2021; 166(1): 249-258.