Fungal exposome, human health, and unmet needs: A 2022 update with special focus on allergy.

Humans inhale, ingest, and touch thousands of fungi each day. The ubiquity and diversity of the fungal kingdom, reflected by its complex taxonomy, are in sharp contrast with our scarce knowledge about its distribution, pathogenic effects, and effective interventions at the environmental and individual levels. Here, we present an overview of salient features of fungi as permanent players of the human exposome and key determinants of human health, through the lens of fungal allergy and other fungal hypersensitivity reactions. Improved understanding of the fungal exposome sheds new light on the epidemiology of fungal-related hypersensitivity diseases, their immunological substratum, the currently available methods, and biomarkers for environmental and medical fungi. Unmet needs are described and potential approaches are highlighted as perspectives.

Airborne fungi spores distribution in various locations in Lagos, Nigeria.

Exposure to outside air microorganisms especially fungi has been linked with illness such as allergic respiratory symptoms, rhinitis, asthma, and infection such as mycosis. Airborne fungal composition was sampled from five locations in Lagos State, Nigeria, between May 2014 and April 2016. Fungi spores were collected using the sedimentation plate method with the Petri dishes of dichloran-glycerol 18 (DG-18) and potato dextrose agar (PDA) media. Fungi sporulated faster on DG-18 agar plate as compared with PDA. The abundances of fungal spores collected monthly at the locations varied. The most abundant spores came from the fungi were Aspergillus niger (14.47%), Aspergillus sydowii (10.37%), and Aspergillus flavus (7.93%). Additional species were present in the collections including Ascomycetes: Penicillium funiculosum (5.49%), Neurospora crassa (5.32%), Penicillium oxalicum (4.71%), Penicillium pinophilum (2.88%), Fusarium verticillioides (3.05%), Penicillium simplicissimum (1.83%), Aphaderanum sp. (0.22%), Curvularia sp. (0.22%), Aspergillus oryzae (0.22%), and Paecilomyces sp. (0.61%) and the Mucoromycotina Zygomycetes: Rhizopus oryzae (4.10%) and Mucor sp. (3.44%). Fungal concentrations were significantly higher (P ≤ 0.05) during the rainy season compared with the dry season. Aspergillus and Penicillium were the most predominant airborne fungal genera while Mucor, Alternaria, and Cladosporium were some of the least observed. Generally, abundance of fungi was significantly high during the wet season in all the studied locations.

Biomarkers of Oxidative Stress as Indicators of Fungi Environmental Pollution in Balb/c Albino Mice Monitored from South West, Nigeria.

The presence and detection of common airborne fungi in an area are important for the prevention and treatment of allergic fungal diseases. Because of the ubiquitous nature of fungi, the effect of four different fungal species in production of antioxidant and reactive oxygen species production in balb/c albino mice was investigated. Fifty-four balb/c mice were randomly divided into eight groups (n = 6) and a normal control group. Four different fungal plates, comprising Aspergillus flavus, Aspergillus penicillioides, Penicillium citrinum, and Penicillium chrysogenum, which were the most abundant fungi species sampled in the environment were cultured for one week to make 2.3 x 107 and 3.2 x 105 spores and injected intranasally in sterile saline into the nostrils of each of the mice. Results showed that all fungal inoculated organism produced statistically (P<0.05) significant reactive oxygen species while antioxidant parameters were significantly decreased in a dose dependent manner compared with normal control mice. It is therefore concluded that Aspergillus flavus, Aspergillus penicillioides, Penicillium citrinum, and Penicillium chrysogenum can alter and decrease immune function in balb/c mice. Therefore, this study was conducted to identify the most common airborne fungal species present in Southwest Nigeria and to study their allergic reactions.