[A Preliminary Study on the Effect of CD47-Targeted Immunotherapy on Oral-Gut Microbiota]

Objective

To study the effects of CD47-targted immunotherapy on the oral-gut microbiota of immune-competent mice.

Methods

A peritoneal metastatic colon cancer model was constructed in immune-competent mice. Anti-CD47 monoclonal antibody was intraperitoneally administered to the mice in the treatment group, while PBS was administered to mice in the control group. Tumor growth was documented with small animal live imaging technology. 16S rRNA sequencing technology was used to analyze the composition and diversity of oral-gut microbiota.

Results

The alpha diversity of oral microbes in the anti-CD47 monoclonal antibody treatment group decreased, and the difference was statistically significant. There was no significant change in the alpha diversity of gut microbes. Differential species analysis showed significantly decreased abundance of Staphylococcus, Jeotgalicoccus, and Sporosarcina in the oral microbiota of mice in the treatment group compared to that of mice in the control group. The abundance of Bacteroides in the gut microbiota was significantly higher in the treatment group.

Conclusion

CD47-targted immunotherapy has a rather significant impact on the diversity of oral microbiota in mice, but does not have significant impact on the species diversity of gut microbiota.

[Omicron Variant of SARS-CoV-2 and Its Potential Impact on Dental Practice]

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been raging across the world for over two years, but the daily reported numbers of new infections and deaths are still increasing. The newly identified Omicron variant has significant changes in its transmissibility and pathogenicity due to the multiple mutations in the spike protein, posing new challenges to the global public health. World Health Organization has categorized Omicron as a variant of concern (VOC). The spread of SARS-CoV-2 and its variants has caused disruptions to the dental practice worldwide. During the course of diagnosis and treatment of dental care, face-to-face communication at close quarters, droplets, aerosols, and exposure to saliva and blood increase the risks of SARS-CoV-2 transmission. The emergence of new variants, especially the Omicron variant, has formed new challenges to dental healthcare provision. In addition, oral tissues, including the tongue and oral mucosa, can overexpress the angiotensin converting enzyme 2 (ACE2), which is also the binding receptors of SARS-CoV-2. As a result, the oral cavity is one of the target sites of SARS-CoV-2 infection. SARS-CoV-2 infection in oral cavity may cause different oral complications, such as loss of taste. However, there are few reports about Omicron and the other variants of SARS-CoV-2 and their impacts on dental healthcare provision. Herein we made an overview of the Omicron variant and its characteristics, including its pathogenicity and immune evasion, and its potential impact on dental practice. We also proposed some control measures with the aim of reducing the possible transmission of SARS-CoV-2 and its variants during dental care.

[Innovative Instructional Reform and Practice of Oral Microbiology-A Course in Undergraduate Stomatology Curriculum]

Oral Microbiology is a vital component of the basic science of stomatology and an important compulsory course for undergraduate students of stomatology, focusing on the oral microbiology and microecology, the pathogenesis of oral infectious diseases, and the relationship between oral microbes and human health. Our faculty team have made reforms of the theory and laboratory teaching of the course Oral Microbiology. We have introduced in the classroom the concept of Three Comprehensive Approaches to Education-the full involvement of everyone, the through-course approach and all-round education-and offered inquiry-based instruction through a combination of extracting the core information from every chapter, using the core information as the foundation, integrating the core information with clinical problems, and using experiment operation to foster in the students an attitude of solving clinical problems through research. These teaching innovations improved the undergraduate students'motivation to learn. We evaluated the teaching effect with questionnaire surveys. The results suggested that the students showed high interest in learning and were satisfied with our teaching innovations. In addition, student performance evaluation for the course showed significant improvement, indicating that the instructional reform program of Oral Microbiology was conducive to students'understanding and mastery of the course content, improved student motivation to learn and their grades, and received positive reviews from the students. We report herein, from three aspects, the course innovations and the experiences gained. We discussed the significance of integrating ideological and political theories teaching in all courses and using innovative teaching materials and teaching models and, highlighted their importance in the education of stomatology students, and proposed suggestions to further improve the course design of Oral Microbiology.