bluuebunny/crossref_metadata_2025_split huggingface dataset:
S5.3d How mitochondrial complex I proteins in Candida albicans moderate phagocytosis and the production of pro-inflammatory cytokines in murine macrophages and dendritic cells
Authors: She Xiaodong , Zhang Pengyi , Calderone Richard , Liu Weida , Li Dongmei 
Published: September 2022

Abstract

S5.3 Cellular pleomorphism and fungal virulence, September 22, 2022, 3:00 PM - 4:30 PM

Objectives
Inhibition of respiration in Candida albicans impairs its colonization in the host tissues and causes avirulence in a murine vascular candidiasis model. Accordingly, blockage of the mitochondrial electron transport chain (ETC) of C. albicans by respiratory inhibitors promotes phagocytosis by increasing exposure of glucan which could be due to the mannan reduction. In our model, we have reported that 85% mannan reduction in goa1Δ, a deletion mutant of an ETC Complex I (CI) regulator, oppositely decreased phagocytosis. To understand such a difference, we broaden our investigation with three CI respiratory subunit mutants, which are either fungal-specific (nuo1Δ and nuo2Δ) or broadly conserved subunits (ndh51Δ) for cell wall analysis and innate immune responses.

Methods
We characterized mutant cell wall defects in these mutants, then analyzed their respective survival in macrophages. Fungal internalization into macrophages was visualized under fluorescent microscopy and live-cell imaging and analyzed through flow cytometry analysis. Cytokine production in dendritic cells (DCs) infected by fungal cells was measured by xMAP technology and the transcriptional profiles of murine macrophages-infected by different mutants were compared.

Results
We find that phosphopeptidomannan (PPM) reduction in goa1Δ and nuo1Δ and phospholipomannan (PLM) reduction in nuo2Δ correlate with massive inhibition of cytokine. PPM loss in nuo1Δ or goa1Δ fails to promote phagocytosis but promotes opsonized neutrophil killing. The cause of PPM insufficiency results from reduced phosphorylation of the Cek1 MAPK in goa1Δ and nuo1Δ. In contrast other three mutants, phagocytosis and cytokine production of ndh51Δ more resemble WT cells, which have shown an ∼ 30% glucan reduction due to a defective Mek1 MAPK response. The divergent immune responses to these CI mutants are shown at the transcriptional level in infected macrophages. We noted that those well-characterized host receptors such as dectins and TLR2/4 for PPM, PLM, and glucan ligands are not significantly affected at 1 h post-infection. However, the scavenger receptor CD36, integrin ICAM, and growth factor receptors are downregulated along with a generally downregulated endocytosis and antigen processing/presentation. In addition, the host metabolic processes, oxidative stress-induced senescence, apoptosis, and signaling pathways such as Ras1/Erk5, the cAMP/CREB, and TLR9 pathway, are each individually affected in the host cells.

Conclusion
We speculate that mitochondrial signals of fungal origin may also be sensed by the host immune cells to coordinate the immune responses together with cell replication and metabolism during the early stage of infection.
S5.4a Cutaneous manifestations of deep fungal infections: Aretrospective study from one tertiary hospital
Authors: Chen Peiran , Zhou Xin , Liu Wentao , Wu Angela , Feng Peiying 
Published: September 2022

Abstract

S5.4 Free oral paper session, September 22, 2022, 3:00 PM - 4:30 PM

Objectives
Analysis of the cutaneous manifestations in patients with deep fungal infections to provide a basis for clinical differentiation and diagnosis.

Method
Patients who presented to our hospital from 2016 to 2021, were definitively diagnosed with deep fungal infections by histopathology and mycological detection. Isolates of focal infections were cultured in vitro on SDA or MEA media for 14 days and the species were identified by morphological or molecular analysis. Relevant clinical data on epidemiologic, skin manifestations, underlying disease, causative fungal agent, treatment, and outcomes are collected and analyzed.

Results
A total of 15 patients were diagnosed with deep fungal infections. The respiratory system (7/15) was the most easily involved primary focus of deep fungal infection, digestive system (3/15), and nervous system (2/15) were less common. The mean age of the patients was 50.30 years. Of these, 8 were males. More than half of the cases (7/15) were presented in immunosuppressed patients, including long-term glucocorticoid use, organ transplantation, tuberculosis infection, and malignancy. Skin manifestations were varied, with plaques (5/15) being the most common type of lesion, and then papules (4/15), nodules (2/15), patches (2/15), and ulcers (2/15). Candida spp. (9/15) was the most common pathogens, followed by Talaromyces marneffei (2/15) (Fig. 1a), Cryptococcus spp. (2/15) (Fig. 1b), and Aspergillus spp. (2/15). One case had co-infection with C. albicans and Aspergillus spp.

Conclusions
Patients with deep fungal infections are often accompanied by skin manifestations, which vary between patients with deep fungal infections caused by different pathogenic fungi.
S5.4d Agrochemicals potentiate multidrug resistance and alter virulence in Cryptococcus neoformans via hitch-hiking effect of aneuploidy
Authors: Sun Liuliu , Cao Yong-bing , Yan Tian-hua , Jiang Yuan-ying , Yang Feng 
Published: September 2022

Abstract

S5.4 Free oral paper session, September 22, 2022, 3:00 PM - 4:30 PM

Objectives
Cryptococcus neoformans is an environmental fungal pathogen causing fatal pulmonary and disseminated infections in humans, especially in AIDS patients. However, only three antifungal drugs are available for the treatment of cryptococcosis: fluconazole, amphotericin B, and flucytosine. C. neoformans is worldwide distributed in nature, but environmental factors influencing antifungal drug susceptibility are largely unknown.

Methods
We tested the antifungal effect of agrochemicals against C. neoformans lab strain H99. We obtained drug-resistant adaptors. We sequenced the adaptors and got a list of adaptors bearing unique aneuploidy. We asked if aneuploidy caused multidrug resistance to antifungal drugs and if aneuploidy altered virulence in vitro and in vivo. We also investigated the molecular mechanism of aneuploidy-mediated multidrug resistance.

Results
Here we found tebuconazole and benomyl, belonging to two distinct classes of agrochemicals, could inhibit the growth of H99. However, H99 could gain resistance to both drugs mainly via aneuploidy. Importantly, particular aneuploidy also caused multidrug resistance to fluconazole, amphotericin B, and flucytosine. Furthermore, aneuploidy also altered virulence in vitro and in vivo. We found copy number variation of genes on the aneuploid chromosome caused a proportional increase in transcript and protein levels.

Conclusion
Therefore, we posit agrochemicals could enhance multidrug resistance and alter the virulence of C. neoformans via the hitch-hiking effect of aneuploidy.
S6.1d First case report of pediatric blood stream infection by Candida magnoliae in a known case of B cell ALL post -induction chemotherapy in Central India
Authors: Bhadra Subhasish , Tadepalli Karuna , Chaudhary Narendra Kumar , Bhadade Arati 
Published: September 2022

Abstract

S6.1 Antifungal Prophylaxis in Children with Cancer and HSCT, September 22, 2022, 4:45 PM - 6:15 PM

Objectives
Documentation and dissemination of findings of a rare fungal isolate in an immunosuppressed child.

Methods
A case study with rare fungal isolate in correlation to age, clinical condition, sample, and comorbidity was done. A 6-year-old male child was admitted for routine management of B cell acute lymphoid leukemia. The patient completed induction chemotherapy in July 2021. The patient was planned for consolidation in the last week of July and to rule out any infection blood and urine samples were sent. Paired blood samples were received in pediatric automated BacT/Alert blood culture bottles. After 8 days both the blood culture bottles flashed positive. On gram stain, budding yeast cells oval to globose were seen. No pseudohyphae were seen. Nigrosin staining result was negative. It was processed further on HiCrome™ agar showing cream-colored colonies at 370 C, cornmeal agar with 1% tween 80 for Dalmau technique showed only oval to globose yeast cells with blastoconidia, enlarged cells appearing as chlamydoconidia without pseudohyphae or true hyphae were seen. Glucose and sucrose were fermented and trehalose was weakly fermented. Urease was negative. Isolate was identified as Candida glabrata/Candida auris. Antifungal susceptibility showed elevated MIC for fluconazole but susceptible to amphotericin B, voriconazole, and caspofungin. As part of routine collaboration with reference center PGIMER, bloodstream Candida isolates were sent for confirmation, and quality control.

Results
The isolate phenotypically suspected as C. glabrata causing fungemia was confirmed by the reference center as C. magnoliae. Currently, patient is on routine follow-up and doing well. On reviewing of available literature on C. magnoliae; bloodstream infections in two low birth weight neonates from Brazil, one immunocompetent child with tenosynovitis from the USA, and a terminal oncology patient from Italy were noted.
In a Chinese study of 2007, phylogenetic analysis showed a close relationship of C. magnoliae to Candida krusei.

Conclusion
Immunosuppression with longstanding or repeated hospital admissions is a risk for nosocomial fungal infections, especially, bloodstream infections. Already confusing phenotypic identification among C. glabrata, C. auris, C. haemoulonii, and now the current isolate C. magnoliae further complicates and challenges diagnostic workflow impacting timely management of cases. Further studies and more documentation of such findings in literature are necessary for newer insights.
S6.3d Candida albicans commensalism in the oral mucosa is favored by limited virulence and metabolic adaptation
Authors: Gut-Landmann Salomé Leibund 
Published: September 2022

Abstract

S6.3 Fungal adaptation and evolution, September 22, 2022, 4:45 PM - 6:15 PM

Objectives
As part of the human microbiota, the fungus Candida albicans colonizes the oral cavity and other mucosal surfaces. Commensalism is tightly controlled by complex fungus-host interactions that preclude fungal elimination but also fungal overgrowth and invasion that would result in disease. As such, defects in antifungal T cell immunity render individuals susceptible to oral thrush due to interrupted immunosurveillance. The factors that promote commensalism and ensure persistence of C. albicans in a fully immunocompetent host remain less clear. In this study, we aimed at identifying determinants of C. albicans commensalism in the oral cavity.

Methods
We used an experimental model of C. albicans oral colonization in mice, profiled the transcriptome of the fungus in the mucosal tissue, and conducted functional studies with the prototypical commensal isolate 101 in host-free and host-involving conditions.

Results
C. albicans commensalism is associated with a characteristic metabolic profile tailored to the nutrient-poor conditions in the stratum corneum of the epithelium where the fungus resides. Metabolic adaptation of the commensal isolate 101 was also reflected in enhanced nutrient acquisition when grown on oral mucosa substrates. Persistent colonization of the oral mucosa by C. albicans also correlated inversely with the capacity of the fungus to induce epithelial cell damage and to elicit an inflammatory response. These immune evasive properties of isolate 101 are explained by a strong attenuation of numerous virulence genes, including those linked to filamentation. De-repression of the hyphal program by deletion or conditional repression of the transcriptional repressor NRG1 abolished the commensal behavior of isolate 101.

Conclusions
This study establishes a central role of NRG1 in the commensal lifestyle of C. albicans in the oral niche of the host.
S8.1b Is a search and destroy strategy still feasible for Candida auris in South Africa?
Authors: Govender Nelesh 
Published: September 2022

Abstract

S8.1 Tackling Candida auris in resource-limited settings, September 23, 2022, 3:00 PM - 4:30 PM

Candida auris was prospectively detected as a healthcare-associated pathogen in South Africa in 2014. However, a retrospective review of a culture collection from national laboratory-based surveillance for Candidaemia in 2009-10 showed that earlier cases had been missed owing to species misidentification. National surveillance, which was repeated during 2016-17, revealed that C. auris caused &gt;10% of cases of Candidaemia in South Africa, with most (86%) cases detected in the Gauteng Province. We recommended all hospitals to passively monitor cases of C. auris disease and colonization by each maintaining a line list of culture-confirmed cases. Facilities were thus classified into three tiers. Tier 1 (‘green status’) included facilities with no prior known cases. Such facilities were requested to report their first cases for urgent intervention. This included active colonization surveys, isolation and/or cohorts of infected or colonized patients as well as intensified infection prevention and control and antifungal stewardship activities. Tier 2 (‘orange status’) included facilities with sporadic cases defined arbitrarily as fewer than 12 cases in the past 6 months and/or fewer than three units affected. Such facilities were requested to report any increase in the number of cases compared with a baseline, clinical units affected for the first time, or apparent case clustering within the facility for investigation. Tier 3 (‘red status’) included facilities with a relative endemicity defined as &gt;12 cases and/or &gt;3 units with cases in the last 6 months. Tier 3 facilities were only requested to report increases over a baseline or apparent clustering within the facility. Owing to limited resources, colonization screening of newly-admitted patients was not recommended in acute-care facilities in South Africa. During 2019-21, the proportion attributable to C. auris increased even further to 25% (of 12 959 national cases of Candidaemia), with a concomitant reduction in cases caused by C. parapsilosis. This suggested a concerning replacement of multidrug-resistant C. auris in an ecological healthcare niche previously occupied by azole-resistant C. parapsilosis. An epidemiological shift was also observed with an expanding number of acute healthcare facilities outside Gauteng Province reporting C. auris and large persistent healthcare-associated infection outbreaks in neonatal units, particularly in the under-resourced public health sector.
S8.4b Population biology of hedgehog fungus Trichophyton e r inacei
Authors: Hubka Vit 
Published: September 2022

Abstract

S8.4 Cases of animal mycoses, September 23, 2022, 3:00 PM - 4:30 PM

Trichophyton erinacei is a main cause of dermatophytosis in hedgehogs and is increasingly reported from human infections worldwide. It is found in wild European hedgehogs (Erinaceus europaeus) but also in the African four-toed hedgehog (Atelerix albiventris), a popular pet animal worldwide. Little is known about the taxonomy and population genetics of this pathogen despite its increasing importance in clinical practice. Notably, whether there are different populations or even cryptic species associated with different hosts or geographic regions is not known. To answer these questions, we collected 161 isolates, performed phylogenetic and population-genetic analyses, determined mating type, and characterized morphology and physiology. Multigene phylogeny and microsatellite analysis supported T. erinacei as a monophyletic species, in contrast to highly incongruent single-gene phylogenies. Two main subpopulations, one specific mainly to Atelerix and the second to Erinaceus hosts, were identified inside T. erinacei, and slight differences in the size of microconidia and antifungal susceptibilities were observed among them. Although the process of speciation into two lineages is ongoing in T. erinacei, there is still gene flow between these populations. Thus, we present T. erinacei as a single species, with notable intraspecies variability in genotype and phenotype. The data from wild hedgehogs indicated that sexual reproduction in T. erinacei and de novo infection of hedgehogs from soil are probably rare events and that clonal horizontal spread strongly dominates. The molecular typing approach used in this study represents a suitable tool for further epidemiological surveillance of this emerging pathogen in both animals and humans. The results of this study also highlighted the need to use a multigene phylogeny ideally in combination with other independent molecular markers to understand the species boundaries of dermatophytes.
S9.3d Antivirulence drug discovery to disarm Candida albicans with metabolites from myxobacteria.
Authors: Vij Raghav , Tröger Sophie , Walt Christine , Haeckl F.P. Jake , Müller Rolf , Kniemeyer Olaf , Brakhage Axel , Hube Bernhard , Brunke Sascha 
Published: September 2022

Abstract

S9.3 Drug resistance in emerging pathogenic fungi, September 23, 2022, 4:45 PM - 6:15 PM
Candida albicans is an opportunistic fungal pathogen. While nearly 40%-60% of humans are colonized harmlessly by C. albicans, prolonged use of antibiotics or an immune-compromised status can lead to mucosal or deadly systemic candidiasis (Kumamoto et al., 2020). There are only three classes of antifungals available to physicians to treat and prevent severe Candidiasis. These drugs, which include polyenes, echinocandins, and azoles, protect the host by killing or inhibiting growth of C. albicans, thereby exerting a strong selective pressure toward drug resistance.

Antivirulence drugs, by contrast, target virulence traits of pathogens without affecting their growth, making drug resistance less likely to evolve. We seek to discover novel antivirulence compounds against C. albicans that keep it at, or return it to, its baseline commensal state even under conditions that support pathogenicity.

Bacteria have evolved a large repository of metabolites that can inhibit and modulate the behavior of other organisms in their environment. Clades like the predatory myxobacteria are untapped for potential antifungal and antivirulence drug discovery (Vij et al., 2021). We here screened ≈ 2800 crude extracts from myxobacteria in an in situ C. albicans-mammalian epithelial cell infection model. Typically, when oral epithelial cells (TR146) are infected by C. albicans, the fungus proliferates, forms hyphae, and invades and damages the monolayer. In our assay, we estimate the damage to epithelial cells by released lactate dehydrogenase. We also note changes to the growth and morphology of the fungus. Based on these readouts we assign antivirulence and antifungal ranks to each extract, and confirm top-ranked hits with an independent propidium iodide-based assay for host cell damage, and a colorimetric assay of fungal metabolic activity. We found that several of the top-ranked antifungal extracts also showed effects on a multi-drug resistant strain of C. auris.

Using an established pipeline, we identified several of the antifungal and antivirulent bioactive components in these extracts. After scaling the production of promising lead compounds, we will test their drugability on clinical Candida spp. strains, and identify their mode of action using large-scale Candida spp. knock-out libraries and multi-omics approaches.

Our tested extracts are likely to contain new classes of non-toxic antifungals that can potentially treat infections by multi-drug resistant fungi. We identified and confirmed several myxobacteria extracts that protected mammalian epithelial cells without severely affecting the fungus’ growth, which are, therefore, considered antivirulent.

Sources
S9.4e Molecular epidemiology of Microsporum canis infection in Japan
Authors: Mochizuki Takashi , Futatsuya Taketoshi , Anzawa Kazushi , Yamada Shigeo , Shimizu Akira 
Published: September 2022

Abstract

S9.4 Free oral presentations (late breaking), September 23, 2022, 4:45 PM - 6:15 PM

Objectives
From a series of epidemiological surveys by the Japanese Society for Medical Mycology, it is estimated that the number of Microsporum canis (M. canis) infections in Japan has increased in recent years. The purpose of this study was to observe this trend by multilocus microsatellite (MLMT) analysis, a sensitive molecular marker.

Methods
DNA was extracted from 103 strains of M. canis isolated between 2017 and 2022 from Japanese patients and pet animals. Using the DNA, PCR targeting six individual microsatellites was performed. The size of each of these amplicons was measured by capillary electrophoresis, and their genotypes were determined from the combinations of their sizes.

Results
A total of 27 genotypes were detected among the 103 strains. Among the 27, 15 had been reported in studies of strains isolated before 2017, whereas 12 were newly determined in the present study. The genotype most frequently detected in the present study was genotype A, being present in 28 of the 103 strains. By geographical region, genotype A was found in strains distributed over a wide area of Japan. Genotype A strains have been isolated from cats purchased at pet shops and/or owners of these pet animals. The highest incidence of genotype in a study of strains isolated in 2010-2014 was also genotype A. Therefore, a large number of M. canis infections originating from pet shops and animal breeders are likely prevalent in Japan today. Furthermore, a relatively large number of strains were identified as genotypes rare or absent in 2010-2014.

Conclusions
The increase in the number of M. canis infections in recent years may be the increase in infections of different genotypes, in addition to the base of constant infections by genotype A, by the present MLMT analysis.
S9.5c Malassezia-host interactions and the Il-23/17 axis
Authors: LeibundGut-Landmann Salomé 
Published: September 2022

Abstract

S9.5 Malassezia: pathogenesis and disease, September 23, 2022, 4:45 PM - 6:15 PM

The mycobiome of the skin is dominated by a single fungal genus, Malassezia. While Malassezia normally exists as a commensal without inflicting disease, the fungus has also been associated with numerous skin disorders ranging from mild conditions such as dandruff or pityriasis versicolor to severe chronic pathologies such as seborrheic or atopic dermatitis. Maintaining stable colonization and preventing pathogenicity of Malassezia is key for skin homeostasis. Our understanding of the fungal factors and host mechanisms that, through mutual interactions, promote Malassezia commensalism in healthy skin remains incomplete. From studies in humans and mice, we learned that homeostatic immunity against Malassezia is characterized by IL-17-producing T cells, including Th17 and γδT17 cells. Recent endeavors start to unravel the cellular and molecular pathways responsible for driving the protective antifungal response in the skin. While Malassezia-responsive T cells are non-inflammatory and host-beneficial, they can bear pathogenic potential and thereby be involved in the pathogenesis of inflammatory and allergic skin conditions, as preclinical studies suggest. During my lecture, I will report on recent findings from my lab regarding the role and regulation of the IL-23/IL-17 axis in response to Malassezia under normal and diseased skin conditions.