ABSTRACT
Over the past decade, compelling evidence has unveiled previously overlooked adaptive characteristics of innate immune cells. Beyond their traditional role in providing short, non-specific protection against pathogens, innate immune cells can acquire antigen-agnostic memory, exhibiting increased responsiveness to secondary stimulation. This long-term de-facto innate immune memory, also termed trained immunity, is mediated through extensive metabolic rewiring and epigenetic modifications. While the upregulation of trained immunity proves advantageous in countering immune paralysis, its overactivation contributes to the pathogenesis of autoinflammatory and autoimmune disorders. In this review, we present the latest advancements in the field of innate immune memory followed by a description of the fundamental mechanisms underpinning trained immunity generation and different cell types that mediate it. Furthermore, we explore its implications for various diseases and examine current limitations and its potential therapeutic targeting in immune-related disorders.
Subject(s)
Epigenesis, Genetic , Immunity, Innate , Immunologic Memory , Humans , Animals , Autoimmune Diseases/immunology , Adaptive Immunity , Trained ImmunityABSTRACT
Candida spp. are the fourth leading cause of bloodstream infections in hospitalized patients and the most common cause of invasive fungal infection. No vaccine against Candida spp. or other fungal pathogens of humans is available. We recently discovered the Blastomyces Dectin-2 ligand endoglucanase 2 that harbors antigenic and adjuvant functions and can function as a protective vaccine against that fungus. We also reported that the adjuvant activity, which is mediated by O-mannans decorating the C terminus of Blastomyces Dectin-2 ligand endoglucanase 2, can augment peptide Ag-induced vaccine immunity against heterologous agents, including Cryptococcus, Candida, and influenza. In this article, we report that the O-linked mannans alone, in the absence of any antigenic peptide, can also protect against systemic candidiasis, reducing kidney fungal load and increasing survival in a Dectin-2-dependent manner. We found that this long-term glycan-induced protection is mediated by innate lymphocyte populations including TCR-γδ+ T cells, innate lymphoid cells, and NK cells that subsequently activate and release reactive oxygen species from neutrophils and monocytes. Our findings suggest that Blastomyces O-mannan displayed by Eng2 induces a form of protective trained immunity mediated by innate lymphocyte populations.
ABSTRACT
INTRODUCTION: Untreated gout is characterised by monosodium urate (MSU) crystal accumulation responsible for recurrent flares that are commonly separated by asymptomatic phases. Both phases are inflammatory conditions of variable intensity. Gout flares are self-limited inflammatory reactions involving multiple mediators. This study aimed to characterise the inflammatory profiles of gout at different phases. METHODS: Using the Olink targeted proteomics, levels of 92 inflammation-related proteins were measured in plasma samples of a prospective gout population (GOUTROS), collected at gout flare (T1), the intercritical phase (T2) and after reaching the target serum urate level under urate-lowering therapy (T3). Results were validated in an independent cohort (OLT1177-05) with plasmas collected at T1 and T2. Ex vivo and in vitro experiments were performed to assess the inflammatory properties of new biomarkers. RESULTS: In total, 21 inflammatory new biomarkers were differentially expressed during the three time-points of gout disease. The levels of four of these proteins (interleukin 6 (IL-6), colony-stimulating factor 1, vascular endothelial growth factor A and tumour necrosis factor superfamily 14 (TNFSF14)) were increased during gout flare in an independent cohort. IL-6 and TNFSF14 had the highest fold change in expression during T1 versus T2 or T3. TNFSF14 was produced at the inflamed joint and enhanced the inflammatory response induced by lipopolysaccharide and MSU crystal stimulation. Conversely, TNFSF14 blockade reduced the inflammatory response. Additionally, single nucleotide polymorphisms of TNFSF14 affected the ability of myeloid cells to produce inflammatory cytokines. CONCLUSION: Gout flare involves multiple inflammatory mediators that may be used as potential therapeutic targets.
Subject(s)
Biomarkers , Gout , Tumor Necrosis Factor Ligand Superfamily Member 14 , Humans , Gout/drug therapy , Gout/blood , Biomarkers/blood , Male , Middle Aged , Female , Tumor Necrosis Factor Ligand Superfamily Member 14/blood , Symptom Flare Up , Cytokines/blood , Gout Suppressants/therapeutic use , Aged , Uric Acid/blood , Prospective Studies , Interleukin-6/blood , Adult , Proteomics/methods , Vascular Endothelial Growth Factor A/bloodABSTRACT
OBJECTIVE: We aimed to characterize calcium-containing crystals present in synovial fluid from patients with knee osteoarthritis (OA) using Raman spectroscopy, and specifically investigate the biological effects of calcite crystals. DESIGN: Thirty-two synovial fluid samples were collected pre-operatively from knee OA patients undergoing total joint arthroplasty. An integrated Raman polarized light microscope was used for identification of crystals in synovial fluid. Human peripheral blood mononuclear cells (PBMC's), human OA articular chondrocytes (HACs) and fibroblast-like synoviocytes (FLSs) were exposed to calcite crystals. Expression of relevant cytokines and inflammatory genes were measured using ELISA and real-time PCR. RESULTS: Various calcium-containing crystals were identified, including calcium pyrophosphate (37.5â¯%) and basic calcium phosphate (21.8â¯%), but they were never found simultaneously in the same OA synovial fluid sample. For the first time, we discovered the presence of calcite crystals in 93.8â¯% of the samples, while dolomite was detected in 25â¯% of the cases. Characterization of the cellular response to calcite crystal exposure revealed increased production of innate immune-derived cytokines by PBMC's, when co-stimulated with lipopolysaccharide (LPS). Additionally, calcite crystal stimulation of HACs and FLSs resulted in enhanced secretion of pro-inflammatory molecules and alterations in the expression of extracellular matrix remodeling enzymes. CONCLUSIONS: This study highlights the unique role of Raman spectroscopy in OA crystal research and identified calcite as a novel pro-inflammatory crystal type in OA synovial fluid. Understanding the role of specific crystal species in the OA joint may open new avenues for pharmacological interventions and personalized approaches to treating OA.
ABSTRACT
BACKGROUND: Hyperuricemia has been shown to be an inducer of pro-inflammatory mediators by human primary monocytes. To study the deleterious effects of hyperuricemia, a reliable and stable in vitro model using soluble urate is needed. One recent report showed different urate-dissolving methods resulted in either pro-inflammatory or anti-inflammatory properties. The aim of this study was to compare the effect of two methods of dissolving urate on both primary human peripheral blood mononuclear cells (PBMCs) and THP-1 cells. The two methods tested were 'pre-warming' and 'dissolving with NaOH'. METHODS: Primary human PBMCs and THP-1 cells were exposed to urate solutions, prepared using the two methodologies: pre-warming and dissolving with NaOH. Afterwards, cells were stimulated with various stimuli, followed by the measurement of the inflammatory mediators IL-1ß, IL-6, IL-1Ra, TNF, IL-8, and MCP-1. RESULTS: In PBMCs, we observed an overall pro-inflammatory effect of urate, both in the pre-warming and the NaOH dissolving method. A similar pro-inflammatory effect was seen in THP-1 cells for both dissolving methods after restimulation. However, THP-1 cells exhibited pro-inflammatory profile with exposure to urate alone without restimulation. We did not find MSU crystals in our cellular assays. CONCLUSIONS: Overall, the urate dissolving methods do not have critical impact on its inflammatory properties. Soluble urate prepared using either of the two methods showed mostly pro-inflammatory effects on human primary PBMCs and monocytic cell line THP-1. However, human primary PBMCs and the THP-1 differ in their response to soluble urate without restimulation.
Subject(s)
Hyperuricemia , Uric Acid , Humans , Uric Acid/pharmacology , Uric Acid/metabolism , Hyperuricemia/metabolism , Leukocytes, Mononuclear/metabolism , Sodium Hydroxide/metabolism , Sodium Hydroxide/pharmacology , Monocytes , Inflammation Mediators/metabolismABSTRACT
Cytokines of the interleukin (IL)-1 superfamily including the different IL-36 isoforms, have been reported as mediators of acute and chronic inflammation in human skin diseases, such as psoriasis. Here, we demonstrated for the first time that Sporothrix schenckii and S. brasiliensis, the fungi that cause subcutaneous infection sporotrichosis, can induce the expression of IL-36α, IL-36γ and IL-36Ra in human keratinocytes and primary peripheral blood mononuclear cells (PBMCs). Specifically, IL-36γ was differentially expressed by keratinocytes stimulated with Sporothrix yeasts when compared to the commensal microorganism Staphylococcus epidermidis. The exposure of keratinocytes to 24 h or 7-days culture supernatant of PBMCs stimulated with Sporothrix induced higher IL-36γ production compared to direct stimulation of keratinocytes with the live fungus. We identified that IL-36γ mRNA expression in keratinocytes is increased in the presence of IL-17, TNF, IL-1ß and IL-1α and these cytokines may act synergistically to maintain IL-36γ production. Lastly, using a cohort of 164 healthy individuals, we showed that individuals carrying variants of the IL36G gene (rs11690399 and rs11683399) exhibit increased IL-36γ production as well as increased innate cytokine production after Sporothrix exposure. Importantly, stimulation of PBMCs with recombinant IL-36γ increased the production of IL-1ß and IL-6, while IL-36Ra were able to decrease the concentration of these cytokines. Our findings contribute to the understanding of the pathogenesis of sporotrichosis and suggest that IL-36γ may be involved in maintaining the cytokine loop that leads to tissue destruction by exacerbating the immune response in sporotrichosis. Of high interest, we present the IL-36 signalling pathway as a potential new therapeutic target.
Subject(s)
Sporothrix , Sporotrichosis , Humans , Cytokines/metabolism , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Interleukins/genetics , Interleukins/metabolism , Keratinocytes , Leukocytes, Mononuclear , Sporothrix/geneticsABSTRACT
Fungal skin infections are distributed worldwide and can be associated with economic and social traits. The immune response related to skin cells is complex and its understanding is essential to the comprehension of each cell's role and the discovery of treatment alternatives. The first studies of trained immunity (TI) described the ability of monocytes, macrophages and natural killer (NK) cells to develop a memory-like response. However, the duration of TI does not reflect the shorter lifespan of these cells. These conclusions supported later studies showing that TI can be observed in stem and haematopoietic cells and, more recently, also in non-immune skin cells such as fibroblasts, highlighting the importance of resident cells in response to skin disorders. Besides, the participation of less studied proinflammatory cytokines in the skin immune response, such as IL-36γ, shed light into a new possibility of inflammatory pathway blockade by drugs. In this review, we will discuss the skin immune response associated with fungal infections, the role of TI in skin and clinical evidence supporting opportunities and challenges of TI and other inflammatory responses in the pathogenesis of fungal skin infections.
Subject(s)
Mycoses , Trained Immunity , Humans , Immunity, Innate , Macrophages , MonocytesABSTRACT
OBJECTIVE: Basic calcium phosphate (BCP) crystals can activate the NLRP3 inflammasome and are potentially involved in the pathogenesis of osteoarthritis (OA). In order to elucidate relevant inflammatory mechanisms in OA, we used a functional genomics approach to assess genetic variation influencing BCP crystal-induced cytokine production. METHOD: Peripheral blood mononuclear cells (PBMCs) were isolated from healthy volunteers who were previously genotyped and stimulated with BCP crystals and/or lipopolysaccharide (LPS) after which cytokines release was assessed. Cytokine quantitative trait locus (cQTL) mapping was performed. For in vitro validation of the cQTL located in anoctamin 3 (ANO3), PBMCs were incubated with Tamoxifen and Benzbromarone prior to stimulation. Additionally, we performed co-localisation analysis of our top cQTLs with the most recent OA meta-analysis of genome-wide association studies (GWAS). RESULTS: We observed that BCP crystals and LPS synergistically induce IL-1ß in human PBMCs. cQTL analysis revealed several suggestive loci influencing cytokine release upon stimulation, among which are quantitative trait locus annotated to ANO3 and GLIS3. As functional validation, anoctamin inhibitors reduced IL-1ß release in PBMCs after stimulation. Co-localisation analysis showed that the GLIS3 locus was shared between LPS/BCP crystal-induced IL-1ß and genetic association with Knee OA. CONCLUSIONS: We identified and functionally validated a new locus, ANO3, associated with LPS/BCP crystal-induced inflammation in PBMCs. Moreover, the cQTL in the GLIS3 locus co-localises with the previously found locus associated with Knee OA, suggesting that this Knee OA locus might be explained through an inflammatory mechanism. These results form a basis for further exploration of inflammatory mechanisms in OA.
Subject(s)
Osteoarthritis, Knee , Quantitative Trait Loci , Humans , Toll-Like Receptor 4/genetics , Leukocytes, Mononuclear , Genome-Wide Association Study , Lipopolysaccharides , Calcium Phosphates/pharmacology , Inflammation/genetics , Genomics , AnoctaminsABSTRACT
Previous studies have shown that monocytes can be 'trained' or tolerized by certain stimuli to respond stronger or weaker to a secondary stimulation. Rewiring of glucose metabolism was found to be important in inducing this phenotype. As we previously found that Borrelia burgdorferi (B. burgdorferi), the causative agent of Lyme borreliosis (LB), alters glucose metabolism in monocytes, we hypothesized that this may also induce long-term changes in innate immune responses. We found that exposure to B. burgdorferi decreased cytokine production in response to the TLR4-ligand lipopolysaccharide (LPS). In addition, B. burgdorferi exposure decreased baseline levels of glycolysis, as assessed by lactate production. Using GWAS analysis, we identified a gene, microfibril-associated protein 3-like (MFAP3L) as a factor influencing lactate production after B. burgdorferi exposure. Validation experiments proved that MFAP3L affects lactate- and cytokine production following B. burgdorferi stimulation. This is mediated by functions of MFAP3L, which includes activating ERK2 and through activation of platelet degranulation. Moreover, we showed that platelets and platelet-derived factors play important roles in B. burgdorferi-induced cytokine production. Certain platelet-derived factors, such chemokine C-X-C motif ligand 7 (CXCL7) and (C-C motif) ligand 5 (CCL5), were elevated in the circulation of LB patients in comparison to healthy individuals.
Subject(s)
Lipopolysaccharides , Lyme Disease , Humans , Ligands , Toll-Like Receptor 4 , Chemokines/metabolism , Glucose , LactatesABSTRACT
Sporotrichosis is a deep mycosis caused by dimorphic species of the genus Sporothrix, with differences in pathogenicity between S. schenckii and S. brasiliensis species. Recently, it was discovered that the cell wall peptidorhamnomannan (PRM) from S. brasiliensis has additional unknown rhamnose residues. We hypothesize that the structural differences of Sporothrix spp PRMs impact the host's immune response and may explain the severity of sporotrichosis caused by S. brasiliensis. We demonstrate that S. brasiliensis yeasts and its PRM (S.b PRM) induced a strong inflammatory response in human PBMCs, with high production of TNF-α, IL-6 and IL-1ß and induction of T-helper cytokines IFN-γ, IL-17 and IL-22. In contrast, S. schenckii yeasts and its PRM induced higher concentrations of interleukin-1 receptor antagonist (IL-1Ra), which resulted in low production of T-helper cytokines such as IL-17 and IL-22. CR3 and dectin-1 were required for cytokine induction by both PRMs, while TLR2 and TLR4 were required for the response of S.s PRM and S.b PRM, respectively. IL-1ß and IL-1α production induced by S. brasiliensis yeasts and S.b PRM were dependent on inflammasome and caspase-1 activation. S. schenckii and S.s PRM were able to induce IL-1ß independent of ROS. In conclusion, these findings improve our understanding of the pathogenesis of Sporothrix spp. by reporting differences of immunological responses induced by S. schenckii and S. brasiliensis. The study also opens the gateway for novel treatment strategies targeting local inflammation and tissue destruction induced by S. brasiliensis infection through IL-1 inhibition.
Subject(s)
Sporothrix , Sporotrichosis , Cytokines , Glycoproteins , Humans , Interleukin-17 , Sporotrichosis/pathologyABSTRACT
A biofilm is represented by a community of microorganisms capable of adhering to a surface and producing substances that envelop the cells, forming an extracellular matrix. The extracellular matrix is responsible for protecting microorganisms against environmental stress, hosts the immune system and confers resistance to antimicrobials. Fusarium keratoplasticum is a common species of FSSC (Fusarium solani species complex) associated with human infections, being the most prevalent species related to biofilm formation in hospital water systems and internal pipelines. With this in mind, this study aimed to characterise the biofilm formed by the fungus F. keratoplasticum and to evaluate the effects of farnesol, a fungal quorum sensing (QS) molecule, on the preformed biofilm and also during its formation at different times (adhesion and 24, 48 and 72 h). F. keratoplasticum is able to adhere to an abiotic surface and form a dense biofilm in 72 h, with increased total biomass and matrix modulation with the presence of extracellular DNA, RNA, polysaccharides and proteins. Farnesol exhibited important anti-biofilm activity, causing the destruction of hyphae and the extracellular matrix in preformed biofilm and preventing the adhesion of conidia, filamentation and the formation of biofilm. Few studies have characterised the formation of biofilm by filamentous fungi. Our findings suggest that farnesol acts efficiently on F. keratoplasticum biofilm since this molecule is capable of breaking the extracellular matrix, thereby disarranging the biofilm.
Subject(s)
Antifungal Agents/pharmacology , Biofilms/drug effects , Farnesol/pharmacology , Fusarium/drug effects , Animals , Chlorocebus aethiops , HeLa Cells , Humans , Hyphae/drug effects , Quorum Sensing/drug effects , Spores, Fungal/drug effects , Vero CellsABSTRACT
Fusariosis is an infection that is caused by fungi of the Fusarium genus. It is the second most common fungus that is associated with human fungal infections, usually in immunocompromised individuals. The incidence of such infections has been increasing, including in immunocompetent hosts. Studies of host-pathogen interactions are scarce, and the pathophysiology of the disease is unknown. One limitation of such studies is the lack of adequate techniques for mammalian infection, in which no standardized protocols have been established with fungi with a focus on the respiratory tract. The aim of the present study was to assess the first 24â¯h of infection after the intratracheal inoculation of F. solani microconidia in immunocompetent mice. Colony-forming units (CFU) were counted, and histopathological analysis was performed. Under conditions of high fungal burden, F. solani caused lethal tissue damage in the lungs. Under conditions of low fungal burden, the infection was not lethal, but several alterations of pulmonary tissue and the presence of the fungus in the lungs were observed. No evidence of fungal dissemination was found in the kidneys, spleen, liver, or heart 24â¯h after infection. The present intratracheal model effectively established fungal infection and appears to be suitable for studies of Fusarium spp.
Subject(s)
Fusariosis/microbiology , Fusariosis/pathology , Fusarium/pathogenicity , Immunocompromised Host , Trachea/microbiology , Trachea/pathology , Animals , Colony Count, Microbial , Disease Models, Animal , Female , Fusarium/growth & development , Host-Pathogen Interactions/drug effects , Host-Pathogen Interactions/immunology , Immunosuppressive Agents/adverse effects , Mice , Mice, Inbred BALB C , Mycoses/immunology , Mycoses/pathology , Spores, Fungal , Survival Rate , Trachea/drug effectsABSTRACT
Candida albicans cell wall component ß-glucan has been extensively studied for its ability to induce epigenetic and functional reprogramming of innate immune cells, a process termed trained immunity. We show that a high-complexity blend of two individual ß-glucans from Saccharomyces cerevisiae possesses strong bioactivity, resulting in an enhanced trained innate immune response by human primary monocytes. The training required the Dectin-1/CR3, TLR4, and MMR receptors, as well as the Raf-1, Syk, and PI3K downstream signaling molecules. By activating multiple receptors and downstream signaling pathways, the components of this ß-glucan preparation are able to act synergistically, causing a robust secondary response upon an unrelated challenge. In in-vivo murine models of melanoma and bladder cell carcinoma, pre-treatment of mice with the ß-glucan preparation led to a significant reduction in tumor growth. These insights may aid in the development of future therapies based on ß-glucan structures that induce an effective trained immunity response.
Subject(s)
Saccharomyces cerevisiae , beta-Glucans , Humans , Animals , Mice , Trained Immunity , beta-Glucans/pharmacology , Monocytes , Signal TransductionABSTRACT
Paracoccidioidomycosis (PCM) is a systemic mycosis caused by fungi of the genus Paracoccidioides and the different clinical forms of the disease are associated with the host immune responses. Quantitative trait loci mapping analysis was performed to assess genetic variants associated with mononuclear-cells-derived cytokines induced by P. brasiliensis on 158 individuals. We identified the rs11053595 SNP, which is present in the CLEC7A gene (encodes the Dectin-1 receptor) and the rs62290169 SNP located in the PROM1 gene (encodes CD133) associated with the production of IL-1ß and IL-22, respectively. Functionally, the blockade of the dectin-1 receptor abolished the IL-1ß production in P. brasiliensis-stimulated PBMCs. Moreover, the rs62290169-GG genotype was associated with higher frequency of CD38+ Th1 cells in PBMCs cultured with P. brasiliensis yeasts. Therefore, our research indicates that the CLEC7A and PROM1 genes are important for the cytokine response induced by P. brasiliensis and may influence the Paracoccidioidomycosis disease outcome.
ABSTRACT
Monoclonal antibodies (mAbs) are promising alternatives to treat infectious diseases, especially given their potential for applications in combination therapies with antimicrobial drugs to enhance the antifungal efficacy. Protection mediated by mAbs used to treat experimental paracoccidioidomycosis (PCM) has been demonstrated previously. Our aim in the present work was to characterize a monoclonal antibody (mAbF1.4) raised against a cell wall glycoconjugate fraction of Paracoccidioides spp. and to analyze its efficacy combined with trimethoprim-sulfamethoxazole (TMP/SMX) as treatment for experimental PCM. We demonstrated that the epitope recognized by mAbF1.4 is consistent with branched glucose residues present on a cell wall ß-glucan polymer. In vitro, mAbF1.4 increased the phagocytic capacity and nitric oxide concentration induced by the macrophage cell line J774.1A, and this resulted in a significant reduction in the viability of the opsonophagocytized yeasts. In vivo, we detected a significant reduction in pulmonary fungal burdens of mice treated with mAbF1.4 in association with TMP/SMX, which correlated with increased pulmonary concentrations (determined by ELISA) of IFN- γ, TNF-α, IL-10 and IL-17. In parallel, we observed a decrease in IL-4, suggesting that the treatment was associated with a mixed Th1-Th17 type immune response. Histopathology of lung segments from mice receiving the combination therapy showed a significant reduction in granulomas, which were well-defined, and improved maintenance of lung architecture. These findings demonstrate that mAbF1.4 + TMP/SMX therapy is a promising approach to combat PCM as well as decrease disease sequelae and highlights the potential benefits of immune mediators in PCM combined immunotherapy.
Subject(s)
Antibodies, Monoclonal/pharmacology , Immunotherapy/methods , Paracoccidioides/immunology , Paracoccidioidomycosis/immunology , Trimethoprim, Sulfamethoxazole Drug Combination/pharmacology , Animals , Antifungal Agents/pharmacology , Antigens, Fungal/immunology , Cytokines/immunology , Disease Models, Animal , Female , Lung/microbiology , Lung/pathology , Macrophages/immunology , Male , Mice , Mice, Inbred C57BL , Paracoccidioidomycosis/drug therapy , Paracoccidioidomycosis/microbiologyABSTRACT
As there are more than 6 million human deaths due to mycoses each year, there is an urgent need to develop fungal vaccines. Moreover, given the similarities among pathogenic fungi, it may be possible to create a multi-fungi vaccine. In this study, we combined immunoproteomic and immunopeptidomic methods, for which we have adapted a technique based on co-immunoprecipitation (Co-IP) that made it possible to map Histoplasma capsulatum epitopes for the first time in a natural context using murine dendritic cells (DCs) and macrophages (Mφ). Although polysaccharide epitopes exist, this research focused on mapping protein epitopes as these are more immunogenic. We used different algorithms to screen proteins and peptides identified by two-dimensional electrophoresis (2-D) and Co-IP. Seventeen proteins were revealed by 2-D gels, and 45 and 24 peptides from distinct proteins were presented by DCs and Mφ, respectively. We then determined which epitopes were restricted to MHC-I and II from humans and mice and showed high promiscuity, but lacked identity with human proteins. The 4 most promising peptides were synthesized, and the peptides with and without incorporation into glucan particles induced CD4+ and CD8+ T cell proliferation and produced a Th1 and Th17 response marked by the secretion of high levels of IFN-γ, IL-17 and IL-2. These epitopes were from heat shock protein 60, enolase, and the ATP-dependent molecular chaperone HSC82, and they each have a high degree of identity with proteins expressed by other medically important pathogenic fungi. Thus, the epitopes described in this study have the potential for use in the development of vaccines that could result in cross-protection among fungal species.
Subject(s)
Fungal Vaccines/immunology , Histoplasma/immunology , Peptidomimetics , Proteomics , Animals , Epitope Mapping , Male , Mice , Mice, Inbred C57BLABSTRACT
Acrocomia totai Mart (Arecaceae) is a palm tree native to South America, widely studied for biodiesel production. The aim of this work was to perform the first phytochemical study of A. totai leaves, as well as to do biological assays against human cancer cell lines. A new triterpene of the hopane class named totaiol (1), three known triterpenes (2-4), and two phytosteroids (5-6) were identified. The new natural product was characterized using 1 D and 2 D NMR, single crystal X-ray diffraction analises, and high resolution mass spectrometry. The intercontacts in the crystal packing were also analised. Complete stereochemical characterization of compound 1 revealed an unusual positioning pattern for methyl and isopropenyl groups in the polycyclic skeleton. Compounds 1-5 were evaluated for the first time in antiproliferative assays against Ca Ski, MCF-7 and MCF-10 cells. The new natural product was active against Ca Ski cells with IC50 ≤ 6.25 µg mL-1.
Subject(s)
Arecaceae , Triterpenes , Humans , Phytochemicals , Plant Leaves , Trees , Triterpenes/pharmacologyABSTRACT
Aim: Elucidate the antifungal efficacy of biologically synthesized silver nanoparticles with ethanolic propolis extract (AgNPs PE) against the planktonic forms and biofilms of clinically important fungi. Materials & methods: AgNPs were synthesized, characterized and evaluated for cytotoxicity, mutagenicity and antimicrobial activity. Results: AgNPs PE displayed a colloidal appearance, good stability and size of 2.0-40.0 nm. AgNPs PE demonstrated lower cytotoxicity and nonmutagenic potential. In addition, AgNPs PE displayed antifungal properties against all tested isolates, inhibiting growth at concentrations lower than the cytotoxic effect. Mature biofilms treated for 48 h with AgNPs PE showed significant reduction of viable cells, metabolic activity and total biomass. Conclusion: This is the first time that AgNPs have been synthesized from an ethanolic extract of propolis only, proving antifungal, antibiofilm, atoxic and nonmutagenic properties.
Subject(s)
Antifungal Agents/toxicity , Metal Nanoparticles/toxicity , Mycoses/microbiology , Propolis/chemistry , Silver/toxicity , Antifungal Agents/chemistry , Biofilms/drug effects , Candida/drug effects , Candida/physiology , Fusarium/drug effects , Fusarium/physiology , Humans , Metal Nanoparticles/chemistry , Microbial Sensitivity Tests , Mycoses/drug therapy , Silver/chemistryABSTRACT
Treatment modalities for systemic mycoses are still limited. Currently, the main antifungal therapeutics include polyenes, azoles, and echinocandins. However, even in the setting of appropriate administration of antifungals, mortality rates remain unacceptably high. Moreover, antifungal therapy is expensive, treatment periods can range from weeks to years, and toxicity is also a serious concern. In recent years, the increased number of immunocompromised individuals has contributed to the high global incidence of systemic fungal infections. Given the high morbidity and mortality rates, the complexity of treatment strategies, drug toxicity, and the worldwide burden of disease, there is a need for new and efficient therapeutic means to combat invasive mycoses. One promising avenue that is actively being pursued is nanotechnology, to develop new antifungal therapies and efficient vaccines, since it allows for a targeted delivery of drugs and antigens, which can reduce toxicity and treatment costs. The goal of this review is to discuss studies using nanoparticles to develop new therapeutic options, including vaccination methods, to combat systemic mycoses caused by Candida sp., Cryptococcus sp., Paracoccidioides sp., Histoplasma sp., Coccidioides sp., and Aspergillus sp., in addition to providing important information on the use of different types of nanoparticles, nanocarriers and their corresponding mechanisms of action.
Subject(s)
Mycoses , Nanoparticles , Vaccines , Antifungal Agents/therapeutic use , Echinocandins , Humans , Mycoses/drug therapy , Mycoses/prevention & controlABSTRACT
: The increasing incidence in systemic fungal infections in humans has increased focus for the development of fungal vaccines and use of monoclonal antibodies. Invasive mycoses are generally difficult to treat, as most occur in vulnerable individuals, with compromised innate and adaptive immune responses. Mortality rates in the setting of our current antifungal drugs remain excessively high. Moreover, systemic mycoses require prolonged durations of antifungal treatment and side effects frequently occur, particularly drug-induced liver and/or kidney injury. The use of monoclonal antibodies with or without concomitant administration of antifungal drugs emerges as a potentially efficient treatment modality to improve outcomes and reduce chemotherapy toxicities. In this review, we focus on the use of monoclonal antibodies with experimental evidence on the reduction of fungal burden and prolongation of survival in in vivo disease models. Presently, there are no licensed monoclonal antibodies for use in the treatment of systemic mycoses, although the potential of such a vaccine is very high as indicated by the substantial promising results from several experimental models.