Infect Immun
December 2024
Dormancy is an adaptation in which cells reduce their metabolism, transcription, and translation to stay alive under stressful conditions, preserving the capacity to reactivate once the environment reverts to favorable conditions. Dormancy and reactivation of () are closely linked to intracellular residency within macrophages. Our previous work showed that murine macrophages rely on the viable but not cultivable (VBNC-a dormancy phenotype) fungus from active , with striking differences in immunometabolic gene expression.
View Article and Find Full Text PDFIntroduction: Cancer is an individual disease and its formation and development are specific to each host. Conventional treatments are ineffective in complex cases, such as metastasis, and have severe adverse side effects. New strategies are needed to address the problem, and the use of immunogenic cell death (ICD) as a trigger or booster of the immune system through the exposure of damage-associated molecular patterns, along with tumor antigens, by cancerous cells is presented as an immunization approach in this work.
View Article and Find Full Text PDFChromoblastomycosis is a fungal chronic disease, which affects humans, especially in cutaneous and subcutaneous tissues. There is no standard treatment for Chromoblastomycosis, and it is a therapeutic challenge, due natural resistance of their causative agents, inadequate response of patients and common cases of relapse. Protocols for determination of antifungal drugs susceptibility are not standardized for chromoblastomycosis agents and endpoint definition is usually based on visual inspection, which depends on the analyst, making it sometimes inaccurate.
View Article and Find Full Text PDFPLoS Pathog
November 2023
Macrophages play a key role in disseminated cryptococcosis, a deadly fungal disease caused by Cryptococcus neoformans. This opportunistic infection can arise following the reactivation of a poorly characterized latent infection attributed to dormant C. neoformans.
View Article and Find Full Text PDFVenom-derived peptides are important sources for the development of new therapeutic molecules, especially due to their broad pharmacological activity. Previously, our research group identified a novel natural peptide, named fraternine, with promising effects for the treatment of Parkinson's disease. In the present paper, we synthesized three peptides bioinspired in fraternine: fra-10, fra-14, and fra-24.
View Article and Find Full Text PDFGermline-encoded pattern recognition receptors, particularly C-type lectin receptors (CLRs), are essential for phagocytes to sense invading fungal cells. Among CLRs, Dectin-2 (encoded by Clec4n) plays a critical role in the antifungal immune response as it recognizes high-mannose polysaccharides on the fungal cell wall, triggering phagocyte functional activities and ultimately determining adaptive responses. Here, we assessed the role of Dectin-2 on the course of primary Paracoccidioides brasiliensis systemic infection in mice with Dectin-2-targeted deletion.
View Article and Find Full Text PDFFront Immunol
October 2023
Idiopathic pulmonary fibrosis (IPF) is a progressive, relentless, and deadly disease. Little is known about its pathogenetic mechanisms; therefore, developing efficient pharmacological therapies is challenging. This work aimed to apply a therapeutic alternative using immunomodulatory peptides in a chronic pulmonary fibrosis murine model.
View Article and Find Full Text PDFJ Fungi (Basel)
February 2023
Chromoblastomycosis (CBM) is a disease caused by several dematiaceous fungi from different genera, and is the most common which has been clinically isolated. Genetic transformation methods have recently been described; however, molecular tools for the functional study of genes have been scarcely reported for those fungi. In this work, we demonstrated that gene deletion and generation of the null mutant by homologous recombination are achievable for by the use of two approaches: use of double-joint PCR for cassette construction, followed by delivery of the split-marker by biolistic transformation.
View Article and Find Full Text PDFMicrobiol Spectr
October 2022
Cryptococcus neoformans is an opportunistic fungal pathogen known for its remarkable ability to infect and subvert phagocytes. This ability provides survival and persistence within the host and relies on phenotypic plasticity. The viable but nonculturable (VBNC) phenotype was recently described in C.
View Article and Find Full Text PDFChromoblastomycosis (CBM) is a chronic cutaneous and subcutaneous mycosis caused by black, dimorphic, and filamentous fungi of the family, such as species of the genus . These fungi can switch between the saprophytic forms (conidia and hyphae) and the pathogenic form, the muriform cells (MCs), which is considered an essential mechanism for fungal virulence. Nearly all types of cells can produce membranous structures formed by a lipid bilayer that communicate extracellularly with other cells, known as "extracellular vesicles" (EVs), which may act as virulence factors, as observed for several species of pathogenic fungi.
View Article and Find Full Text PDFDiets rich in omega-3 or -6 fatty acids will produce different profiles for cell membranes phospholipid constitutions. Omegas 3 and 6 are part of the diet and can modulate the inflammatory profile. We evaluated the effects of the oral absorption of fish oil, when associated with a lipid nanoemulsion in an experimental pulmonary inflammatory model.
View Article and Find Full Text PDFZika virus (ZIKV) is an arbovirus from the Flaviviridae family and Flavivirus genus. Neurological events have been associated with ZIKV-infected individuals, such as Guillain-Barré syndrome, an autoimmune acute neuropathy that causes nerve demyelination and can induce paralysis. With the increase of ZIKV infection incidence in 2015, malformation and microcephaly cases in newborns have grown considerably, which suggested congenital transmission.
View Article and Find Full Text PDFParkinson's disease (PD) is a progressive and chronic neurodegenerative disease of the central nervous system. Early treatment for PD is efficient; however, long-term systemic medication commonly leads to deleterious side-effects. Strategies that enable more selective drug delivery to the brain using smaller dosages, while crossing the complex brain-blood barrier (BBB), are highly desirable to ensure treatment efficacy and decrease/avoid unwanted outcomes.
View Article and Find Full Text PDFJ Photochem Photobiol B
March 2021
Cryptococcus is a globally distributed fungal pathogen that primarily afflicts immunocompromised individuals. The therapeutic options are limited and include mostly amphotericin B or fluconazole, alone or in combination. The extensive usage of antifungals allowed the selection of resistant pathogens posing threats to global public health.
View Article and Find Full Text PDFis an encapsulated yeast that causes disease mainly in immunosuppressed hosts. It is considered a facultative intracellular pathogen because of its capacity to survive and replicate inside phagocytes, especially macrophages. This ability is heavily dependent on various virulence factors, particularly the glucuronoxylomannan (GXM) component of the polysaccharide capsule.
View Article and Find Full Text PDFMost people infected with the fungus spp. do not get sick, but approximately 5% develop paracoccidioidomycosis. Understanding how host immunity determinants influence disease development could lead to novel preventative or therapeutic strategies; hence, we used two mouse strains that are resistant (A/J) or susceptible (B10.
View Article and Find Full Text PDFis a human pathogenic fungus that mainly afflicts immunocompromised patients. One of its virulence strategies is the production of extracellular vesicles (EVs), containing cargo with immunomodulatory properties. We evaluated EV's characteristics produced by capsular and acapsular strains of (B3501 and ΔCap67, respectively) growing in nutritionally poor or rich media and co-cultures with bone marrow-derived macrophages or dendritic cells from C57BL/6 mice.
View Article and Find Full Text PDFPLoS Negl Trop Dis
June 2020
Chromoblastomycosis (CBM) is a chronic worldwide subcutaneous mycosis, caused by several dimorphic, pigmented dematiaceous fungi. It is difficult to treat patients with the disease, mainly because of its recalcitrant nature. The correct activation of host immune response is critical to avoid fungal persistence in the tissue and disease chronification.
View Article and Find Full Text PDFErgosterol is the most important membrane sterol in fungal cells and a component not found in the membranes of human cells. We identified the ERG6 gene in the AIDS-associated fungal pathogen, Cryptococcus neoformans, encoding the sterol C-24 methyltransferase of fungal ergosterol biosynthesis. In this work, we have explored its relationship with high-temperature growth and virulence of C.
View Article and Find Full Text PDFThe cell wall has a critical role in the host immune response to fungal pathogens. In this study, we investigated the influence of two cell wall fractions of the dimorphic fungi (Pb) in the generation of monocyte-derived dendritic cells (MoDCs). Monocytes were purified from the peripheral blood of healthy donors and cultivated for 7 days in medium supplemented with IL-4 and GM-CSF in the presence of Pb cell wall fractions: the alkali-insoluble F1, constituted by β-1,3-glucans, chitin and proteins, and the alkali-soluble F2, mainly constituted by α-glucan.
View Article and Find Full Text PDFAntimicrobial peptides (AMPs) are small molecules with microbicidal and immunoregulatory activities. In this study we evaluated the anti-inflammatory and antimicrobial activities of peptides ToAP3 and ToAP4, AMPs from the venom of the Brazilian scorpion Tityus obscurus. To test the peptides' activity, murine bone marrow-derived macrophages (BMDMs) or dendritic cells (BMDCs) were stimulated with peptides plus LPS to analyze their ability to modulate cytokine release as well as phenotypic markers.
View Article and Find Full Text PDFBackground: Anti-Tumor Necrosis Factor-alpha therapy has become clinically important for treating inflammatory bowel disease. However, the use of conventional immunotherapy requires a systemic exposure of patients and collateral side effects. Lactic acid bacteria have been shown to be effective as mucosal delivering system for cytokine and single domain antibodies, and it is amenable to clinical purposes.
View Article and Find Full Text PDFAbs exert several of their effector functions by binding to cell surface receptors. For murine IgG3 (mIgG3), the identity of its receptors (and the very existence of a receptor) is still under debate, as not all mIgG3 functions can be explained by interaction with FcγRI. This implies the existence of an alternate receptor, whose identity we sought to pinpoint.
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