Skin microbiome: What is known today?

Abstract

Human skin is the largest yet complex organ that performs many functions. The skin barrier is crucial for survival, preventing moisture loss and the entry of infectious or toxic substances. Skin is also a complex habitat for a diverse population of microbiota. During childbirth and subsequent exposure to the postnatal environment, the skin is colonized by many microbes, many of which are commensal or symbiotic. The useful functions of the resident microbiota include inhibition of pathogenic species through various mechanisms that are actively studied. Modern research is increasingly focused on the role of human microbiomes, including skin microbioms, in the development of a range of pathological diseases, including dermatological, allergic and infectious diseases. Due to the growing spread of the 16S rRNA bacteria gene sequencing method, more and more information on the microbial composition of various body systems, including the skin, is becoming available every year. The review presents current data on the composition of a healthy skin microbiome and its changes over the course of human’s life, and demonstrates some mechanisms of its effect on the health of the skin and the body as a whole. Special attention is paid to the concept of ecological niches of skin, their peculiarities and unique microbial composition. The role of microbiomal abnormalities in the development of a number of chronic inflammatory skin diseases, including atopic dermatitis, psoriasis and acne, was also analyzed.