Shotgun Metagenomics of Biofilm Microbiome in Oral Lichen Planus With Desquamative Gingivitis.

INTRODUCTION

Oral lichen planus (OLP) is a chronic inflammatory condition often associated with desquamative gingivitis (DG). The oral microbiome's role in OLP and DG (OLP-DG) is gaining recognition, but prior 16S rRNA studies lacked taxonomic resolution. This study introduced shotgun metagenomic sequencing to thoroughly compare the supragingival and subgingival plaque microbiomes of individuals with and without OLP-DG.

METHODS

Twenty-seven participants (9 OLP-DG, 18 non-OLP) were recruited. Supra- and subgingival plaque samples were collected separately. Genomic DNA was analyzed using shotgun metagenomic sequencing. Microbial abundance and diversity were assessed through bioinformatic and statistical analyses.

RESULTS

We observed significant changes in the supragingival and subgingival microbiomes in OLP-DG. Supragingival plaque showed reduced Corynebacteriaceae and Porphyromonadaceae, with enrichment of an unnamed Synergistaceae genus and three unnamed species (Candidatus Saccharibacteria bacterium oral taxon 955 and 488 and GGB10852_SGB17523). Subgingival plaque revealed increased Flavobacteriaceae and Rhodocyclaceae, and reduced Actinomycetaceae. Although alpha or beta diversity was not significantly different, common commensals like Corynebacterium matruchotii and Streptococcus mitis were less abundant in OLP-DG patients.

CONCLUSION

This first-time application of metagenomic sequencing revealed a distinct microbiome in OLP-DG, characterized by novel bacterial species and reduced commensals, suggesting a potential role in OLP-DG pathogenesis, and warranting further study.