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Bo Y, Lu Q, Li B, Sha R, Yu H, Miao C. The role of platelets in central hubs of inflammation: A literature review. Medicine (Baltimore) 2024; 103:e38115. [PMID: 38728509 PMCID: PMC11081549 DOI: 10.1097/md.0000000000038115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 04/12/2024] [Indexed: 05/12/2024] Open
Abstract
Platelets are increasingly recognized for their multifaceted roles in inflammation beyond their traditional involvement in haemostasis. This review consolidates knowledge on platelets as critical players in inflammatory responses. This study did an extensive search of electronic databases and identified studies on platelets in inflammation, focusing on molecular mechanisms, cell interactions, and clinical implications, emphasizing recent publications. Platelets contribute to inflammation via surface receptors, release of mediators, and participation in neutrophil extracellular trap formation. They are implicated in diseases like atherosclerosis, rheumatoid arthritis, and sepsis, highlighting their interaction with immune cells as pivotal in the onset and resolution of inflammation. Platelets are central to regulating inflammation, offering new therapeutic targets for inflammatory diseases. Future research should explore specific molecular pathways of platelets in inflammation for therapeutic intervention.
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Affiliation(s)
- Yan Bo
- College of Medicine, Northwest Minzu University, Lanzhou, China
| | - Qingyang Lu
- School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR of China
| | - Beilei Li
- Department of Rehabilitation Medicine, Shanghai Xuhui Central Hospital, Shanghai, China
| | - Ren Sha
- School of Economics and Management, Henan Polytechnic University, Jiaozuo, China
| | - Haodong Yu
- School of Economic Crime Investigation, Jiangxi Police Academy, Nanchang, China
| | - Chuhan Miao
- School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR of China
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2
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The Antidepressant Sertraline Affects Cell Signaling and Metabolism in Trichophyton rubrum. J Fungi (Basel) 2023; 9:jof9020275. [PMID: 36836389 PMCID: PMC9961077 DOI: 10.3390/jof9020275] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/24/2023] [Accepted: 02/08/2023] [Indexed: 02/22/2023] Open
Abstract
The dermatophyte Trichophyton rubrum is responsible for most human cutaneous infections. Its treatment is complex, mainly because there are only a few structural classes of fungal inhibitors. Therefore, new strategies addressing these problems are essential. The development of new drugs is time-consuming and expensive. The repositioning of drugs already used in medical practice has emerged as an alternative to discovering new drugs. The antidepressant sertraline (SRT) kills several important fungal pathogens. Accordingly, we investigated the inhibitory mechanism of SRT in T. rubrum to broaden the knowledge of its impact on eukaryotic microorganisms and to assess its potential for future use in dermatophytosis treatments. We performed next-generation sequencing (RNA-seq) to identify the genes responding to SRT at the transcript level. We identified that a major effect of SRT was to alter expression for genes involved in maintaining fungal cell wall and plasma membrane stability, including ergosterol biosynthetic genes. SRT also altered the expression of genes encoding enzymes related to fungal energy metabolism, cellular detoxification, and defense against oxidative stress. Our findings provide insights into a specific molecular network interaction that maintains metabolic stability and is perturbed by SRT, showing potential targets for its strategic use in dermatophytosis.
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Indications that the Antimycotic Drug Amphotericin B Enhances the Impact of Platelets on Aspergillus. Antimicrob Agents Chemother 2022; 66:e0068122. [PMID: 36190233 PMCID: PMC9578436 DOI: 10.1128/aac.00681-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Platelets are currently thought to harbor antimicrobial functions and might therefore play a crucial role in infections, e.g., those caused by Aspergillus or mucormycetes. The incidence of invasive fungal infections is increasing, particularly during the coronavirus disease 2019 (COVID-19) pandemic, and such infections continue to be life-threatening in immunocompromised patients. For this reason, the interaction of antimycotics with platelets is a key issue to evaluate modern therapeutic regimens. Amphotericin B (AmB) is widely used for the therapy of invasive fungal infections either as deoxycholate (AmB-D) or as a liposomal formulation (L-AmB). We showed that AmB strongly activates platelets within a few minutes. AmB concentrations commonly measured in the blood of patients were sufficient to stimulate platelets, indicating that this effect is highly relevant in vivo. The stimulating effect was corroborated by a broad spectrum of platelet activation parameters, including degranulation, aggregation, budding of microparticles, morphological changes, and enhanced adherence to fungal hyphae. Comparison between the deoxycholate and the liposomal formulation excluded the possibility that the liposomal part of L-Amb is responsible for these effects, as no difference was visible. The induction of platelet activation and alteration by L-AmB resulted in the activation of other parts of innate immunity, such as stimulation of the complement cascade and interaction with granulocytes. These mechanisms might substantially fuel the antifungal immune reaction in invasive mycoses. On the other hand, thrombosis and excessive inflammatory processes might occur via these mechanisms. Furthermore, the viability of L-AmB-activated platelets was consequently decreased, a process that might contribute to thrombocytopenia in patients.
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Negri S, Commisso M, Avesani L, Guzzo F. The case of tryptamine and serotonin in plants: a mysterious precursor for an illustrious metabolite. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:5336-5355. [PMID: 34009335 DOI: 10.1093/jxb/erab220] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/13/2021] [Indexed: 06/12/2023]
Abstract
Indolamines are tryptophan-derived specialized metabolites belonging to the huge and ubiquitous indole alkaloids group. Serotonin and melatonin are the best-characterized members of this family, given their many hormonal and physiological roles in animals. Following their discovery in plants, the study of plant indolamines has flourished and their involvement in important processes, including stress responses, growth and development, and reproduction, has been proposed, leading to their classification as a new category of phytohormones. However, the complex indolamine puzzle is far from resolved, particularly the biological roles of tryptamine, the early serotonin precursor representing the central hub of many downstream indole alkaloids. Tryptophan decarboxylase, which catalyzes the synthesis of tryptamine, strictly regulates the flux of carbon and nitrogen from the tryptophan pool into the indolamine pathway. Furthermore, tryptamine accumulates to high levels in the reproductive organs of many plant species and therefore cannot be classed as a mere intermediate but rather as an end product with potentially important functions in fruits and seeds. This review summarizes current knowledge on the role of tryptamine and its close relative serotonin, emphasizing the need for a clear understanding of the functions of, and mutual relations between, these indolamines and their biosynthesis pathways in plants.
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Affiliation(s)
- Stefano Negri
- Department of Biotechnology, University of Verona, Strada Le Grazie, Verona, Italy
| | - Mauro Commisso
- Department of Biotechnology, University of Verona, Strada Le Grazie, Verona, Italy
| | - Linda Avesani
- Department of Biotechnology, University of Verona, Strada Le Grazie, Verona, Italy
| | - Flavia Guzzo
- Department of Biotechnology, University of Verona, Strada Le Grazie, Verona, Italy
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5
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Dysregulation of Key Proteinases in Aspergillus fumigatus Induced by Blood Platelets. Rep Biochem Mol Biol 2021; 10:95-104. [PMID: 34277873 DOI: 10.52547/rbmb.10.1.95] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 12/13/2020] [Indexed: 11/18/2022]
Abstract
Background Aspergillus fumigatus is the most common species causing invasive aspergillosis (IA), a life-threatening infection with more than 80% mortality. Interactions between A. fumigatus and human blood platelets lead to intravascular thrombosis and localized infarcts. To better understand A. fumigatus pathogenesis, we aimed to analyze the genetic basis of interactions between the pathogen and blood platelets. Methods A bioinformatic pipeline on microarray gene expression dataset, including analysis of differentially expressed genes (DEGs) using Limma R package and their molecular function, as well as biological pathways identification, was conducted to find the effective genes involved in IA. In the wet phase, the gene expression patterns following fungal exposure to blood platelets at 15, 30, 60, and 180 min were evaluated by quantitative reverse transcriptase-PCR analysis. Results Three genes encoding aspartic endopeptidases including (Pep1), (Asp f 13), and (β-glucanase) were the standing candidates. The invasion-promoting fungal proteinase-encoding genes were down-regulated after 30 min of hyphal incubation with blood platelets, and then up-regulated at 60 and 180 min, although only Pep1 was greater than the control at the 60and 180 min time points. Also, the same genes were downregulated in more the clinical isolates relative to the standard strain CBS 144.89. Conclusion Our findings delineate the possible induction of fungal-encoded proteinases by blood platelets. This provides a new research line into A. fumigatus' molecular pathogenesis. Such insight into IA pathogenesis might also guide researchers toward novel platelet-based therapies that involve molecular interventions, especially in IA patients.
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Danilovich ME, Alberto MR, Juárez Tomás MS. Microbial production of beneficial indoleamines (serotonin and melatonin) with potential application to biotechnological products for human health. J Appl Microbiol 2021; 131:1668-1682. [PMID: 33484616 DOI: 10.1111/jam.15012] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/08/2021] [Accepted: 01/19/2021] [Indexed: 12/20/2022]
Abstract
Micro-organisms have showed the ability to produce biologically active compounds associated with neurotransmission in higher organisms. In particular, serotonin- and melatonin-producing microbes are valuable sources for the development of eco-friendly bioproducts. Serotonin and melatonin are indoleamines that have received special attention due to their positive effects on human health. These biomolecules exert a critical role in several physiological or pathological processes, including some mental and neurological disorders. This article includes a review of the microbial production of serotonin and melatonin, their functions in micro-organisms and their potential uses as therapeutic and/or preventive agents to improve human health. A description of the quantification methods employed to detect indoleamines and the evidence found concerning their microbial production at laboratory and industrial scale-for application in biotechnological products-is also provided. The microbial ability to synthesize beneficial indoleamines should be further studied and harnessed, to allow the development of sustainable bioprocesses to produce foods and pharmaceuticals for human health.
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Affiliation(s)
- M E Danilovich
- Instituto de Biotecnología Farmacéutica y Alimentaria (INBIOFAL)-CONICET, Tucumán, Argentina
| | - M R Alberto
- Instituto de Biotecnología Farmacéutica y Alimentaria (INBIOFAL)-CONICET, Tucumán, Argentina
| | - M S Juárez Tomás
- Planta Piloto de Procesos Industriales Microbiológicos (PROIMI)-CONICET, Tucumán, Argentina
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Hou J, Li YQ, Wang ZS, Sun GJ, Mo HZ. Applicative effect of glycinin basic polypeptide in fresh wet noodles and antifungal characteristics. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2017.05.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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8
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Speth C, Rambach G, Würzner R, Lass-Flörl C, Kozarcanin H, Hamad OA, Nilsson B, Ekdahl KN. Complement and platelets: Mutual interference in the immune network. Mol Immunol 2015; 67:108-18. [DOI: 10.1016/j.molimm.2015.03.244] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 03/16/2015] [Accepted: 03/16/2015] [Indexed: 11/28/2022]
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Margalit A, Kavanagh K. The innate immune response to Aspergillus fumigatus at the alveolar surface. FEMS Microbiol Rev 2015; 39:670-87. [PMID: 25934117 DOI: 10.1093/femsre/fuv018] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2015] [Indexed: 01/22/2023] Open
Abstract
Aspergillus fumigatus is an ubiquitous, saprophytic mould that forms and releases airborne conidia which are inhaled by humans on a daily basis. When the immune system is compromised (e.g. immunosuppressive therapy prior to organ transplantation) or there is pre-existing pulmonary malfunction (e.g. asthma, cystic fibrosis, TB lesions), A. fumigatus exploits weaknesses in the host defenses which can result in the development of saphrophytic, allergic or invasive aspergillosis. If not effectively eliminated by the innate immune response, conidia germinate and form invasive hyphae which can penetrate pulmonary tissues. The innate immune response to A. fumigatus is stage-specific and various components of the host's defenses are recruited to challenge the different cellular forms of the pathogen. In immunocompetent hosts, anatomical barriers (e.g. the mucociliary elevator) and professional phagocytes such as alveolar macrophages (AM) and neutrophils prevent the development of aspergillosis by inhibiting the growth of conidia and hyphae. The recognition of inhaled conidia by AM leads to the intracellular degradation of the spores and the secretion of proinflammatory mediators which recruit neutrophils to assist in fungal clearance. During the later stages of infection, dendritic cells activate a protective A. fumigatus-specific adaptive immune response which is driven by Th1 CD4(+) T cells.
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Affiliation(s)
- Anatte Margalit
- Department of Biology, Maynooth University, Co. Kildare, Ireland
| | - Kevin Kavanagh
- Department of Biology, Maynooth University, Co. Kildare, Ireland
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Perkhofer S, Zenzmaier C, Frealle E, Blatzer M, Hackl H, Sartori B, Lass-Flörl C. Differential gene expression in Aspergillus fumigatus induced by human platelets in vitro. Int J Med Microbiol 2015; 305:327-38. [PMID: 25661519 PMCID: PMC4415150 DOI: 10.1016/j.ijmm.2015.01.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 12/10/2014] [Accepted: 01/11/2015] [Indexed: 12/19/2022] Open
Abstract
Invasive aspergillosis is characterized by vascular invasion and thrombosis. In order to determine the antifungal activity of human platelets, hyphal elongation and metabolic activity of a clinical A. fumigatus isolate were measured. Genome-wide identification of differentially expressed genes in A. fumigatus was performed after exposure to platelets for 15, 30, 60 and 180 min. Data were analyzed by gene ontology annotation as well as functional categories (FunCat) and KEGG enrichment analyses. Platelets attenuated hyphal elongation and viability of A. fumigatus and in total 584 differentially expressed genes were identified, many of which were associated with regulation of biological processes, stress response, transport and metabolism. FunCat and KEGG enrichment analyses showed stress response and metabolic adaptation to be increased in response to platelets. Our findings demonstrate that A. fumigatus displayed a specific transcriptional response when exposed to platelets, thus reflecting their antifungal activities.
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Affiliation(s)
- Susanne Perkhofer
- University of Applied Sciences Tyrol, 6020 Innsbruck, Austria; Division of Hygiene and Medical Microbiology, Innsbruck Medical University, 6020 Innsbruck, Austria.
| | | | - Emilie Frealle
- Center for Infection and Immunity of Lille (CIIL), Institut Pasteur de Lille, Biology and Diversity of Emerging Eukaryotic Pathogens (BDEEP), INSERM U1019, CNRS UMR 8204, Univ. Lille Nord de France, Lille, France
| | - Michael Blatzer
- Division of Hygiene and Medical Microbiology, Innsbruck Medical University, 6020 Innsbruck, Austria
| | - Hubert Hackl
- Division of Bioinformatics, Biocenter, Innsbruck Medical University, 6020 Innsbruck, Austria
| | - Bettina Sartori
- Division of Hygiene and Medical Microbiology, Innsbruck Medical University, 6020 Innsbruck, Austria
| | - Cornelia Lass-Flörl
- Division of Hygiene and Medical Microbiology, Innsbruck Medical University, 6020 Innsbruck, Austria
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Speth C, Löffler J, Krappmann S, Lass-Flörl C, Rambach G. Platelets as immune cells in infectious diseases. Future Microbiol 2013; 8:1431-51. [DOI: 10.2217/fmb.13.104] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Platelets have been shown to cover a broad range of functions. Besides their role in hemostasis, they have immunological functions and thus participate in the interaction between pathogens and host defense. Platelets have a broad repertoire of receptor molecules that enable them to sense invading pathogens and infection-induced inflammation. Consequently, platelets exert antimicrobial effector mechanisms, but also initiate an intense crosstalk with other arms of the innate and adaptive immunity, including neutrophils, monocytes/macrophages, dendritic cells, B cells and T cells. There is a fragile balance between beneficial antimicrobial effects and detrimental reactions that contribute to the pathogenesis, and many pathogens have developed mechanisms to influence these two outcomes. This review aims to highlight aspects of the interaction strategies between platelets and pathogenic bacteria, viruses, fungi and parasites, in addition to the subsequent networking between platelets and other immune cells, and the relevance of these processes for the pathogenesis of infections.
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Affiliation(s)
- Cornelia Speth
- Division of Hygiene & Medical Microbiology, Innsbruck Medical University Fritz-Pregl-Straße 3, A-6020 Innsbruck, Austria
| | - Jürgen Löffler
- Laboratory of Innate Immunity, Infection, Inflammation, University Hospital Würzburg, Würzburg, Germany
| | - Sven Krappmann
- Microbiology Institute – Clinical Microbiology, Immunology & Hygiene, University Hospital of Erlangen & Friedrich-Alexander-University Erlangen-Nürnberg, Germany
| | - Cornelia Lass-Flörl
- Division of Hygiene & Medical Microbiology, Innsbruck Medical University Fritz-Pregl-Straße 3, A-6020 Innsbruck, Austria
| | - Günter Rambach
- Division of Hygiene & Medical Microbiology, Innsbruck Medical University Fritz-Pregl-Straße 3, A-6020 Innsbruck, Austria
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Lass-Flörl C, Roilides E, Löffler J, Wilflingseder D, Romani L. Minireview: host defence in invasive aspergillosis. Mycoses 2013; 56:403-13. [PMID: 23406508 DOI: 10.1111/myc.12052] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Aspergillus is a saprophytic fungus, which mainly becomes pathogenic in immunosuppressed hosts. A failure of host defences results in a diverse set of illnesses, ranging from chronic colonisation, aspergilloma, invasive disease and hypersensitivity. A key concept in immune responses to Aspergillus species is that host susceptibility determines the morphological form, antigenic structure and physical location of the fungus. Traditionally, innate immunity has been considered as a first line of defence and activates adaptive immune mechanisms by the provision of specific signals; innate and adaptive immune responses are intimately linked. The T-helper cell (TH 1) response is associated with increased production of inflammatory cytokines IFN-γ, IL-2 and IL-12 and stimulation of antifungal effector cells. Alternatively, TH 2-type responses are associated with suppression of antifungal effector cell activity, decreased production of IFN-γ and increased concentrations of IL-4 and IL-10, which promote humoral responses to Aspergillus. The host's defensive capacity is defined by the sum of resistance and tolerance. Resistance displays the ability to limit fungal burden and elimination of the pathogen, and tolerance means the ability to limit host damage caused by immune response.
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Affiliation(s)
- Cornelia Lass-Flörl
- Division of Hygiene and Medical Microbiology, Innsbruck Medical University, Innsbruck, Austria.
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Speth C, Hagleitner M, Ott HW, Würzner R, Lass-Flörl C, Rambach G. Aspergillus
fumigatus Activates Thrombocytes by Secretion of Soluble Compounds. J Infect Dis 2012; 207:823-33. [DOI: 10.1093/infdis/jis743] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Interaction of platelets and anidulafungin against Aspergillus fumigatus. Antimicrob Agents Chemother 2012; 57:626-8. [PMID: 23114752 DOI: 10.1128/aac.01534-12] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The combination of platelets and anidulafungin at 0.03 μg/ml significantly (P < 0.05) reduced the germination rate and hyphal elongation in Aspergillus fumigatus compared to those with either anidulafungin only or an untreated control. Platelets decreased the expression of the fks gene, which plays an important role in cell wall synthesis. Our results suggest that human platelets plus anidulafungin might contribute to defense against A. fumigatus.
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Perkhofer S, Trappl K, Striessnig B, Nussbaumer W, Lass-Flörl C. Platelets enhance activity of antimycotic substances against non-Aspergillus fumigatus Aspergillus species in vitro. Med Mycol 2010; 49:157-66. [PMID: 20795763 DOI: 10.3109/13693786.2010.510150] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Platelets are known to be part of haemostasis but they are also players in innate host defense. Recently, we observed that platelets attenuate the virulence of Aspergillus spp. in vitro. However, little is known about the antifungal effects of platelets in the presence of antimycotics against non-A. fumigatus Aspergillus species. We therefore investigated whether platelets increase the in vitro activity of amphotericin B, voriconazole, posaconazole and caspofungin against two clinical isolates each of Aspergillus flavus, Aspergillus terreus and Aspergillus niger. The antifungal activity was evaluated by assessing germination percentages, hyphal elongation and hyphal damage by use of XTT. The combination of platelets plus amphotericin B significantly (P < 0.05) enhanced the reduction of germination percentage compared to either substance alone. Among triazoles, voriconazole exhibited significant effects with platelets for all tested aspergilli. Overall, these findings suggest that among the tested antimycotic substances, amphotericin B in combination with platelets has enhancing effects in reducing germination and hyphal elongation in the tested non-A. fumigatus Aspergillus species. These data indicate that platelets act beneficially with antimycotics in an early stage of fungal growth by blocking and/or delaying fungal germination and hyphal elongation; both crucial mechanisms in the development of invasive fungal disease.
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Affiliation(s)
- Susanne Perkhofer
- Division of Hygiene and Medical Microbiology, Medical University Innsbruck, Innsbruck, Austria.
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Abstract
All humans are continuously exposed to inhaled Aspergillus conidia, yet healthy hosts clear the organism without developing disease and without the development of antibody- or cell-mediated acquired immunity to this organism. This suggests that for most healthy humans, innate immunity is sufficient to clear the organism. A failure of these defenses results in a uniquely diverse set of illnesses caused by Aspergillus species, which includes diseases caused by the colonization of the respiratory tract, invasive infection, and hypersensitivity. A key concept in immune responses to Aspergillus species is that the susceptibilities of the host determine the morphological form, antigenic structure, and physical location of the fungus. In this review, we summarize the current literature on the multiple layers of innate defenses against Aspergillus species that dictate the outcome of this host-microbe interaction.
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Perkhofer S, Kehrel BE, Dierich MP, Donnelly JP, Nussbaumer W, Hofmann J, von Eiff C, Lass-Flörl C. Human platelets attenuate Aspergillus species via granule-dependent mechanisms. J Infect Dis 2008; 198:1243-6. [PMID: 18752432 DOI: 10.1086/591458] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Using laser scanning microscopy, we investigated whether platelets are capable of internalizing Aspergillus conidia and examined Aspergillus-platelet adherence. The influence of platelets on fungal growth was evaluated by assessing galactomannan (GM) release, hyphal elongation, and colony size. A secretion assay with [(3)H]-serotonin (5-hydroxytryptamine [5-HT]) was performed. Exposure to platelets resulted in significantly decreased GM release (p<.05), hyphal elongation (p<.001), colony size, pigmentation, and 5-HT release ( p<.05). A lack of antifungal effects was observed with the microfilament inhibitor cytochalasin D. Platelets attenuate the virulence of Aspergillus species in vitro on the basis of granule-dependent effects.
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