Gingival spatial analysis reveals geographic immunological variation in a microbiota-dependent and -independent manner

Understanding the impact of the microbiota on oral mucosal epithelial barriers, particularly within the gingiva, is essential for elucidating the mechanisms underlying oral health and disease. The gingiva exhibits intricate tissue architecture and undergoes dynamic microenvironmental shifts influenced by various factors. Notably, microbial colonization emerges as an early-life factor that plays a significant role in shaping the functional and immunological maturation of the gingival epithelium. This study utilizes spatial transcriptomic analysis to unveil distinct immunological characteristics between the buccal and palatal regions of the murine gingiva, impacting natural alveolar bone loss. Moreover, the analysis identifies a significant influence of the microbiota on the development and function of the junctional epithelium, which faces the oral microbial plaque, offering new insights into neutrophil recruitment to this strategic location. Additionally, the microbiota is found to impact fundamental functions of the gingival epithelium, including proliferation kinetics and barrier sealing. In conclusion, this study emphasizes the crucial role played by the microbiota in regulating gingival barriers and brings attention to its unique influence on specific epithelial regions within the gingiva.