Pathogenomic studies on dysbiosis in skin microbiome of leprosy patients undergoing drug regimen treatment from India

Background: The morphology and physiological features of various sites on the human skin define the composition of skin microbiome. Several recent studies have also described associations between compositional variations for skin microbiome and progression of dermatological disorders specifically acne, psoriasis, atopic dermatitis and vitiligo. Leprosy is one of the skin related disease linked with social stigma. It is caused by Mycobacterium leprae and Mycobacterium lepromatosis. Dysbiosis of skin microbiome and its effect on outcome of the leprosy requires detailed investigation.

Objectives: This study was conducted to explore the community structure of skin microbial communities in Indian leprosy patients undergoing drug regimen treatment and healthy individuals as controls.

Methods: Institutional ethics clearance and informed consents were considered for the study. Skin swabs from lesional and non-lesional skin sites for 29 leprosy patients and similar sites from 30 healthy individuals were collected in leprosy clinics in accordance with the study design. All the patients were diagnosed for high bacillary load of M.leprae. Microbiome DNA was isolated and sequenced for V1-V3 16S rRNA variable region using Illumina sequencers. All the sequences were de-multiplexed and subjected to Microbiome analysis using QIIME 2 tools to investigate the variability in microbiome between different study groups.

Results: A stark difference was observed between the taxonomic profiles for skin microbiota of leprosy patients and healthy individuals but insignificant results with the samples analyzed for respective leprosy lesional and adjoining non-lesional skin sites.

Discussions: Our analysis shows a decline in firmicutes related OTUs in leprosy patients in comparison to healthy individuals. Alpha diversity accessed using various diversity indices indicates a distinct depletion of Staphylococcus genera in samples from affected sites of leprosy patients. This kind of studies can assist skin microbiome restoration research that corresponds to better disease management and diagnosis.