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1.
J Investig Med High Impact Case Rep ; 12: 23247096241244729, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577759

RESUMO

This case centers on a 76-year-old male experiencing exertional dyspnea and hemoptysis, with a medical history marked by recurrent pulmonary embolism and chronic obstructive pulmonary disease (COPD). Notably, he resides in a histoplasmosis-endemic area. A computed tomography (CT) pulmonary embolism scan revealed notable findings, including an enlarged right lower pulmonary artery, vascular congestion, atelectasis, and a mass exerting pressure on the right lower pulmonary vein. Biopsy results identified the mass as fibrosing mediastinitis, likely attributed to histoplasmosis. A transthoracic echocardiogram indicated right ventricular dilatation, impaired function, and a right ventricular systolic pressure of 63 mm Hg. During right heart catheterization, the patient displayed disparate pulmonary artery wedge pressures (PAWPs) between the right and left sides. This discrepancy was linked to a blunted back wave from the left atrium to the catheter, induced by pulmonary vein compression. Although an infrequent phenomenon, the recorded asymmetry in PAWPs played a crucial role in guiding accurate patient management. The absence of subsequent evaluation of PAWP on the left side could have altered the treatment plan, potentially delaying appropriate patient care. This case emphasizes the necessity of thorough exploration with right heart catheterization when clinical symptoms warrant, highlighting the importance of standardized practices in such procedures.


Assuntos
Histoplasmose , Mediastinite , Embolia Pulmonar , Esclerose , Estenose de Veia Pulmonar , Masculino , Humanos , Idoso , Estenose de Veia Pulmonar/diagnóstico , Estenose de Veia Pulmonar/diagnóstico por imagem , Histoplasmose/complicações , Mediastinite/complicações , Mediastinite/diagnóstico , Fibrose , Embolia Pulmonar/complicações
2.
BMC Infect Dis ; 24(1): 406, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627642

RESUMO

BACKGROUND: Opportunistic infections (OIs) are common causes of mortality among people living with HIV (PLHIV). We determined prevalence and 30-day mortality due to histoplasmosis, cryptococcosis, and TB in PLHIV with advanced HIV disease (AHD). METHODS: PLHIV 18 years and older, with a CD4 + T-cell count of less than 350 cells/mm3 newly diagnosed with HIV infection or re-engaged in care after being without ART for more than 90 days (Group A). The second group included symptomatic PLHIV regardless of ART status or CD4 + T-cell count (Group B); all followed for 30 days. Detection of Histoplasma Ag (HisAg) in urine was done by enzyme immunoassay (EIA), Cryptococcus antigen (CrAg) was detected in serum and cerebrospinal fluid (CSF) specimens by lateral flow assay (LFA), and lipoarabinomannan (LAM) detection in urine was by LFA (TB LAM) and in sputum by GeneXpert for diagnosis of Mycobacterium infections. RESULTS: From August 2021 to June 2022, 491 PLHIV were enrolled; 482 (98%) had a CD4 + T-cell result, and 381 patients (79%) were classified with AHD according to CD4 + T-cell count (< 200 CD4/mm3). Frequency of an OI was 38% (n = 145/381). Antigen test positivity rate was 16% (72/467) for TB-LAM, 9% (43/464) for HisAg, and 11% (51/484) for CrAg. Twenty-one of 34 (62%) patients receiving CSF CrAg tests were positive, confirming meningitis. Significant differences in 30-day mortality were observed in patients with an OI (16%) vs. no OI (7%) (p = 0.002). Mortality was highest in patients with histoplasmosis (25%), co-infection (22%), cryptococcosis (18% overall; 19% for cryptococcal meningitis), and TB (10%). CONCLUSIONS: TB and fungal OIs, including co-infection, were common in PLHIV in Paraguay and had high associated mortality. Laboratories and health facilities need access to CD4 + T-cell testing and rapid diagnostic assays.


Assuntos
Coinfecção , Criptococose , Infecções por HIV , Histoplasmose , Infecções Oportunistas , Tuberculose , Humanos , Infecções por HIV/epidemiologia , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Testes de Diagnóstico Rápido , Paraguai/epidemiologia , Criptococose/complicações , Criptococose/diagnóstico , Criptococose/epidemiologia , Tuberculose/complicações , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Antígenos de Fungos
3.
Actual. Sida Infectol. (En linea) ; 32(114): 79-83, 20240000. fig
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1552337

RESUMO

La histoplasmosis es una micosis sistémica producida por una variedad de hongo dimorfo perteneciente al complejo Histoplasma capsulatum. Es una enfermedad prevalente en nuestro medio y sobre todo en pacientes viviendo con HIV con recuento de <200 linfocitos CD4/ml y con cargas virales mayores a 100.000 copias/ml. La presentación de la forma diseminada raramente suele afectar al aparato reproductor; siendo la forma más frecuente pulmonar


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Testículo/fisiopatologia , Histoplasmose/terapia , Sistema Imunitário/patologia
5.
MMWR Morb Mortal Wkly Rep ; 73(11): 239-244, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512795

RESUMO

Coccidioidomycosis, histoplasmosis, and blastomycosis are lower respiratory tract fungal infections whose signs and symptoms can resemble those of other respiratory illnesses, including pneumonia caused by bacterial or viral etiologies; this overlap in clinical presentation might lead to missed or delayed diagnoses. The causative fungi live in the environment, often in soil or plant matter. To describe the epidemiologic characteristics of cases of coccidioidomycosis, histoplasmosis, and blastomycosis during the COVID-19 pandemic, CDC analyzed case surveillance data for 2019-2021. During this period, a total of 59,655 coccidioidomycosis cases, 3,595 histoplasmosis cases, and 719 blastomycosis cases were reported to CDC. In 2020, fewer cases of each disease occurred in spring compared with other seasons, and most cases occurred in fall; national seasonality is not typically observed, and cases were seasonally distributed more evenly in 2019 and 2021. Fewer cases coinciding with the start of the COVID-19 pandemic, along with an unusually high blastomycosis case fatality rate in 2021 (17% compared with more typical rates of 8%-10%), suggest that the pandemic might have affected patients' health care-seeking behavior, public health reporting practices, or clinical management of these diseases. Increased awareness and education are needed to encourage health care providers to consider fungal diseases and to identify pneumonia of fungal etiology. Standardized diagnostic guidance and informational resources for fungal testing could be incorporated into broader respiratory disease awareness and preparedness efforts to improve early diagnosis of coccidioidomycosis, histoplasmosis, and blastomycosis.


Assuntos
Blastomicose , COVID-19 , Coccidioidomicose , Histoplasmose , Infecções Respiratórias , Humanos , Estados Unidos/epidemiologia , Blastomicose/epidemiologia , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Coccidioidomicose/diagnóstico , Coccidioidomicose/epidemiologia , Pandemias , COVID-19/epidemiologia , Infecções Respiratórias/epidemiologia
6.
Med Mycol ; 62(4)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38479779

RESUMO

Definitive diagnosis of histoplasmosis relies on culture and/or cytology/histopathology; however, these procedures have limited sensitivity and cultures are time-consuming. Antibodies detection by immunodiffusion has low sensitivity in immunocompromised individuals and uses histoplasmin (HMN), a crude antigenic extract, as reagent. Novel protein antigen candidates have been recently identified and produced by DNA-recombinant techniques to obtain standardized and specific reagents for diagnosing histoplasmosis. To compare the analytical performance of novel enzyme-linked immunosorbent assays (ELISAs) for antibodies testing for diagnosing histoplasmosis using different Histoplasma capsulatum antigens as reagents. The H. capsulatum 100 kDa protein (Hcp100), the M antigen and its immunoreactive fragment F1 were produced by DNA-recombinant techniques. Galactomannan was purified from both the yeast and mycelial cell walls (yGM and mGM, respectively). The analytical performance of the ELISA tests for the serological detection of antibodies against these antigens was evaluated and compared with those obtained using HMN as reagent. Antibodies detection by the Hcp100 ELISA demonstrated 90.0% sensitivity and 92.0% specificity, versus 43.3% sensitivity and 95.0% specificity of the M ELISA, 33.3% sensitivity and 84.0% specificity of the F1 ELISA, 96.7% sensitivity and 94.0% specificity of the yGM ELISA, 83.3% sensitivity and 88.0% specificity of the mGM ELISA, and 70.0% sensitivity and 86.0% specificity for the HMN ELISA. In summary, Hcp100 is proposed as the most promising candidate for the serodiagnosis of histoplasmosis. The primary immunoreactive element in HMN proved to be GM rather than the M antigen. Nevertheless, a higher incidence of cross-reactions was noted with GM compared to M.


Hcp100 is a promising serodiagnostic candidate for histoplasmosis, boasting high sensitivity and specificity. Notably, GM, rather than M antigen, emerged as the primary immunoreactive element in HMN, despite a higher incidence of cross-reactions with GM compared to M.


Assuntos
Histoplasmose , Humanos , Histoplasmose/diagnóstico , Histoplasmose/veterinária , Histoplasma/genética , Anticorpos Antifúngicos , Técnicas Imunoenzimáticas , Antígenos de Fungos , Anticorpos , Imunodifusão/veterinária , Saccharomyces cerevisiae , DNA
7.
Washington, D.C.; PAHO; 2024-03-22. (PAHO/UFCSPA/CDE/HT/23-0015).
Não convencional em Inglês | PAHO-IRIS | ID: phr-59381

RESUMO

People living with HIV (PLHIV) with severe advanced disease are at high risk of developing opportunistic infections and may face barriers related to diagnosis and treatment. The objective of this study was to describe insights, experiences and perspectives around the feasibility of implementing a package for the rapid diagnosis of frequent opportunistic infections among patients with advanced HIV, in order to support the development and implementation of HIV care policies. The study was carried out between June 30 and October 30, 2023, comprising two focus groups with health professionals involved in the rapid diagnosis intervention (n=10); four in-depth interviews with health managers dedicated to HIV care policies; and 12 interviews with patients with advanced HIV. The intervention in question was considered relevant for allowing a more timely diagnosis of diseases that are difficult to investigate. Patient compliance was generally collaborative, especially in research hospitals, but more vulnerable patients may require expanded psychosocial support. Among the barriers, delays in results, communication challenges between professionals and patients were highlighted, as well as the lack of alignment in the flow of exam request, collection, results and communication for patients and the extended team. At the management level, the importance of integrating the intervention into the line of care for patients with HIV was highlighted. It is relevant to investigate the issue of social determinants of HIV/AIDS mortality in the future to provide valuable insights into improving prevention and treatment strategies.


Assuntos
Tuberculose , Histoplasmose , Criptococose , HIV , Síndrome de Imunodeficiência Adquirida , Infecções Oportunistas , Política de Saúde , Doenças Transmissíveis , Brasil
8.
J Infect Dev Ctries ; 18(2): 318-325, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38484351

RESUMO

INTRODUCTION: Pulmonary histoplasmosis is a fungal disease that is endemic in North and Central America. It is relatively rare in China and commonly misdiagnosed as tuberculosis or cancer due to nonspecific clinical and radiographic manifestations. Rapid and accurate pathogen tests are critical for the diagnosis of pulmonary histoplasmosis. METHODOLOGY: We report two cases of pulmonary histoplasmosis. We collected all the relevant case reports on the Chinese mainland (from 1990 to 2022) to analyze features of this disease among Chinese patients. RESULTS: A total of 42 articles reporting 101 cases were identified, and the two cases reported in this article were also included for analysis. Sixty-three (61.2%) patients had respiratory symptoms and 35 (34.0%) patients were asymptomatic. The most common radiographic findings were pulmonary nodules or masses (81.6%). Twenty-two (21.4%) patients were misdiagnosed as tuberculosis, and 37 (35.9%) were misdiagnosed as lung tumors before pathological findings. Metagenomic next­generation sequencing (mNGS) testing provided a rapid diagnostic and therapeutic basis for three patients. CONCLUSIONS: Clinical features and imaging findings of pulmonary histoplasmosis are not specific. Relevant epidemiological history and timely pathogen detection are important for diagnosis. mNGS can shorten the time required for diagnosis and allow earlier initiation of targeted antibiotic therapy.


Assuntos
Histoplasmose , Pneumopatias Fúngicas , Pneumonia , Tuberculose , Humanos , Histoplasmose/diagnóstico , Histoplasmose/tratamento farmacológico , Histoplasmose/patologia , Histoplasma , Pneumopatias Fúngicas/diagnóstico por imagem , Pneumopatias Fúngicas/tratamento farmacológico
9.
Emerg Microbes Infect ; 13(1): 2315960, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38465644

RESUMO

ABSTRACTHistoplasmosis is an endemic mycosis in North America frequently reported along the Ohio and Mississippi River Valleys, although autochthonous cases occur in non-endemic areas. In the United States, the disease is provoked by two genetically distinct clades of Histoplasma capsulatum sensu lato, Histoplasma mississippiense (Nam1) and H. ohiense (Nam2). To bridge the molecular epidemiological gap, we genotyped 93 Histoplasma isolates (62 novel genomes) including clinical, environmental, and veterinarian samples from a broader geographical range by whole-genome sequencing, followed by evolutionary and species niche modelling analyses. We show that histoplasmosis is caused by two major lineages, H. ohiense and H. mississippiense; with sporadic cases caused by H. suramericanum in California and Texas. While H. ohiense is prevalent in eastern states, H. mississipiense was found to be prevalent in the central and western portions of the United States, but also geographically overlapping in some areas suggesting that these species might co-occur. Species Niche Modelling revealed that H. ohiense thrives in places with warmer and drier conditions, while H. mississippiense is endemic to areas with cooler temperatures and more precipitation. In addition, we predicted multiple areas of secondary contact zones where the two species co-occur, potentially facilitating gene exchange and hybridization. This study provides the most comprehensive understanding of the genomic epidemiology of histoplasmosis in the USA and lays a blueprint for the study of invasive fungal diseases.


Assuntos
Histoplasmose , Histoplasmose/epidemiologia , Histoplasma/genética , Genótipo , Genômica , Texas
11.
Microbiol Spectr ; 12(4): e0310023, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38411051

RESUMO

Histoplasma capsulatum var. farciminosum (HCF) is a dimorphic fungus that causes epizootic lymphangitis in equids. Current diagnostic approaches, including culture, microscopy, and clinical presentation, lack speed, sensitivity, and specificity when diagnosing clinical cases. In this study, equine blood and pus samples on Whatman FTA cards from Senegal (n = 3), The Gambia (n = 19), Ethiopia (n = 16), and Mali (n = 13) were tested using a real-time PCR (qPCR) protocol. The assay was optimized and tested for its suitability to detect and quantify HCF in blood and pus loaded onto Whatman FTA cards at sampling. Whatman FTA cards were tested for their suitability for use with qPCR and were found to recover DNA more efficiently than from direct extraction. Using TaqMan fluorescent probes and specific primers, the assay demonstrated 100% analytical specificity when detecting multiple strains of Histoplasma and no false positives with off-target organisms. The assay's diagnostic performance was measured against an existing nested internal transcribed spacer PCR protocol using a receiver operating characteristic curve. The test was found to have a diagnostic specificity and sensitivity of 100% and 71.4%, respectively, when analyzing pus samples using a cycle threshold (Ct) cutoff determined by Youden's index (27.75). Blood sample cutoff Ct value was proposed at 34.55. Further optimization is required to improve the performance of the protocol when applied to blood samples. This study has, for the first time, demonstrated the ability to detect and quantify the DNA of Histoplasma spp. in equine blood and pus samples with a high degree of accuracy, providing a platform to further investigate the pathogenesis and epidemiology of this disease. IMPORTANCE: Histoplasmosis is a neglected yet major cause of morbidity and mortality in both equids and people in resource-scarce settings. One of the major hindrances to the control of histoplasmosis is a lack of readily available diagnostic tests. Tests are needed to support clinical decision-making and to be applied in population-based research to further understand this disease in situ. This paper reports, for the first time, the validation and application of a qPCR to detect Histoplasma directly from equine clinical samples, bypassing the need to culture this notoriously difficult organism. We report and comment on the performance of the qPCR in comparison with our previously developed nested PCR.


Assuntos
Histoplasmose , Ácidos Nucleicos , Cavalos/genética , Animais , Humanos , Histoplasma/genética , Histoplasmose/diagnóstico , Histoplasmose/veterinária , Histoplasmose/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , DNA Fúngico/genética , Supuração
12.
J Equine Vet Sci ; 134: 105012, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38320735

RESUMO

In Sub-Saharan Africa (SSA), particularly in Ethiopia, Epizootic Lymphangitis (EL) is the most prevalent fungal disease of equids, which causes significant economic losses as well as a decrease in equid populations. Therefore, this systematic review and meta-analysis were designed to pool the results of individual studies and estimate the prevalence of EL among equids in Ethiopia. A systematic search of research articles on the prevalence and risk factors of EL among equids in Ethiopia was conducted in registers, databases, and other sources. Cochrane's Q, inverse variance (I2), sensitivity analysis, funnel plot, Begg's, and Egger's regression tests were used to check heterogeneity and publication bias. A random-effects model was used to calculate the pooled burden of EL among equids. For this meta-analysis, a total of 7217 equids were included in the 14 eligible studies. The overall pooled prevalence of EL among equids in Ethiopia was 20.24% (95% CI: 16.27, 24.21). According to the subgroup analysis, the highest prevalence was observed in cart horses (20.98%), the Amhara region (21.46%), and studies conducted using sample sizes of 384 equids or greater (24.67%) and from 2002 to 2018 (25.52%) study periods. Harness-inflicted wounds, sharing stables or yards with harnesses, and the presence of preexisting wounds were identified as factors significantly associated with EL magnitude. Early diagnosis and proper medication, as well as implementing appropriate prevention and control measures, are necessary for the management of EL in equids.


Assuntos
Histoplasmose , Doenças dos Cavalos , Linfangite , Cavalos , Animais , Etiópia/epidemiologia , Linfangite/epidemiologia , Linfangite/veterinária , Linfangite/diagnóstico , Prevalência , Histoplasmose/diagnóstico , Histoplasmose/microbiologia , Histoplasmose/veterinária , Fatores de Risco , Doenças dos Cavalos/diagnóstico
13.
Med Mycol ; 62(3)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38383897

RESUMO

In Ghana, most laboratory diagnoses of severe mycoses are based on histopathology findings due to inadequate availability of serology, culture, and molecular tests. The aim of this study was to evaluate the spectrum of mycoses diagnosed in Ghana. We retrospectively reviewed reports from 2012 to 2021 from three major pathology laboratories in Ghana to identify reports indicating the presence of fungal elements and diagnosis of a mycosis, then extracted demographic, clinical history, site of infection, stain(s), used and diagnosed mycosis details. Over the 10-year period, 107 cases were found. No apparent increasing and decreasing trend in the number of cases per year or in a period was observed. The age range of affected patients was from 4 to 86 years. Special stains for fungi were only used in 22 of 107 (20.6%) of cases. The most frequently affected site was the sino-nasal area (34%). Mycosis type was determined for 58 (54.2%) cases, comprising aspergillosis (21), candidiasis (14), dermatophytosis (6), mucormycosis (3), two cases each of chromoblastomycosis, histoplasmosis, eumycetoma, entomophthoromycosis, sporotrichosis, and Malassezia infection and a single case each of cryptococcosis and deep onychomycosis. Of the 53 (49.5%) cases with presumptive diagnosis data, only seven (13.2%) had a pre-biopsy suspicion of mycosis. There is a wide spectrum of mycoses in Ghana, including endemic mycoses not previously reported. Improving the use of special fungal stains could increase yield and mycoses identification. Laboratory diagnostic capacity needs enhancement to complement histopathology investigations with serology, culture, and molecular methods.


In Ghana, diagnosis of mycoses is mainly based on histopathology findings. To appreciate the varied mycoses diagnosed, we reviewed the reports of major laboratories from 2012 to 2021 and found 107 cases including endemic, rare, and previously unreported cases with fungal stains unusually used.


Assuntos
Aspergilose , Histoplasmose , Micoses , Humanos , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Gana/epidemiologia , Micoses/patologia , Micoses/veterinária , Aspergilose/veterinária , Histoplasmose/veterinária
18.
BMC Infect Dis ; 24(1): 201, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355443

RESUMO

Histoplasmosis is a fungal infection most frequently seen in immunocompromised patients. It is endemic in Central and South America and in Africa. The infection is usually asymptomatic in a healthy individual. Extrapulmonary dissemination can be seen in immunocompromised hosts. Gastrointestinal manifestations frequently involve the terminal ileum and cecum, mimicking Crohn's disease or malignancy. We describe the case of a 36-year-old healthy man from Cameroon, living in Switzerland for 13 years and without any medical nor surgical history, who presented peritonitis not responding to antibiotics. CT-scan showed bowel obstruction and signs of peritonitis. We opted for an explorative laparoscopy, which was converted to laparotomy with extensive adhesiolysis. Diagnostic of histoplasmosis was confirmed by histology and PCR analysis on biopsy. To our knowledge, this is the first described case of peritonitis as main outcome of a disseminated histoplasmosis involving the peritoneum in an immunocompetent patient.


Assuntos
Doença de Crohn , Histoplasmose , Obstrução Intestinal , Peritonite , Masculino , Humanos , Adulto , Histoplasmose/complicações , Doença de Crohn/complicações , Peritonite/diagnóstico , Peritonite/complicações , Camarões
19.
Multimedia | Recursos Multimídia, MULTIMEDIA-SMS-SP | ID: multimedia-12761

RESUMO

A Série Educativa Fauna Sinantrópica é um informativo elaborado pela Divisão de Vigilância de Zoonoses (DVZ), que pretende orientar o cidadão sobre o manejo adequado relativo aos animais sinantrópicos, em especial aqueles que podem transmitir doenças, causar agravos à saúde do homem ou de outros animais e que estão presentes na nossa cidade. A série destaca ainda a biologia desse grupo de animais como ciclo de vida, formas de reprodução, como vivem e medidas preventivas para se evitar acidentes.


Assuntos
Educação em Saúde , Zoonoses , Quirópteros , Raiva , Histoplasmose
20.
mSphere ; 9(2): e0070423, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38259064

RESUMO

Histoplasma capsulatum is a dimorphic fungal pathogen acquired via inhalation of soil-resident spores. Upon exposure to mammalian body temperatures, these fungal elements transform into yeasts that reside primarily within phagocytes. Macrophages (MΦ) provide a permissive environment for fungal replication until T cell-dependent immunity is engaged. MΦ activated by granulocyte macrophage colony stimulating factor (GM-CSF) induces metallothioneins (MTs) that bind zinc (Zn) and deprive yeast cells of labile Zn, thereby disabling fungal growth. Prior work demonstrated that the zinc transporter, ZRT2, was important for fungal survival in vivo. Hence, we constructed a yeast cell reporter strain that expresses green fluorescent protein (GFP) under control of the ZRT2 zinc-regulated promoter. This reporter accurately responds to a medium devoid of Zn. ZRT2 expression increased in GM-CSF, but not interferon-γ, stimulated MΦ. To examine the in vivo response, we infected mice with a reporter yeast strain and assessed ZRT2 expression at 0, 3, 7, and 14 days post-infection (dpi). ZRT2 expression minimally increased at 3 dpi and peaked at 7 dpi, corresponding with the onset of adaptive immunity. We discovered that the major MΦ populations that restrict Zn from the fungus are interstitial MΦ and exudate MΦ. Neutralizing GM-CSF blunted the control of infection but unexpectedly increased ZRT2 expression. This increase was dependent on another cytokine that activates MΦ to control H. capsulatum replication, M-CSF. These findings illustrate the reporter's ability to sense Zn in vitro and in vivo and correlate ZRT2 expression with GM-CSF and M-CSF activation of MΦ.IMPORTANCEPhagocytes use an arsenal of defenses to control the replication of Histoplasma yeasts, one of which is the limitation of trace metals. On the other hand, H. capsulatum combats metal restriction by upregulating metal importers such as the Zn importer ZRT2. This transporter contributes to H. capsulatum pathogenesis upon activation of adaptive immunity. We constructed a fluorescent ZRT2 transcriptional reporter to probe H. capsulatum Zn sensing during infection and exposed the role for M-CSF activation of macrophages when GM-CSF is absent. These data highlight the ways in which fungal pathogens sense metal deprivation in vivo and reveal the potential of metal-sensing reporters. The work adds a new dimension to study how intracellular pathogens sense and respond to the changing environments of the host.


Assuntos
Histoplasma , Histoplasmose , Camundongos , Animais , Histoplasma/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Histoplasmose/microbiologia , Zinco/metabolismo , Saccharomyces cerevisiae , Mamíferos
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