16S rRNA Gene Sequencing Analysis of the Human Cutaneous Microbiome : workflow setup and influencing factors

Complife Italia specialises in consulting and testing services for the cosmetic, nutraceutical, and medicaldevices markets, and offers tailored, state of the art solutions. Our clients being interested in the effect oftheir products on the cutaneous microbiome, the collaboration with the University of Eastern Piedmont(UPO) started in 2019, and by summer 2020 the Complife Microbiome Laboratory was fully operational atCAAD-UPO.The human microbiome has long been recognised as a fundamental adjuvant to the human system andspurred even more interest since the 2000s and the advent of Next-Generation Sequencing technologies. Infact, they allowed to overcome the severe limitations of culture-based studies (slow-growing organisms,nutrient balance, environmental conditions...) and to observe all members of the microbiome (bacteria,fungi, viruses, mites...). While these new techniques brought greater understanding of the microbialcomposition in health and disease, it also evidenced the extreme variability of the cutaneous microbiotastructure depending on the subject, its environment, and the body site.To satisfy our clients, we first established a reliable, reproducible, and repeatable workflow based on the16S rDNA sequencing approach, a method giving a broad understanding of the bacterial component of thecutaneous microbiota. We also tested variations of the pipeline to have more flexibility in our protocols andcosts. Then, we repurposed about 1000 of the 3000 samples collected through commercial studies andanalysed microbiome variations based on various factors (sex, age, season, geography) and body sites (face,armpit, chest, legs).Long-term, the Complife Microbiome Laboratory should be able to offer similar analyses on the fungalmembers of the cutaneous microbiota (focusing on the ITS-1 gene), but also to better characterise thecutaneous microbiota of the central northern Italy inhabitants by targeting bacteria and fungi of interestalso at the species level. Finally, we make our mission to use our resources to study the impact of differentfactors on the microbial communities’ composition.