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1.
Cell ; 184(4): 1017-1031.e14, 2021 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-33548172

RESUMEN

Antibodies mediate natural and vaccine-induced immunity against viral and bacterial pathogens, whereas fungi represent a widespread kingdom of pathogenic species for which neither vaccine nor neutralizing antibody therapies are clinically available. Here, using a multi-kingdom antibody profiling (multiKAP) approach, we explore the human antibody repertoires against gut commensal fungi (mycobiota). We identify species preferentially targeted by systemic antibodies in humans, with Candida albicans being the major inducer of antifungal immunoglobulin G (IgG). Fungal colonization of the gut induces germinal center (GC)-dependent B cell expansion in extraintestinal lymphoid tissues and generates systemic antibodies that confer protection against disseminated C. albicans or C. auris infection. Antifungal IgG production depends on the innate immunity regulator CARD9 and CARD9+CX3CR1+ macrophages. In individuals with invasive candidiasis, loss-of-function mutations in CARD9 are associated with impaired antifungal IgG responses. These results reveal an important role of gut commensal fungi in shaping the human antibody repertoire through CARD9-dependent induction of host-protective antifungal IgG.


Asunto(s)
Anticuerpos Antifúngicos/inmunología , Proteínas Adaptadoras de Señalización CARD/metabolismo , Tracto Gastrointestinal/inmunología , Tracto Gastrointestinal/microbiología , Inmunidad , Inmunoglobulina G/inmunología , Micobioma/inmunología , Animales , Linfocitos B/inmunología , Candida albicans/inmunología , Candidiasis/inmunología , Candidiasis/microbiología , Heces/microbiología , Centro Germinal/inmunología , Humanos , Ratones Endogámicos C57BL , Fagocitos/metabolismo , Polimorfismo de Nucleótido Simple/genética , Unión Proteica , Transducción de Señal
2.
Nat Immunol ; 22(11): 1382-1390, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34663978

RESUMEN

Intergenerational inheritance of immune traits linked to epigenetic modifications has been demonstrated in plants and invertebrates. Here we provide evidence for transmission of trained immunity across generations to murine progeny that survived a sublethal systemic infection with Candida albicans or a zymosan challenge. The progeny of trained mice exhibited cellular, developmental, transcriptional and epigenetic changes associated with the bone marrow-resident myeloid effector and progenitor cell compartment. Moreover, the progeny of trained mice showed enhanced responsiveness to endotoxin challenge, alongside improved protection against systemic heterologous Escherichia coli and Listeria monocytogenes infections. Sperm DNA of parental male mice intravenously infected with the fungus C. albicans showed DNA methylation differences linked to immune gene loci. These results provide evidence for inheritance of trained immunity in mammals, enhancing protection against infections.


Asunto(s)
Candida albicans/inmunología , Candidiasis/inmunología , Infecciones por Escherichia coli/inmunología , Escherichia coli/inmunología , Herencia , Inmunidad Innata/genética , Listeria monocytogenes/inmunología , Listeriosis/inmunología , Células Mieloides/inmunología , Animales , Candida albicans/patogenicidad , Candidiasis/genética , Candidiasis/metabolismo , Candidiasis/microbiología , Células Cultivadas , Metilación de ADN , Modelos Animales de Enfermedad , Epigénesis Genética , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/genética , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Interacciones Huésped-Patógeno , Listeria monocytogenes/patogenicidad , Listeriosis/genética , Listeriosis/metabolismo , Listeriosis/microbiología , Masculino , Ratones Transgénicos , Células Mieloides/metabolismo , Células Mieloides/microbiología , Espermatozoides/inmunología , Espermatozoides/metabolismo , Transcripción Genética
3.
Nat Immunol ; 20(5): 546-558, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30911105

RESUMEN

Neutrophils are essential first-line defense cells against invading pathogens, yet when inappropriately activated, their strong immune response can cause collateral tissue damage and contributes to immunological diseases. However, whether neutrophils can intrinsically titrate their immune response remains unknown. Here we conditionally deleted the Spi1 gene, which encodes the myeloid transcription factor PU.1, from neutrophils of mice undergoing fungal infection and then performed comprehensive epigenomic profiling. We found that as well as providing the transcriptional prerequisite for eradicating pathogens, the predominant function of PU.1 was to restrain the neutrophil defense by broadly inhibiting the accessibility of enhancers via the recruitment of histone deacetylase 1. Such epigenetic modifications impeded the immunostimulatory AP-1 transcription factor JUNB from entering chromatin and activating its targets. Thus, neutrophils rely on a PU.1-installed inhibitor program to safeguard their epigenome from undergoing uncontrolled activation, protecting the host against an exorbitant innate immune response.


Asunto(s)
Epigénesis Genética/inmunología , Epigenómica/métodos , Neutrófilos/inmunología , Proteínas Proto-Oncogénicas/inmunología , Transactivadores/inmunología , Animales , Candida albicans/inmunología , Candida albicans/fisiología , Candidiasis/genética , Candidiasis/inmunología , Candidiasis/microbiología , Resistencia a la Enfermedad/genética , Resistencia a la Enfermedad/inmunología , Perfilación de la Expresión Génica/métodos , Humanos , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Neutrófilos/metabolismo , Neutrófilos/microbiología , Proteínas Proto-Oncogénicas/deficiencia , Proteínas Proto-Oncogénicas/genética , Análisis de Supervivencia , Transactivadores/deficiencia , Transactivadores/genética , Transcriptoma/genética , Transcriptoma/inmunología
4.
Nat Immunol ; 20(5): 559-570, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30996332

RESUMEN

The C-type lectin receptor-Syk (spleen tyrosine kinase) adaptor CARD9 facilitates protective antifungal immunity within the central nervous system (CNS), as human deficiency in CARD9 causes susceptibility to fungus-specific, CNS-targeted infection. CARD9 promotes the recruitment of neutrophils to the fungus-infected CNS, which mediates fungal clearance. In the present study we investigated host and pathogen factors that promote protective neutrophil recruitment during invasion of the CNS by Candida albicans. The cytokine IL-1ß served an essential function in CNS antifungal immunity by driving production of the chemokine CXCL1, which recruited neutrophils expressing the chemokine receptor CXCR2. Neutrophil-recruiting production of IL-1ß and CXCL1 was induced in microglia by the fungus-secreted toxin Candidalysin, in a manner dependent on the kinase p38 and the transcription factor c-Fos. Notably, microglia relied on CARD9 for production of IL-1ß, via both transcriptional regulation of Il1b and inflammasome activation, and of CXCL1 in the fungus-infected CNS. Microglia-specific Card9 deletion impaired the production of IL-1ß and CXCL1 and neutrophil recruitment, and increased fungal proliferation in the CNS. Thus, an intricate network of host-pathogen interactions promotes antifungal immunity in the CNS; this is impaired in human deficiency in CARD9, which leads to fungal disease of the CNS.


Asunto(s)
Proteínas Adaptadoras de Señalización CARD/inmunología , Candidiasis/inmunología , Quimiocina CXCL1/inmunología , Interleucina-1beta/inmunología , Microglía/inmunología , Neutrófilos/inmunología , Animales , Encéfalo/inmunología , Encéfalo/metabolismo , Encéfalo/microbiología , Proteínas Adaptadoras de Señalización CARD/genética , Proteínas Adaptadoras de Señalización CARD/metabolismo , Candida albicans/inmunología , Candida albicans/fisiología , Candidiasis/genética , Candidiasis/microbiología , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Citocinas/genética , Citocinas/inmunología , Citocinas/metabolismo , Interacciones Huésped-Patógeno/inmunología , Inflamasomas/genética , Inflamasomas/inmunología , Inflamasomas/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Ratones Noqueados , Ratones Transgénicos , Microglía/metabolismo , Microglía/microbiología , Infiltración Neutrófila/genética , Infiltración Neutrófila/inmunología , Neutrófilos/metabolismo , Neutrófilos/microbiología
5.
PLoS Biol ; 22(6): e3002693, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38905306

RESUMEN

Candida albicans is a commensal of the human microbiota that can form biofilms on implanted medical devices. These biofilms are tolerant to antifungals and to the host immune system. To identify novel genes modulating C. albicans biofilm formation, we performed a large-scale screen with 2,454 C. albicans doxycycline-dependent overexpression strains and identified 16 genes whose overexpression significantly hampered biofilm formation. Among those, overexpression of the ZCF15 and ZCF26 paralogs that encode transcription factors and have orthologs only in biofilm-forming species of the Candida clade, caused impaired biofilm formation both in vitro and in vivo. Interestingly, overexpression of ZCF15 impeded biofilm formation without any defect in hyphal growth. Transcript profiling, transcription factor binding, and phenotypic microarray analyses conducted upon overexpression of ZCF15 and ZCF26 demonstrated their role in reprogramming cellular metabolism by regulating central metabolism including glyoxylate and tricarboxylic acid cycle genes. Taken together, this study has identified a new set of biofilm regulators, including ZCF15 and ZCF26, that appear to control biofilm development through their specific role in metabolic remodeling.


Asunto(s)
Biopelículas , Candida albicans , Proteínas Fúngicas , Regulación Fúngica de la Expresión Génica , Factores de Transcripción , Biopelículas/crecimiento & desarrollo , Candida albicans/genética , Candida albicans/metabolismo , Candida albicans/fisiología , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Animales , Plancton/metabolismo , Glioxilatos/metabolismo , Perfilación de la Expresión Génica/métodos , Ratones , Ciclo del Ácido Cítrico , Hifa/metabolismo , Hifa/crecimiento & desarrollo , Hifa/genética , Candidiasis/microbiología , Reprogramación Metabólica
6.
PLoS Genet ; 20(5): e1011281, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38743788

RESUMEN

CgHog1, terminal kinase of the high-osmolarity glycerol signalling pathway, orchestrates cellular response to multiple external stimuli including surplus-environmental iron in the human fungal pathogen Candida glabrata (Cg). However, CgHog1 substrates remain unidentified. Here, we show that CgHog1 adversely affects Cg adherence to host stomach and kidney epithelial cells in vitro, but promotes Cg survival in the iron-rich gastrointestinal tract niche. Further, CgHog1 interactome and in vitro phosphorylation analysis revealed CgSub2 (putative RNA helicase) to be a CgHog1 substrate, with CgSub2 also governing iron homeostasis and host adhesion. CgSub2 positively regulated EPA1 (encodes a major adhesin) expression and host adherence via its interactor CgHtz1 (histone H2A variant). Notably, both CgHog1 and surplus environmental iron had a negative impact on CgSub2-CgHtz1 interaction, with CgHTZ1 or CgSUB2 deletion reversing the elevated adherence of Cghog1Δ to epithelial cells. Finally, the surplus-extracellular iron led to CgHog1 activation, increased CgSub2 phosphorylation, elevated CgSub2-CgHta (canonical histone H2A) interaction, and EPA1 transcriptional activation, thereby underscoring the iron-responsive, CgHog1-induced exchange of histone partners of CgSub2. Altogether, our work mechanistically defines how CgHog1 couples Epa1 adhesin expression with iron abundance, and point towards specific chromatin composition modification programs that probably aid fungal pathogens align their adherence to iron-rich (gut) and iron-poor (blood) host niches.


Asunto(s)
Candida glabrata , Adhesión Celular , Células Epiteliales , Proteínas Fúngicas , Histonas , Candida glabrata/genética , Candida glabrata/metabolismo , Humanos , Histonas/metabolismo , Histonas/genética , Células Epiteliales/microbiología , Células Epiteliales/metabolismo , Adhesión Celular/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Fosforilación , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/genética , Hierro/metabolismo , Regulación Fúngica de la Expresión Génica , Candidiasis/microbiología , Candidiasis/genética , Transducción de Señal
7.
PLoS Pathog ; 20(1): e1011902, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38166150

RESUMEN

Fungal infections have emerged as a major concern among immunocompromised patients, causing approximately 2 million deaths each year worldwide. However, the regulatory mechanisms underlying antifungal immunity remain elusive and require further investigation. The E3 ligase Trim26 belongs to the tripartite motif (Trim) protein family, which is involved in various biological processes, including cell proliferation, antiviral innate immunity, and inflammatory responses. Herein, we report that Trim26 exerts protective antifungal immune functions after fungal infection. Trim26-deficient mice are more susceptible to fungemia than their wild-type counterparts. Mechanistically, Trim26 restricts inflammatory neutrophils infiltration and limits proinflammatory cytokine production, which can attenuate kidney fungal load and renal damage during Candida infection. Trim26-deficient neutrophils showed higher proinflammatory cytokine expression and impaired fungicidal activity. We further demonstrated that excessive neutrophils infiltration in the kidney was because of the increased production of chemokines CXCL1 and CXCL2, which are mainly synthesized in the macrophages or dendritic cells of Trim26-deficient mice after Candida albicans infections. Together, our study findings unraveled the vital role of Trim26 in regulating antifungal immunity through the regulation of inflammatory neutrophils infiltration and proinflammatory cytokine and chemokine expression during candidiasis.


Asunto(s)
Candidiasis , Neutrófilos , Animales , Ratones , Antifúngicos , Candida albicans , Candidiasis/metabolismo , Candidiasis/microbiología , Citocinas/metabolismo , Infiltración Neutrófila , Proteínas de Motivos Tripartitos , Ubiquitina-Proteína Ligasas
8.
PLoS Pathog ; 20(6): e1012319, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38885290

RESUMEN

Candida albicans is a leading cause of intravascular catheter-related infections. The capacity for biofilm formation has been proposed to contribute to the persistence of this fungal pathogen on catheter surfaces. While efforts have been devoted to identifying microbial factors that modulate C. albicans biofilm formation in vitro, our understanding of the host factors that may shape C. albicans persistence in intravascular catheters is lacking. Here, we used multiphoton microscopy to characterize biofilms in intravascular catheters removed from candidiasis patients. We demonstrated that, NETosis, a type of neutrophil cell death with antimicrobial activity, was implicated in the interaction of immune cells with C. albicans in the catheters. The catheter isolates exhibited reduced filamentation and candidalysin gene expression, specifically in the total parenteral nutrition culture environment. Furthermore, we showed that the ablation of candidalysin expression in C. albicans reduced NETosis and conferred resistance to neutrophil-mediated fungal biofilm elimination. Our findings illustrate the role of neutrophil NETosis in modulating C. albicans biofilm persistence in an intravascular catheter, highlighting that C. albicans can benefit from reduced virulence expression to promote its persistence in an intravascular catheter.


Asunto(s)
Biopelículas , Candida albicans , Candidiasis , Infecciones Relacionadas con Catéteres , Trampas Extracelulares , Proteínas Fúngicas , Neutrófilos , Humanos , Biopelículas/crecimiento & desarrollo , Proteínas Fúngicas/metabolismo , Candidiasis/microbiología , Candidiasis/inmunología , Infecciones Relacionadas con Catéteres/microbiología , Neutrófilos/inmunología , Neutrófilos/metabolismo , Trampas Extracelulares/inmunología , Catéteres/microbiología , Regulación Fúngica de la Expresión Génica
9.
PLoS Pathog ; 20(4): e1012154, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38603707

RESUMEN

Candida albicans chronically colonizes the respiratory tract of patients with Cystic Fibrosis (CF). It competes with CF-associated pathogens (e.g. Pseudomonas aeruginosa) and contributes to disease severity. We hypothesize that C. albicans undergoes specific adaptation mechanisms that explain its persistence in the CF lung environment. To identify the underlying genetic and phenotypic determinants, we serially recovered 146 C. albicans clinical isolates over a period of 30 months from the sputum of 25 antifungal-naive CF patients. Multilocus sequence typing analyses revealed that most patients were individually colonized with genetically close strains, facilitating comparative analyses between serial isolates. We strikingly observed differential ability to filament and form monospecies and dual-species biofilms with P. aeruginosa among 18 serial isolates sharing the same diploid sequence type, recovered within one year from a pediatric patient. Whole genome sequencing revealed that their genomes were highly heterozygous and similar to each other, displaying a highly clonal subpopulation structure. Data mining identified 34 non-synonymous heterozygous SNPs in 19 open reading frames differentiating the hyperfilamentous and strong biofilm-former strains from the remaining isolates. Among these, we detected a glycine-to-glutamate substitution at position 299 (G299E) in the deduced amino acid sequence of the zinc cluster transcription factor ROB1 (ROB1G299E), encoding a major regulator of filamentous growth and biofilm formation. Introduction of the G299E heterozygous mutation in a co-isolated weak biofilm-former CF strain was sufficient to confer hyperfilamentous growth, increased expression of hyphal-specific genes, increased monospecies biofilm formation and increased survival in dual-species biofilms formed with P. aeruginosa, indicating that ROB1G299E is a gain-of-function mutation. Disruption of ROB1 in a hyperfilamentous isolate carrying the ROB1G299E allele abolished hyperfilamentation and biofilm formation. Our study links a single heterozygous mutation to the ability of C. albicans to better survive during the interaction with other CF-associated microbes and illuminates how adaptive traits emerge in microbial pathogens to persistently colonize and/or infect the CF-patient airways.


Asunto(s)
Biopelículas , Candida albicans , Fibrosis Quística , Proteínas Fúngicas , Factores de Transcripción , Fibrosis Quística/microbiología , Candida albicans/genética , Candida albicans/metabolismo , Humanos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Biopelículas/crecimiento & desarrollo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Mutación con Ganancia de Función , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Pulmón/microbiología , Candidiasis/microbiología , Adaptación Fisiológica
10.
PLoS Pathog ; 20(5): e1012225, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38739655

RESUMEN

Biofilm formation by the fungal pathogen Candida albicans is the basis for its ability to infect medical devices. The metabolic gene ERG251 has been identified as a target of biofilm transcriptional regulator Efg1, and here we report that ERG251 is required for biofilm formation but not conventional free-living planktonic growth. An erg251Δ/Δ mutation impairs biofilm formation in vitro and in an in vivo catheter infection model. In both in vitro and in vivo biofilm contexts, cell number is reduced and hyphal length is limited. To determine whether the mutant defect is in growth or some other aspect of biofilm development, we examined planktonic cell features in a biofilm-like environment, which was approximated with sealed unshaken cultures. Under those conditions, the erg251Δ/Δ mutation causes defects in growth and hyphal extension. Overexpression in the erg251Δ/Δ mutant of the paralog ERG25, which is normally expressed more weakly than ERG251, partially improves biofilm formation and biofilm hyphal content, as well as growth and hyphal extension in a biofilm-like environment. GC-MS analysis shows that the erg251Δ/Δ mutation causes a defect in ergosterol accumulation when cells are cultivated under biofilm-like conditions, but not under conventional planktonic conditions. Overexpression of ERG25 in the erg251Δ/Δ mutant causes some increase in ergosterol levels. Finally, the hypersensitivity of efg1Δ/Δ mutants to the ergosterol inhibitor fluconazole is reversed by ERG251 overexpression, arguing that reduced ERG251 expression contributes to this efg1Δ/Δ phenotype. Our results indicate that ERG251 is required for biofilm formation because its high expression levels are necessary for ergosterol synthesis in a biofilm-like environment.


Asunto(s)
Biopelículas , Candida albicans , Candidiasis , Proteínas Fúngicas , Biopelículas/crecimiento & desarrollo , Candida albicans/metabolismo , Candida albicans/genética , Candida albicans/fisiología , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Animales , Candidiasis/microbiología , Candidiasis/metabolismo , Hifa/metabolismo , Ratones , Regulación Fúngica de la Expresión Génica , Ergosterol/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Mutación
11.
Immunity ; 47(1): 148-158.e5, 2017 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-28709803

RESUMEN

Mucosal sites such as the intestine, oral cavity, nasopharynx, and vagina all have associated commensal flora. The surface of the eye is also a mucosal site, but proof of a living, resident ocular microbiome remains elusive. Here, we used a mouse model of ocular surface disease to reveal that commensals were present in the ocular mucosa and had functional immunological consequences. We isolated one such candidate commensal, Corynebacterium mastitidis, and showed that this organism elicited a commensal-specific interleukin-17 response from γδ T cells in the ocular mucosa that was central to local immunity. The commensal-specific response drove neutrophil recruitment and the release of antimicrobials into the tears and protected the eye from pathogenic Candida albicans or Pseudomonas aeruginosa infection. Our findings provide direct evidence that a resident commensal microbiome exists on the ocular surface and identify the cellular mechanisms underlying its effects on ocular immune homeostasis and host defense.


Asunto(s)
Candida albicans/inmunología , Candidiasis/inmunología , Córnea/inmunología , Infecciones por Corynebacterium/inmunología , Corynebacterium/inmunología , Infecciones del Ojo/inmunología , Inmunidad Mucosa , Interleucina-17/metabolismo , Microbiota/inmunología , Neutrófilos/inmunología , Infecciones por Pseudomonas/inmunología , Pseudomonas aeruginosa/inmunología , Linfocitos T/inmunología , Lágrimas/inmunología , Animales , Candidiasis/microbiología , Córnea/microbiología , Infecciones por Corynebacterium/microbiología , Modelos Animales de Enfermedad , Infecciones del Ojo/microbiología , Interacciones Huésped-Patógeno , Humanos , Interleucina-17/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Infiltración Neutrófila , Neutrófilos/microbiología , Infecciones por Pseudomonas/microbiología , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo
12.
PLoS Pathog ; 19(12): e1011843, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38127686

RESUMEN

Candida auris recently emerged as an urgent public health threat, causing outbreaks of invasive infections in healthcare settings throughout the world. This fungal pathogen persists on the skin of patients and on abiotic surfaces despite antiseptic and decolonization attempts. The heightened capacity for skin colonization and environmental persistence promotes rapid nosocomial spread. Following skin colonization, C. auris can gain entrance to the bloodstream and deeper tissues, often through a wound or an inserted medical device, such as a catheter. C. auris possesses a variety of virulence traits, including the capacity for biofilm formation, production of adhesins and proteases, and evasion of innate immune responses. In this review, we highlight the interactions of C. auris with the host, emphasizing the intersection of laboratory studies and clinical observations.


Asunto(s)
Candida , Candidiasis , Humanos , Candidiasis/microbiología , Virulencia , Candida auris , Brotes de Enfermedades , Antifúngicos
13.
PLoS Pathog ; 19(10): e1011698, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37856418

RESUMEN

Candida auris, is an emerging fungal pathogen that can cause life-threatening infections in humans. Unlike many other Candida species that colonize the intestine, C. auris most efficiently colonizes the skin. Such colonization contaminates the patient's environment and can result in rapid nosocomial transmission. In addition, this transmission can lead to outbreaks of systemic infections that have mortality rates between 40% and 60%. C. auris isolates resistant to all known classes of antifungals have been identified and as such, understanding the underlying biochemical mechanisms of how skin colonization initiates and progresses is critical to developing better therapeutic options. With this review, we briefly summarize what is known about horizontal transmission and current tools used to identify, understand, and control C. auris infections.


Asunto(s)
Candidiasis , Humanos , Candidiasis/microbiología , Candida auris , Candida , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Brotes de Enfermedades , Pruebas de Sensibilidad Microbiana
14.
PLoS Pathog ; 19(6): e1011478, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37363924

RESUMEN

Metals such as Fe, Cu, Zn, and Mn are essential trace nutrients for all kingdoms of life, including microbial pathogens and their hosts. During infection, the mammalian host attempts to starve invading microbes of these micronutrients through responses collectively known as nutritional immunity. Nutritional immunity for Zn, Fe and Cu has been well documented for fungal infections; however Mn handling at the host-fungal pathogen interface remains largely unexplored. This work establishes the foundation of fungal resistance against Mn associated nutritional immunity through the characterization of NRAMP divalent metal transporters in the opportunistic fungal pathogen, Candida albicans. Here, we identify C. albicans Smf12 and Smf13 as two NRAMP transporters required for cellular Mn accumulation. Single or combined smf12Δ/Δ and smf13Δ/Δ mutations result in a 10-80 fold reduction in cellular Mn with an additive effect of double mutations and no losses in cellular Cu, Fe or Zn. As a result of low cellular Mn, the mutants exhibit impaired activity of mitochondrial Mn-superoxide dismutase 2 (Sod2) and cytosolic Mn-Sod3 but no defects in cytosolic Cu/Zn-Sod1 activity. Mn is also required for activity of Golgi mannosyltransferases, and smf12Δ/Δ and smf13Δ/Δ mutants show a dramatic loss in cell surface phosphomannan and in glycosylation of proteins, including an intracellular acid phosphatase and a cell wall Cu-only Sod5 that is key for oxidative stress resistance. Importantly, smf12Δ/Δ and smf13Δ/Δ mutants are defective in formation of hyphal filaments, a deficiency rescuable by supplemental Mn. In a disseminated mouse model for candidiasis where kidney is the primary target tissue, we find a marked loss in total kidney Mn during fungal invasion, implying host restriction of Mn. In this model, smf12Δ/Δ and smf13Δ/Δ C. albicans mutants displayed a significant loss in virulence. These studies establish a role for Mn in Candida pathogenesis.


Asunto(s)
Candida albicans , Candidiasis , Ratones , Animales , Candida albicans/metabolismo , Manganeso/metabolismo , Candidiasis/microbiología , Candida , Morfogénesis , Proteínas Fúngicas/metabolismo , Mamíferos
15.
PLoS Biol ; 20(8): e3001762, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35976859

RESUMEN

Candida albicans biofilms are a complex multilayer community of cells that are resistant to almost all classes of antifungal drugs. The bottommost layers of biofilms experience nutrient limitation where C. albicans cells are required to respire. We previously reported that a protein Ndu1 is essential for Candida mitochondrial respiration; loss of NDU1 causes inability of C. albicans to grow on alternative carbon sources and triggers early biofilm detachment. Here, we screened a repurposed library of FDA-approved small molecule inhibitors to identify those that prevent NDU1-associated functions. We identified an antihelminthic drug, Niclosamide (NCL), which not only prevented growth on acetate, C. albicans hyphenation and early biofilm growth, but also completely disengaged fully grown biofilms of drug-resistant C. albicans and Candida auris from their growth surface. To overcome the suboptimal solubility and permeability of NCL that is well known to affect its in vivo efficacy, we developed NCL-encapsulated Eudragit EPO (an FDA-approved polymer) nanoparticles (NCL-EPO-NPs) with high niclosamide loading, which also provided long-term stability. The developed NCL-EPO-NPs completely penetrated mature biofilms and attained anti-biofilm activity at low microgram concentrations. NCL-EPO-NPs induced ROS activity in C. albicans and drastically reduced oxygen consumption rate in the fungus, similar to that seen in an NDU1 mutant. NCL-EPO-NPs also significantly abrogated mucocutaneous candidiasis by fluconazole-resistant strains of C. albicans, in mice models of oropharyngeal and vulvovaginal candidiasis. To our knowledge, this is the first study that targets biofilm detachment as a target to get rid of drug-resistant Candida biofilms and uses NPs of an FDA-approved nontoxic drug to improve biofilm penetrability and microbial killing.


Asunto(s)
Candidiasis , Nanopartículas , Animales , Antifúngicos/farmacología , Biopelículas , Candida , Candida albicans , Candidiasis/microbiología , Fluconazol/farmacología , Ratones , Pruebas de Sensibilidad Microbiana , Niclosamida/farmacología , Niclosamida/uso terapéutico
16.
Cell Mol Life Sci ; 81(1): 280, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918243

RESUMEN

Candida albicans is among the most prevalent invasive fungal pathogens for immunocompromised individuals and novel therapeutic approaches that involve immune response modulation are imperative. Absent in melanoma 2 (AIM2), a pattern recognition receptor for DNA sensing, is well recognized for its involvement in inflammasome formation and its crucial role in safeguarding the host against various pathogenic infections. However, the role of AIM2 in host defense against C. albicans infection remains uncertain. This study reveals that the gene expression of AIM2 is induced in human and mouse innate immune cells or tissues after C. albicans infection. Furthermore, compared to their wild-type (WT) counterparts, Aim2-/- mice surprisingly exhibit resistance to C. albicans infection, along with reduced inflammation in the kidneys post-infection. The resistance of Aim2-/- mice to C. albicans infection is not reliant on inflammasome or type I interferon production. Instead, Aim2-/- mice display lower levels of apoptosis in kidney tissues following infection than WT mice. The deficiency of AIM2 in macrophages, but not in dendritic cells, results in a phenocopy of the resistance observed in Aim2-/- mice against C. albican infection. The treatment of Clodronate Liposome, a reagent that depletes macrophages, also shows the critical role of macrophages in host defense against C. albican infection in Aim2-/- mice. Furthermore, the reduction in apoptosis is observed in Aim2-/- mouse macrophages following infection or treatment of DNA from C. albicans in comparison with controls. Additionally, higher levels of AKT activation are observed in Aim2-/- mice, and treatment with an AKT inhibitor reverses the host resistance to C. albicans infection. The findings collectively demonstrate that AIM2 exerts a negative regulatory effect on AKT activation and enhances macrophage apoptosis, ultimately compromising host defense against C. albicans infection. This suggests that AIM2 and AKT may represent promising therapeutic targets for the management of fungal infections.


Asunto(s)
Apoptosis , Candida albicans , Candidiasis , Proteínas de Unión al ADN , Macrófagos , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Animales , Macrófagos/metabolismo , Macrófagos/inmunología , Macrófagos/microbiología , Candidiasis/inmunología , Candidiasis/microbiología , Candidiasis/metabolismo , Candidiasis/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratones , Humanos , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Inflamasomas/metabolismo , Inmunidad Innata , Riñón/patología , Riñón/metabolismo , Riñón/microbiología
17.
J Proteome Res ; 23(5): 1634-1648, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38572994

RESUMEN

The delay in making a correct diagnosis of Candida auris causes concern in the healthcare system setting, and immunoproteomics studies are important to identify immunoreactive proteins for new diagnostic strategies. In this study, immunocompetent murine systemic infections caused by non-aggregative and aggregative phenotypes of C. auris and by Candida albicans and Candida haemulonii were carried out, and the obtained sera were used to study their immunoreactivity against C. auris proteins. The results showed higher virulence, in terms of infection signs, weight loss, and histopathological damage, of the non-aggregative isolate. Moreover, C. auris was less virulent than C. albicans but more than C. haemulonii. Regarding the immunoproteomics study, 13 spots recognized by sera from mice infected with both C. auris phenotypes and analyzed by mass spectrometry corresponded to enolase, phosphoglycerate kinase, glyceraldehyde-3-phosphate dehydrogenase, and phosphoglycerate mutase. These four proteins were also recognized by sera obtained from human patients with disseminated C. auris infection but not by sera obtained from mice infected with C. albicans or Aspergillus fumigatus. Spot identification data are available via ProteomeXchange with the identifier PXD049077. In conclusion, this study showed that the identified proteins could be potential candidates to be studied as new diagnostic or even therapeutic targets for C. auris.


Asunto(s)
Candida , Candidiasis , Inmunoglobulina G , Animales , Ratones , Candida/inmunología , Candida/patogenicidad , Humanos , Candidiasis/inmunología , Candidiasis/microbiología , Candidiasis/sangre , Inmunoglobulina G/sangre , Antígenos Fúngicos/inmunología , Antígenos Fúngicos/sangre , Proteómica/métodos , Candida albicans/inmunología , Candida albicans/patogenicidad , Proteínas Fúngicas/inmunología , Fosfoglicerato Mutasa/inmunología , Fosfoglicerato Quinasa/inmunología , Gliceraldehído-3-Fosfato Deshidrogenasas/inmunología , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Anticuerpos Antifúngicos/sangre , Anticuerpos Antifúngicos/inmunología , Femenino , Virulencia
18.
Infect Immun ; 92(6): e0010324, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38722168

RESUMEN

Candida auris is an opportunistic fungal pathogen with high mortality rates which presents a clear threat to public health. The risk of C. auris infection is high because it can colonize the body, resist antifungal treatment, and evade the immune system. The genetic mechanisms for these traits are not well known. Identifying them could lead to new targets for new treatments. To this end, we present an analysis of the genetics and gene expression patterns of C. auris carbon metabolism, drug resistance, and macrophage interaction. We chose to study two C. auris isolates simultaneously, one drug sensitive (B11220 from Clade II) and one drug resistant (B11221 from Clade III). Comparing the genomes, we confirm the previously reported finding that B11220 was missing a 12.8 kb region on chromosome VI. This region contains a gene cluster encoding proteins related to alternative sugar utilization. We show that B11221, which has the gene cluster, readily assimilates and utilizes D-galactose and L-rhamnose as compared to B11220, which harbors the deletion. B11221 exhibits increased adherence and drug resistance compared to B11220 when grown in these sugars. Transcriptomic analysis of both isolates grown on glucose or galactose showed that the gene cluster was upregulated when grown on D-galactose. These findings reinforce growing evidence of a link between metabolism and drug tolerance. B11221 resists phagocytosis by macrophages and exhibits decreased ß-1,3-glucan exposure, a key determinant that allows Candida to evade the host immune system, as compared to B11220. In a transcriptomic analysis of both isolates co-cultured with macrophages, we find upregulation of genes associated with transport and transcription factors in B11221. Our studies show a positive correlation between membrane composition and immune evasion, alternate sugar utilization, and drug tolerance in C. auris.


Asunto(s)
Antifúngicos , Candida auris , Virulencia/genética , Candida auris/genética , Candida auris/efectos de los fármacos , Antifúngicos/farmacología , Candidiasis/microbiología , Candidiasis/inmunología , Farmacorresistencia Fúngica/genética , Genoma Fúngico , Humanos , Macrófagos/microbiología , Macrófagos/inmunología , Regulación Fúngica de la Expresión Génica , Perfilación de la Expresión Génica , Animales
19.
Infect Immun ; 92(7): e0007224, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38899880

RESUMEN

Invasive fungal infections impose an enormous clinical, social, and economic burden on humankind. One of the most common species responsible for invasive fungal infections is Candida albicans. More than 30% of patients with disseminated candidiasis fail therapy with existing antifungal drugs, including the widely used azole class. We previously identified a collection of 13 medications that antagonize the activity of the azoles on C. albicans. Although gain-of-function mutations responsible for antifungal resistance are often associated with reduced fitness and virulence, it is currently unknown how exposure to azole antagonistic drugs impacts C. albicans physiology, fitness, or virulence. In this study, we examined how exposure to seven azole antagonists affects C. albicans phenotype and capacity to cause disease. Most of the azole antagonists appear to have little impact on fungal growth, morphology, stress tolerance, or gene transcription. However, aripiprazole had a modest impact on C. albicans hyphal growth and increased cell wall chitin content. It also aggravated the disseminated C. albicans infections in mice. This effect was abrogated in immunosuppressed mice, indicating that it is at least in part dependent upon host immune responses. Collectively, these data provide proof of principle that unanticipated drug-fungus interactions have the potential to influence the incidence and outcomes of invasive fungal disease.


Asunto(s)
Antifúngicos , Aripiprazol , Candida albicans , Candidiasis , Candida albicans/efectos de los fármacos , Candida albicans/genética , Animales , Ratones , Antifúngicos/farmacología , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología , Aripiprazol/farmacología , Aripiprazol/uso terapéutico , Antipsicóticos/farmacología , Antipsicóticos/uso terapéutico , Virulencia , Femenino , Azoles/farmacología , Modelos Animales de Enfermedad
20.
Emerg Infect Dis ; 30(13): S36-S40, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38561642

RESUMEN

Candida auris is an emerging fungal pathogen that typically affects patients in healthcare settings. Data on C. auris cases in correctional facilities are limited but are needed to guide public health recommendations. We describe cases and challenges of providing care for 13 patients who were transferred to correctional facilities during January 2020-December 2022 after having a positive C. auris specimen. All patients had positive specimens identified while receiving inpatient care at healthcare facilities in geographic areas with high C. auris prevalence. Correctional facilities reported challenges managing patients and implementing prevention measures; those challenges varied by whether patients were housed in prison medical units or general population units. Although rarely reported, C. auris cases in persons who are incarcerated may occur, particularly in persons with known risk factors. Measures to manage cases and prevent C. auris spread in correctional facilities should address setting-specific challenges in healthcare and nonhealthcare correctional environments.


Asunto(s)
Candida , Candidiasis , Humanos , Candidiasis/microbiología , Candida auris , Antifúngicos/uso terapéutico , Instalaciones Correccionales
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