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. One SPF sample pooled from four SPF mice was compared with one GF sample pooled from four GF mice解析微生物群（microbiota）对口腔黏膜上皮屏障的影响，尤其是针对牙龈（gingiva）组织中的作用，对于阐明口腔健康与疾病的潜在发病机制至关重要。牙龈具有复杂精细的组织结构，且会受多种因素影响而发生动态的微环境改变。值得关注的是，微生物定植是生命早期的关键影响因素之一，可显著调控牙龈上皮的功能成熟与免疫发育过程。本研究采用空间转录组学分析，揭示了小鼠牙龈（murine gingiva）颊侧与腭侧区域间存在的独特免疫特征，该特征可影响自然状态下的牙槽骨丢失进程。此外，本分析证实微生物群对暴露于口腔菌斑的结合上皮（junctional epithelium）的发育与功能具有显著调控作用，为中性粒细胞募集（neutrophil recruitment）至这一关键位点提供了全新的研究视角。同时，研究发现微生物群可影响牙龈上皮的核心生理功能，包括增殖动力学（proliferation kinetics）与屏障封闭功能。综上，本研究强调了微生物群在调控牙龈屏障中发挥的关键作用，并关注了其对牙龈内特定上皮区域的独特调控效应。本实验将1份由4只无特定病原体（Specific Pathogen Free, SPF）小鼠组织混合制备的样本，与1份由4只无菌（Germ Free, GF）小鼠组织混合制备的样本进行了对照分析。