Analysis of the skin mycobiome in adult patients with atopic dermatitis

Abstract

With the recent availability of culture-independent sequencing methods, studies have been conducted to analyse skin micro-organisms present in patients with atopic dermatitis (AD). However, the database on the skin fungal communities, "mycobiome," has been relatively restrictive compared with the bacterial world. We aimed to comparatively analyse the overall skin mycobiome between patients with AD and healthy individuals in the Korean population. We analysed skin swab samples obtained from the antecubital fossae of 8 patients with AD and 8 healthy controls. Using sequencing method followed by direct DNA extraction and molecular PCR, taxonomic compositions of fungi at stepwise level ranks were analysed. The phylogenic marker used was internal transcribed spacer 2 regions of DNA. We observed the tendency of higher intra- and interpersonal taxonomic diversity at genus and species levels in AD samples. Non-Malassezia fungal diversity was also noticeable in the patient group compared with healthy controls. Malassezia globosa and Malassezia restricta were prevalent in all samples across both study groups, and some Malassezia species, including Malassezia sloofiae and Malassezia dermatis, characterized AD. Our data might provide a new insight into the mycobiome of adult AD, which contributes to building a systemic mycobiome database in AD.

Initial Evidence of Distinguishable Bacterial and Fungal Dysbiosis in the Skin of Patients with Atopic Dermatitis or Netherton Syndrome

“…S11 and showed disease-specific interspecies competition. Altogether, these results show a greater fungal diversity in AD than in CTRL (Han SH et al, 2018;Jagielski T et al, 2014;Zhang E et al, 2011), IV and NS. Moreover, they highlight clearest alterations in skin fungal composition in NS.…”

“…In FLG deficient epidermis, regardless of the presence of AD, a low frequency of proteolytic Gram-positive anaerobic cocci together with underrepresentation of bacterial taxa that utilize histidine as a substrate has been observed (Zeeuwen P et al, 2017). Previous work has shown trends to increased alpha-and beta-diversities of fungi at the genus and species levels in AD (Han SH et al, 2018;Jagielski T et al, 2014;Zhang E et al, 2011). Although individuals with IV are prone to develop skin fungal infection, very little is known about the composition of their fungal microbiota (Agostini G et al, 1992;Hoetzenecker W et al, 2007).…”

Contribution of Malassezia spp. to the development of atopic dermatitis

“…The genetic and environmental factors, defects of the epidermal barrier are taken into account, but the role of microorganisms and their impact on the immunology of the disease are increasingly discussed . It has been uncertain over almost two decades if opportunistic Malassezia yeast, previously known as Pityrosporum, contributes to the development of symptoms and exacerbations of atopic dermatitis . Currently, several reports have revealed the presence of specific IgE in the plasma as well as positive patch tests or reactions to Malassezia allergens in patients with AD .…”

“…Recombination techniques allowed production of six of them and their use in diagnostic tests. A high genetic diversity discovered in the Malassezia genus that has been seen especially in patients with AD prompted scientists to rebuild the taxonomy and define several new species . At least seven of currently accepted species has been regularly isolated from human skin; however, their pathogenic properties have not been fully understood.…”

Shotgun Metagenomic analysis of cutaneous microbiome in patients with atopic dermatitis

“…In this study, M. dermatis and M. sympodalis were detected with enriched abundances in adult and child respectively which could be contributed to species switching in pathogenesis of AD (Han et al, 2018). The current study provides new insight about microbiota associated to AD in Egyptian patients using shotgun metagenomic approach.…”