Cytotoxicity of Aspergillus Section Fumigati Isolated from Health Care Environments

Abstract

This study analyzed 57 Aspergillus section Fumigati (AF) isolates collected by active and passive sampling (N = 450) in several health care facilities and from biological sampling of health care workers (N = 25) and controls (N = 22) in Portugal. All isolates were cultured in different media and screened for azole resistance. Cytotoxicity was assessed for 40 isolates in lung epithelial cells and kidney cells using the MTT assay. Aspergillus section Fumigati was prevalent in the health care facilities and in nasal swabs from health care workers and controls. All AF isolates reduced cell viability and presented medium to high cytotoxicity, with cytotoxicity being significantly higher in A549 lung epithelial cells. The cytotoxicity of isolates from air and nasal swab samples suggested the inhalation route as a risk factor. Notably, 42% of AF isolates exhibited a pattern of reduced susceptibility to some of the most used antifungals available for the treatment of patients infected with these fungi. In sum, the epidemiology and clinical relevance of Aspergillus section Fumigati should continue to be addressed. A deeper understanding of the mechanisms underlying Aspergillus-mediated cytotoxicity is necessary.

Electrostatic Dust Cloth: A Useful Passive Sampling Method When Assessing Exposure to Fungi Demonstrated in Studies Developed in Portugal (2018–2021)

“…EDC was applied only with one other sampling method in the studies performed in dwellings to avoid disturbance in the occupant’s routine. In fact, from the four studies performed in dwellings, two filters of 47 mm diameter quartz fiber were also used to collect particulate matter [ 17 , 23 ]. In the remaining two, in one, PM2.5 and PM2.5–10 were measured with a medium volume sampler [ 16 ], and in the other, active sampling by impaction method was also performed [ 20 ].…”

“…contamination was the FFH due to the observed buildings damage and leakages [ 21 ]. Mycotoxin’s detection [ 18 , 22 ] and cytotoxicity assessment using different cell lines [ 13 , 18 , 23 ] were also assays employed in enlarged studies dedicated to microbiologic agents.…”

“…Almost all the studies used culture-based methods and qPCR for the detection of Aspergillus sections. The exception, where only culture-based methods were applied, was in the study performed in 12 bakeries [ 10 ], the study performed in different settings where molecular identification was achieved [ 31 ], and a study concerning Aspergillus section Fumigati where the isolates were recovered by culture-based methods for further analyses [ 23 ]. In the studies where culture-based methods and qPCR detection were applied side by side, complementary results were obtained with higher detection of Aspergillus sections, mainly section Fumigati , by molecular tools.…”

“…This sampling method is appropriate for large-scale epidemiological studies intending to measure microbial exposure, and to complement exposure information collected by building inspections dedicated to spotting dampness and mold [ 3 , 4 ]. EDC is also being used to assess microbial contamination using molecular tools as stand-alone analyses [ 4 , 5 , 6 , 7 , 8 ], even the most refined ones such as sequencing [ 2 ], or using side by side, culture-dependent, and independent methods [ 3 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ]. In fact, the use of qPCR analyses from EDC is a promising tool to accurately measure microbial contamination in dwellings [ 4 , 8 , 24 ].…”

“…In fact, the use of qPCR analyses from EDC is a promising tool to accurately measure microbial contamination in dwellings [ 4 , 8 , 24 ]. Additionally, it has also been used to perform the fungal azole resistance screening in different indoor environments [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ] and to identify MRSA presence and level of contamination in specific occupational environments [ 7 ]. Further, aside from microbial contamination, this sampling method has been applied to assess microbial metabolites, such as endotoxins [ 27 , 28 , 29 ] and mycotoxins [ 18 , 22 ].…”