Systematic Genetic Interaction Analysis Identifies a Transcription Factor Circuit Required for Oropharyngeal Candidiasis

The pathology of oral candidiasis has features of biofilm formation, a well-studied process in vitro . Based on that analogy, we hypothesized that the network of transcription factors that regulates in vitro biofilm formation has similarities and differences during oral infection.

Comparison of percutaneous vs oral infection of hamsters with the hookworm Ancylostoma ceylanicum: Parasite development, pathology and primary immune response

Background Hundreds of millions of people in poor countries continue to suffer from disease caused by bloodfeeding hookworms. While mice and rats are not reliably permissive hosts for any human hookworm species, adult Golden Syrian hamsters are fully permissive for the human and animal pathogen Ancylostoma ceylanicum. Similar to humans, hamsters may be infected with A. ceylanicum third-stage larvae orally or percutaneously. Oral infection typically leads to consistent worm yields in hamsters but may not accurately reflect the clinical and immunological manifestations of human infection resulting from skin penetration. Methodology/Principal findings In this study we compared host responses following percutaneous infection to those utilizing an established oral infection protocol. Infected hamsters exhibited a dose-dependent pathology, with 1000 percutaneous larvae (L3) causing anemia and adult worm recovery comparable to that of 50 orally administered L3. A delayed arrival and maturity of worms in the intestine was observed, as was variation in measured cellular immune responses. A long-term study found that the decline in blood hemoglobin was more gradual and did not reach levels as low, with the nadir of disease coming later in percutaneously infected hamsters. Both groups exhibited moderate growth delay, an effect that was more persistent in the percutaneously infected group. Fecal egg output also peaked later and at lower levels in the percutaneously infected animals. In contrast to orally infected hamsters, antibody titers to larval antigens continued to increase throughout the course of the experiment in the percutaneous group. Conclusions/Significance These results demonstrate that the route of infection with A. ceylanicum impacts disease pathogenesis, as well as humoral and cellular immune responses in an experimental setting. These data further validate the utility of the Golden Syrian hamster as a model of both oral and percutaneous infection with human hookworms.

Propolis and Diet Rich in Polyphenols as Cariostatic Agents Reducing Accumulation of Dental Plaque

Conducted studies indicate the relationship between oral health and systemic diseases. Moreover, the latest research indicated that cariogenic bacteria may severely influence the course of SARS-CoV-2 infection and increase risk of COVID-19 complications. This article aims to review various applications of propolis and pay attention to a healthy diet rich in polyphenols, which may allow the reduction of dental plaque accumulation. A literature review has been conducted from June until November 2021. It showed that propolis could be a useful agent in decreasing the accumulation of dental plaque. Moreover, a diet rich in polyphenols prevents cariogenic bacteria and reduces the accumulation of dental plaque. A reduction of a dental plaque may influence the risk of a severe course of COVID-19. Therefore, propolis and a diet rich in polyphenols may play an important role in prophylaxis of systemic diseases. Recently, it has been proven that oral infection may affect cardiovascular system, musculoskeletal system, respiratory system, nervous system, as well as may be a risk factor for diabetes mellitus. These aspects should stimulate clinicians to further research about polyphenols.

Vaccine Strategies for Human Papillomavirus-Associated Head and Neck Cancers

The rising incidence of oropharyngeal squamous cell cancers (OPSCC) in the United States is largely attributed to HPV. Prophylactic HPV vaccines have demonstrated effectiveness against oral infection of HPV 16 and HPV 18. We review the global epidemiology and biology of HPV-related cancers as well as the development of HPV vaccines and their use worldwide. We also review the various strategies and challenges in development of therapeutic HPV vaccines.

Human Papillomavirus Oral Infection: Review of Methodological Aspects and Epidemiology

Oral infection by Human Papillomavirus (HPV) has recently gained great attention because of its involvement in the development of a subset of head and neck squamous cell carcinoma. The role of specific Alpha-HPVs in this regard has been well established, whereas the contribution of other genera is under investigation. Despite their traditional classification as “cutaneous” types, Beta and Gamma HPVs are frequently detected in oral samples. Due to the lack of a standardized protocol, a large variety of methodologies have been used for oral sample collection, DNA extraction, HPV detection and genotyping. Laboratory procedures influence the evaluation of oral HPV prevalence, which largely varies also according to the population characteristics, e.g., age, gender, sexual behavior, Human Immunodeficiency Virus (HIV) status. Nevertheless, oral infection by Beta and Gamma HPVs seems to be even more common than Alpha-HPVs. The latter is 5–7% in the general population, and increases up to 30% approximately in HIV-infected men who have sex with men. Despite major advances in the evaluation of oral HPV prevalence, its natural history is still little understood, especially for Beta and Gamma HPVs. The latest technologies, such as Next Generation Sequencing (NGS), can be exploited to gain new insights into oral HPV, and to improve the identification of novel HPV types.

γδ T Cells Differentially Regulate Bone Loss in Periodontitis Models

γδ T cells are nonclassical T lymphocytes representing the major T-cell population at epithelial barriers. In the gingiva, γδ T cells are enriched in epithelial regions adjacent to the biofilm and are considered to regulate local immunity to maintain host-biofilm homeostatic interactions. This delicate balance is often disrupted resulting in the development of periodontitis. Previous studies in mice lacking γδ T cells from birth ( Tcrd-/- mice) examined the impact of these cells on ligature-induced periodontitis. Data obtained from those studies proposed either a protective effect or no impact to γδ T cells in this setting. Here, we addressed the role of γδ T cells in periodontitis using the recently developed Tcrd-GDL mice, enabling temporal ablation of γδ T cells. Specifically, the impact of γδ T cells during periodontitis was examined in 2 modalities: the ligature model and the oral infection model in which the pathogen Porphyromonas gingivalis was administrated via successive oral gavages. Ablation of γδ T cells during ligature-induced periodontitis had no impact on innate immune cell recruitment to the ligated gingiva. In addition, the number of osteoclasts and subsequent alveolar bone loss were unaffected. However, γδ T cells play a pathologic role during P. gingivalis infection, and their absence prevented alveolar bone loss. Further analysis revealed that γδ T cells were responsible for the recruitment of neutrophils and monocytes to the gingiva following the exposure to P. gingivalis. γδ T-cell ablation also downregulated osteoclastogenesis and dysregulated long-term immune responses in the gingiva. Collectively, this study demonstrates that whereas γδ T cells are dispensable to periodontitis induced by the ligature model, they play a deleterious role in the oral infection model by facilitating pathogen-induced bone-destructive immune responses. On a broader aspect, this study highlights the complex immunopathologic mechanisms involved in periodontal bone loss.

Oral candidiasis and the risk factors: a serial case reports

Oral candidiasis (OC) is also referred as ‘thrush’ is caused by the infections of the tongue and other oral mucosal sites and characterized by fungal overgrowth and invasion of superficial tissues. The main causative agent of 95% OC cases is Candida albicans. The prevalence of fungal oral infection was increased due to the increasing use of antibiotic and immunodeficiency condition. However, many factors have been suggested as risk factors for oral colonization. These predisposing factors are divided into local and systemic factors. We present two cases of patient with oral candidiasis that have admitted at Wangaya Regional Hospital, Denpasar, Bali, Indonesia with different precipitating factors in order to remind health provider that oral candidiasis does not only occur in people living with HIV/AIDS (PLWHA).

Mucosal Bacteria Modulate Candida albicans Virulence in Oropharyngeal Candidiasis

By comparing Candida albicans virulence and the mucosal bacterial composition in a mouse oral infection model, we were able to dissect the effects of the host environment (immunosuppression), infection with C. albicans , and local modulating factors (availability of sucrose as a carbon source) on the mucosal bacterial microbiome and its role on fungal virulence. We showed that changes in endogenous microbial communities in response to sucrose can lead to attenuation of fungal disease.

Brain abscess of odontogenic origin in patients with malignant tumors: A report of two cases

Background: Oral infection and dental manipulations can lead to the development of brain abscesses, a rare but potentially life-threatening condition. Herein, we report patients undergoing cancer treatment who developed brain abscesses of odontogenic origin at our hospital. Case Description: Two patients developed brain abscesses during cancer treatment. Both underwent neurosurgical aspiration, and the causative microorganism was identified as Streptococcus intermedius of the Streptococcus anginosus group, which is a part of the normal bacterial flora in the oral cavity. There was clinical and radiographic evidence of dental infection in one of the patients diagnosed with a brain abscess of odontogenic origin. No infectious foci were found in the other patient during hospitalization for the abscess. However, the patient had undergone extraction of an infected tooth approximately 3 months before admission for the abscess, suggesting origination from an oral infection or dental manipulation. The patients’ cancers rapidly worsened because cancer treatment in both patients was interrupted for several months to treat the brain abscess. Conclusion: Oral infections can cause severe infections, such as brain abscesses, particularly during the treatment of malignant tumors. Improving the oral environment or treating oral infections before initiating treatment for malignant tumors is highly recommended. In addition, the possibility of odontogenic origin should always be considered as a potential etiology of brain abscesses.