Figure 2.

Microbial composition of gut and skin. Skin, the largest organ of the human body, shelters numerous commensal microbes (bacteria, fungi and viruses) and prevents entry by foreign pathogens by acting as a physical barrier. Skin can be broadly categorized as sebaceous or oily (glabella), moist (antecubital fossa) or dry (volar forearm), according to the physiological characteristics of each skin site. Specific microbial groups dominate different skin sites. Like skin, human gut is a home to innumerable amounts of microbes. A number of gut bacteria (e.g, Lactobacilli, E. coli, Bifidobacterium, Streptococcus thermophilus) contribute to maintenance of human health state, whereas others (e.g., Clostridium difficile, Campylobacter, Enterococcus faecalis, Helicobacter pylori) are more prevalent in disease states. The illustration was adapted from “Immune Organs in the Human Body”, by BioRender.com (2022). Retrieved from https://app.biorender.com/biorender-templates, associated information based on .^25–27,28