A novel vaccine targeting Fusobacterium nucleatum against abscesses and halitosis

Abstract

An abscess in a gum pocket, resulting from bacterial infection, is a common source of chronic halitosis. Although antibiotics are generally prescribed for abscesses, they require multiple treatments with risks of creating resistant bacterial strains. Here we develop a novel vaccine using ultraviolet-inactivated Fusobacterium nucleatum (F. nucleatum), a representative oral bacterium for halitosis. A gum pocket model, established by continuous inoculation of F. nucleatum, was employed to validate the vaccine potency. Mice immunized with inactivated F. nucleatum effectively minimized the progression of abscesses, measured by swollen tissues of gum pockets. Most notably, the immunized mice were capable of eliciting neutralizing antibodies against the production of volatile sulfur compounds of F. nucleatum. The novel vaccine inducing protective immunity provides an alternative option to conventional antibiotic treatments for chronic halitosis associated with abscesses.

Association of Fusobacterium Isolation From Periodontal Pockets With Halitosis and the Related Risk Factors in Shiraz, Iran

“…In addition, it is often associated with periodontal diseases (14). Fusobacterium species with the ability to cause oral malodor belong to endogenous flora (7). Of the total Fusobacterium isolates in our study, 23.1% were those of F. necrophorum, a proportion close to that in the study by Gomes et al (15).…”

“…The majority of isolates (82.3%, 14/17) in our study were those of F. nucleatum. F. nucleatum causes halitosis through the production of large amounts of VSCs and the accumulation of other VCS-producing bacteria (7,14). In addition, it is often associated with periodontal diseases (14).…”

“…This anaerobic microenvironment houses different bacterial species that majorly include a range of gram-negative proteolytic strains (1,3). VSC is the main product of proteolysis by these organisms, which utilizes sulfur-containing amino acid resources such as cysteine and methionine (7).…”

“…Several anaerobic gram-negative bacteria have been mentioned for their role in VSC production, with Fusobacterium species being one of the most common (5,7,8). Previously, it was shown that the plaque biofilm is a major source of halitosis-inducing VSCs produced by anaerobic gram-negative bacteria.…”

“…Previously, it was shown that the plaque biofilm is a major source of halitosis-inducing VSCs produced by anaerobic gram-negative bacteria. Fusobacterium species play a critical role in this phenomenon, along with other bacteria in plaque biofilms (7). With regard to this issue, it was previously indicated that FomA, which is one of the major outer membrane proteins of Fusobacterium nucleatum, could be an agent for recruiting other anaerobic gram-negative bacteria into periodontal pockets, thus facilitating the formation of plaque biofilms (7).…”