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Lamoth F, Prakash K, Beigelman-Aubry C, Baddley JW. Lung and sinus fungal infection imaging in immunocompromised patients. Clin Microbiol Infect 2024; 30:296-305. [PMID: 37604274 DOI: 10.1016/j.cmi.2023.08.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 08/06/2023] [Accepted: 08/13/2023] [Indexed: 08/23/2023]
Abstract
BACKGROUND Imaging is a key diagnostic modality for suspected invasive pulmonary or sinus fungal disease and may help to direct testing and treatment. Fungal diagnostic guidelines have been developed and emphasize the role of imaging in this setting. We review and summarize evidence regarding imaging for fungal pulmonary and sinus disease (in particular invasive aspergillosis, mucormycosis and pneumocystosis) in immunocompromised patients. OBJECTIVES We reviewed data on imaging modalities and findings used for diagnosis of invasive fungal pulmonary and sinus disease. SOURCES References for this review were identified by searches of PubMed, Google Scholar, Embase and Web of Science through 1 April 1 2023. CONTENT Computed tomography imaging is the method of choice for the evaluation of suspected lung or sinus fungal disease. Although no computed tomography radiologic pattern is pathognomonic of pulmonary invasive fungal disease (IFD) the halo sign firstly suggests an angio-invasive pulmonary aspergillosis while the Reversed Halo Sign is more suggestive of pulmonary mucormycosis in an appropriate clinical setting. The air crescent sign is uncommon, occurring in the later stages of invasive aspergillosis in neutropenic patients. In contrast, new cavitary lesions should suggest IFD in moderately immunocompromised patients. Regarding sinus site, bony erosion, peri-antral fat or septal ulceration are reasonably predictive of IFD. IMPLICATIONS Imaging assessment of the lung and sinuses is an important component of the diagnostic work-up and management of IFD in immunocompromised patients. However, radiological features signs have sensitivity and specificity that often vary according to underlying disease states. Periodic review of imaging studies and diagnostic guidelines characterizing imaging findings may help clinicians to consider fungal infections in clinical care thereby leading to an earlier confirmation and treatment of IFD.
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Affiliation(s)
- Frederic Lamoth
- Service of Infectious Diseases, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland; Institute of Microbiology, Department of Laboratory Medicine and Microbiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Katya Prakash
- Division of Infectious Diseases, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Catherine Beigelman-Aubry
- Radiodiagnostic and Interventional Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - John W Baddley
- Division of Infectious Diseases, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, USA.
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Lai J, Wang B, Petrik M, Beziere N, Hammoud DA. Radiotracer Development for Fungal-Specific Imaging: Past, Present, and Future. J Infect Dis 2023; 228:S259-S269. [PMID: 37788500 PMCID: PMC10547453 DOI: 10.1093/infdis/jiad067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023] Open
Abstract
Invasive fungal infections have become a major challenge for public health, mainly due to the growing numbers of immunocompromised patients, with high morbidity and mortality. Currently, conventional imaging modalities such as computed tomography and magnetic resonance imaging contribute largely to the noninvasive diagnosis and treatment evaluation of those infections. These techniques, however, often fall short when a fast, noninvasive and specific diagnosis of fungal infection is necessary. Molecular imaging, especially using nuclear medicine-based techniques, aims to develop fungal-specific radiotracers that can be tested in preclinical models and eventually translated to human applications. In the last few decades, multiple radioligands have been developed and tested as potential fungal-specific tracers. These include radiolabeled peptides, antifungal drugs, siderophores, fungal-specific antibodies, and sugars. In this review, we provide an overview of the pros and cons of the available radiotracers. We also address the future prospects of fungal-specific imaging.
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Affiliation(s)
- Jianhao Lai
- Center for Infectious Disease Imaging, Radiology, and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Benjamin Wang
- Center for Infectious Disease Imaging, Radiology, and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Milos Petrik
- Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacky University Olomouc, Olomouc, Czech Republic
- Czech Advanced Technology and Research Institute, Palacky University Olomouc, Olomouc, Czech Republic
| | - Nicolas Beziere
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
- Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Dima A Hammoud
- Center for Infectious Disease Imaging, Radiology, and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
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Happacher I, Aguiar M, Yap A, Decristoforo C, Haas H. Fungal siderophore metabolism with a focus on Aspergillus fumigatus: impact on biotic interactions and potential translational applications. Essays Biochem 2023; 67:829-842. [PMID: 37313590 PMCID: PMC10500206 DOI: 10.1042/ebc20220252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/22/2023] [Accepted: 05/26/2023] [Indexed: 06/15/2023]
Abstract
Iron is an essential trace element that is limiting in most habitats including hosts for fungal pathogens. Siderophores are iron-chelators synthesized by most fungal species for high-affinity uptake and intracellular handling of iron. Moreover, virtually all fungal species including those lacking siderophore biosynthesis appear to be able to utilize siderophores produced by other species. Siderophore biosynthesis has been shown to be crucial for virulence of several fungal pathogens infecting animals and plants revealing induction of this iron acquisition system during virulence, which offers translational potential of this fungal-specific system. The present article summarizes the current knowledge on the fungal siderophore system with a focus on Aspergillus fumigatus and its potential translational application including noninvasive diagnosis of fungal infections via urine samples, imaging of fungal infections via labeling of siderophores with radionuclides such as Gallium-68 for detection with positron emission tomography, conjugation of siderophores with fluorescent probes, and development of novel antifungal strategies.
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Affiliation(s)
- Isidor Happacher
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Mario Aguiar
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Annie Yap
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Hubertus Haas
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
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Lamoth F. Novel Approaches in the Management of Mucormycosis. CURRENT FUNGAL INFECTION REPORTS 2023; 17:1-10. [PMID: 37360854 PMCID: PMC10165581 DOI: 10.1007/s12281-023-00463-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2023] [Indexed: 06/28/2023]
Abstract
Purpose of Review Invasive mucormycosis (IM), caused by fungi of the order Mucorales, is one of the deadliest fungal infection among hematologic cancer patients. Its incidence is also increasingly reported in immunocompetent individuals, notably with the COVID-19 pandemic. Therefore, there is an urgent need for novel diagnostic and therapeutic approaches of IM. This review discusses the current advances in this field. Recent Findings Early diagnosis of IM is crucial and can be improved by Mucorales-specific PCR and development of lateral-flow immunoassays for specific antigen detection. The spore coat proteins (CotH) are essential for virulence of the Mucorales and may represent a target for novel antifungal therapies. Adjuvant therapies boosting the immune response, such as interferon-γ, anti-PDR1 or fungal-specific chimeric antigen receptor (CAR) T-cells, are also considered. Summary The most promising perspectives for improved management of IM consist of a multilayered approach targeting both the pathogen and the host immune system.
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Affiliation(s)
- Frederic Lamoth
- Service of Infectious Diseases, Department of Medicine, Lausanne University Hospital, University of Lausanne, Rue du Bugnon 48, 1011 Lausanne, Switzerland
- Institute of Microbiology, Department of Laboratory Medicine and Pathology, Lausanne University Hospital, University of Lausanne, Rue du Bugnon 48, 1011 Lausanne, Switzerland
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Luptáková D, Patil RH, Dobiáš R, Stevens DA, Pluháček T, Palyzová A, Káňová M, Navrátil M, Vrba Z, Hubáček P, Havlíček V. Siderophore-Based Noninvasive Differentiation of Aspergillus fumigatus Colonization and Invasion in Pulmonary Aspergillosis. Microbiol Spectr 2023; 11:e0406822. [PMID: 36719229 PMCID: PMC10100950 DOI: 10.1128/spectrum.04068-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 01/06/2023] [Indexed: 02/01/2023] Open
Abstract
Germination from conidia to hyphae and hyphal propagation of Aspergillus fumigatus are the key pathogenic steps in the development of invasive pulmonary aspergillosis (IPA). By applying in vitro observations in a clinical study of 13 patients diagnosed with probable IPA, here, we show that the transition from colonization to the A. fumigatus invasive stage is accompanied by the secretion of triacetylfusarinine C (TafC), triacetylfusarinine B (TafB), and ferricrocin (Fc) siderophores into urine, with strikingly better sensitivity performance than serum sampling. The best-performing index, the TafC/creatinine index, with a median value of 17.2, provided 92.3% detection sensitivity (95% confidence interval [CI], 64.0 to 99.8%) and 100% specificity (95% CI, 84.6 to 100%), i.e., substantially better than the corresponding indications provided by galactomannan (GM) and β-d-glucan (BDG) serology. For the same patient cohort, the serum GM and BDG sensitivities were 46.2 and 76.9%, respectively, and their specificities were 86.4 and 63.6%, respectively. The time-dependent specific appearance of siderophores in the host's urine represents an impactful clinical diagnostic advantage in the early discrimination of invasive aspergillosis from colonization. A favorable concentration of TafC in a clinical specimen distant from a deep infection site enables the noninvasive sampling of patients suffering from IPA. IMPORTANCE The importance of this research lies in the demonstration that siderophore analysis can distinguish between asymptomatic colonization and invasive pulmonary aspergillosis. We found clear associations between phases of fungal development, from conidial germination to the proliferative stage of invasive aspergillosis, and changes in secondary metabolite secretion. The critical extracellular fungal metabolites triacetylfusarinines C and B are produced during the polarized germination or postpolarized growth phase and reflect the morphological status of the proliferating pathogen. False positivity in Aspergillus diagnostics is minimized as mammalian cells do not synthesize Aspergillus siderophore or mycotoxin molecules.
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Affiliation(s)
- Dominika Luptáková
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Rutuja H. Patil
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
- Department of Analytical Chemistry, Palacký University, Olomouc, Czechia
| | - Radim Dobiáš
- Department of Bacteriology and Mycology, Public Health Institute in Ostrava, Ostrava, Czechia
- Institute of Laboratory Medicine, Faculty of Medicine, University of Ostrava, Ostrava, Czechia
| | - David A. Stevens
- California Institute for Medical Research, San Jose, California, USA
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Tomáš Pluháček
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
- Department of Analytical Chemistry, Palacký University, Olomouc, Czechia
| | - Andrea Palyzová
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Marcela Káňová
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Ostrava, Ostrava, Czechia
- Institute of Physiology and Pathophysiology, Faculty of Medicine, University of Ostrava, Ostrava, Czechia
- Department of Intensive Medicine, Emergency Medicine and Forensic Studies, University of Ostrava, Ostrava, Czechia
| | - Milan Navrátil
- Department of Hematooncology, University Hospital Ostrava, Ostrava, Czechia
| | - Zbyněk Vrba
- Lung Department, Krnov Combined Medical Facility, Krnov, Czechia
| | - Petr Hubáček
- Department of Medical Microbiology, Charles University, Prague, Czechia
- Motol University Hospital, Prague, Czechia
| | - Vladimír Havlíček
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
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Akter A, Lyons O, Mehra V, Isenman H, Abbate V. Radiometal chelators for infection diagnostics. FRONTIERS IN NUCLEAR MEDICINE (LAUSANNE, SWITZERLAND) 2023; 2:1058388. [PMID: 37388440 PMCID: PMC7614707 DOI: 10.3389/fnume.2022.1058388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/01/2023]
Abstract
Infection of native tissues or implanted devices is common, but clinical diagnosis is frequently difficult and currently available noninvasive tests perform poorly. Immunocompromised individuals (for example transplant recipients, or those with cancer) are at increased risk. No imaging test in clinical use can specifically identify infection, or accurately differentiate bacterial from fungal infections. Commonly used [18F]fluorodeoxyglucose (18FDG) positron emission computed tomography (PET/CT) is sensitive for infection, but limited by poor specificity because increased glucose uptake may also indicate inflammation or malignancy. Furthermore, this tracer provides no indication of the type of infective agent (bacterial, fungal, or parasitic). Imaging tools that directly and specifically target microbial pathogens are highly desirable to improve noninvasive infection diagnosis and localization. A growing field of research is exploring the utility of radiometals and their chelators (siderophores), which are small molecules that bind radiometals and form a stable complex allowing sequestration by microbes. This radiometal-chelator complex can be directed to a specific microbial target in vivo, facilitating anatomical localization by PET or single photon emission computed tomography. Additionally, bifunctional chelators can further conjugate therapeutic molecules (e.g., peptides, antibiotics, antibodies) while still bound to desired radiometals, combining specific imaging with highly targeted antimicrobial therapy. These novel therapeutics may prove a useful complement to the armamentarium in the global fight against antimicrobial resistance. This review will highlight current state of infection imaging diagnostics and their limitations, strategies to develop infection-specific diagnostics, recent advances in radiometal-based chelators for microbial infection imaging, challenges, and future directions to improve targeted diagnostics and/or therapeutics.
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Affiliation(s)
- Asma Akter
- Department of Analytical, Environmental and Forensic Sciences, King’s College London, London, United Kingdom
| | - Oliver Lyons
- Vascular Endovascular and Transplant Surgery, Christchurch Public Hospital, Christchurch, New Zealand
- Department of Surgery, University of Otago, Christchurch, New Zealand
| | - Varun Mehra
- Department of Hematology, King’s College Hospital NHS Foundation Trust, London, United Kingdom
| | - Heather Isenman
- Department of Infectious Diseases, General Medicine, Christchurch Hospital, Christchurch, New Zealand
| | - Vincenzo Abbate
- Department of Analytical, Environmental and Forensic Sciences, King’s College London, London, United Kingdom
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7
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Ankrah AO, Lawal IO, Dierckx RAJO, Sathekge MM, Glaudemans AWJM. Imaging of Invasive Fungal Infections- The Role of PET/CT. Semin Nucl Med 2023; 53:57-69. [PMID: 35933165 DOI: 10.1053/j.semnuclmed.2022.07.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/06/2022] [Accepted: 07/07/2022] [Indexed: 01/28/2023]
Abstract
Over the last decades, the population at risk for invasive fungal disease (IFD) has increased because of medical therapy advances and diseases compromising patients' immune systems. The high morbidity and mortality associated with invasive fungal disease in the immunocompromised present the challenge of early diagnosis of the IFD and the need to closely monitor the infection during treatment. The definitive diagnosis of invasive fungal disease based on culture or histopathological methods often has reduced diagnostic accuracy in the immunocompromised and may be very invasive. Less invasive and indirect evidence of the fungal infection by serology and imaging has been used for the early diagnosis of fungal infection before definitive results are available or when the definitive methods of diagnosis are suboptimal. Imaging in invasive fungal disease is a non-invasive biomarker that helps in the early diagnosis of invasive fungal disease but helps follow-up the infection during treatment. Different imaging modalities are used in the workup to evaluate fungal disease. The different imaging modalities have advantages and disadvantages at different sites in the body and may complement each other in the management of IFD. Positron emission tomography integrated with computed tomography with [18F]Fluorodeoxyglucose (FDG PET/CT) has helped manage IFD. The combined functional data from PET and anatomical data from the CT from almost the whole body allows noninvasive evaluation of IFD and provides a semiquantitative means of assessing therapy. FDG PET/CT adds value to anatomic-based only imaging modalities. The nonspecificity of FDG uptake has led to the evaluation of other tracers in the assessment of IFD. However, these are mainly still at the preclinical level and are yet to be translated to humans. FDG PET/CT remains the most widely evaluated radionuclide-based imaging modality in IFD management. The limitations of FDG PET/CT must be well understood, and more extensive prospective studies in uniform populations are needed to validate its role in the management of IFD that can be international guidelines.
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Affiliation(s)
- Alfred O Ankrah
- National Centre for Radiotherapy Oncology and Nuclear Medicine, Korle Bu Teaching Hospital, Accra GA, Ghana; Department of Nuclear Medicine, University of Pretoria, Steve Biko Academic Hospital, Pretoria, South Africa; Medical Imaging Center, University Medical Center Groningen, University of Groningen, RB Groningen, The Netherlands.
| | - Ismaheel O Lawal
- Department of Nuclear Medicine, University of Pretoria, Steve Biko Academic Hospital, Pretoria, South Africa; Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA
| | - Rudi A J O Dierckx
- Medical Imaging Center, University Medical Center Groningen, University of Groningen, RB Groningen, The Netherlands
| | - Mike M Sathekge
- Department of Nuclear Medicine, University of Pretoria, Steve Biko Academic Hospital, Pretoria, South Africa
| | - Andor W J M Glaudemans
- Medical Imaging Center, University Medical Center Groningen, University of Groningen, RB Groningen, The Netherlands
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Abstract
PURPOSE OF REVIEW Invasive fungal diseases (IFDs) such as invasive aspergillosis continue to be associated with high morbidity and mortality while presenting significant diagnostic challenges. Siderophores are high-affinity Fe 3+ chelators produced by Aspergillus spp. and other fungi capable of causing IFD. Previously evaluated as a treatment target in mucormycosis, siderophores have recently emerged as new diagnostic targets for invasive aspergillosis and scedosporiosis. Here, we review the diagnostic potential of siderophores for diagnosing IFD, with a particular focus on invasive aspergillosis. RECENT FINDINGS The major secreted siderophore of A. fumigatus , triacetylfusarinine C (TAFC), has been successfully detected by mass spectrometry in serum, BALF and urine of patients with invasive aspergillosis, with promising sensitivities and specificities in single-centre studies. Intracellular uptake of siderophores has also been utilized for imaging, wherein fungal siderophores have been conjugated with the easy-to-produce radioactive isotope gallium-68 ( 68 Ga) to visualize infected body sites in PET. For the Scedosporium apiospermum complex, another siderophore N(α)-methyl coprogen B has been shown promising as a marker for airway colonization in early studies. SUMMARY Siderophores and particular TAFC have the potential to revolutionize diagnostic pathways for invasive aspergillosis and other mould infections. However, larger multicentre studies are needed to confirm these promising performances. Methods that allow rapid and cost-effective measurements in routine clinical practice need to be developed, particularly when TAFC is used as a biomarker in patient specimens.
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Aguiar M, Orasch T, Shadkchan Y, Caballero P, Pfister J, Sastré-Velásquez LE, Gsaller F, Decristoforo C, Osherov N, Haas H. Uptake of the Siderophore Triacetylfusarinine C, but Not Fusarinine C, Is Crucial for Virulence of Aspergillus fumigatus. mBio 2022; 13:e0219222. [PMID: 36125294 PMCID: PMC9600649 DOI: 10.1128/mbio.02192-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/02/2022] [Indexed: 11/20/2022] Open
Abstract
Siderophores play an important role in fungal virulence, serving as trackers for in vivo imaging and as biomarkers of fungal infections. However, siderophore uptake is only partially characterized. As the major cause of aspergillosis, Aspergillus fumigatus is one of the most common airborne fungal pathogens of humans. Here, we demonstrate that this mold species mediates the uptake of iron chelated by the secreted siderophores triacetylfusarinine C (TAFC) and fusarinine C by the major facilitator-type transporters MirB and MirD, respectively. In a murine aspergillosis model, MirB but not MirD was found to be crucial for virulence, indicating that TAFC-mediated uptake plays a dominant role during infection. In the absence of MirB, TAFC becomes inhibitory by decreasing iron availability because the mutant is not able to recognize iron that is chelated by TAFC. MirB-mediated transport was found to tolerate the conjugation of fluorescein isothiocyanate to triacetylfusarinine C, which might aid in the development of siderophore-based antifungals in a Trojan horse approach, particularly as the role of MirB in pathogenicity restrains its mutational inactivation. Taken together, this study identified the first eukaryotic siderophore transporter that is crucial for virulence and elucidated its translational potential as well as its evolutionary conservation. IMPORTANCE Aspergillus fumigatus is responsible for thousands of cases of invasive fungal disease annually. For iron uptake, A. fumigatus secretes so-called siderophores, which are taken up after the binding of environmental iron. Moreover, A. fumigatus can utilize siderophore types that are produced by other fungi or bacteria. Fungal siderophores raised considerable interest due to their role in virulence and their potential for the diagnosis and treatment of fungal infections. Here, we demonstrate that the siderophore transporter MirB is crucial for the virulence of A. fumigatus, which reveals that its substrate, triacetylfusarinine C, is the most important siderophore during infection. We found that in the absence of MirB, TAFC becomes inhibitory by decreasing the availability of environmental iron and that MirB-mediated transport tolerates the derivatization of its substrate, which might aid in the development of siderophore-based antifungals. This study significantly improved the understanding of fungal iron homeostasis and the role of siderophores in interactions with the host.
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Affiliation(s)
- Mario Aguiar
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Thomas Orasch
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Yana Shadkchan
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine Ramat-Aviv, Tel Aviv, Israel
| | - Patricia Caballero
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Joachim Pfister
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck, Austria
| | | | - Fabio Gsaller
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Nir Osherov
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine Ramat-Aviv, Tel Aviv, Israel
| | - Hubertus Haas
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
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10
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Abstract
AbstractAspergillosis is one of the most frequent fungal infections, whose morbidity can be life-threatening, especially in some categories of patients such as immunocompromised ones. It can have various clinical presentation scenarios and should be considered when making differential diagnosis in patients with pulmonary and extrapulmonary involvement. 18F-FDG PET/CT is a whole-body diagnostic technique that can help in the study of the disease, guiding the patient management thanks to the possibility to recognize infection sites and extension. The aim of this manuscript is to provide an overview of the wide spectrum of disease presentation. Literature regarding 18F-FDG PET/CT in histologically confirmed aspergillosis cases has been revised to describe all its possible features, both usual and unusual to guide imaging interpretation. 18F-FDG PET/CT is a diagnostic tool that can help in the recognition of the heterogenous infection’s presentation, allowing the clinicians to make a prompt diagnosis and to have the most accurate management of the disease. Furthermore, other PET/CT radiopharmaceutical role in Aspergillosis imaging study have been presented.
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Jensen LJ, Kim D, Elgeti T, Steffen IG, Hamm B, Nagel SN. Differentiation of Pulmonary Lymphoma Manifestations and Nonlymphoma Infiltrates in Possible Invasive Fungal Disease Using Fast T1-weighted Magnetic Resonance Imaging at 3 T Comparison of Texture Analysis, Mapping, and Signal Intensity Quotients. J Thorac Imaging 2022; 37:80-89. [PMID: 34269753 DOI: 10.1097/rti.0000000000000606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE This study aimed to evaluate the diagnostic performance of texture analysis (TA), T1 mapping, and signal intensity quotients derived from fast T1-weighted gradient echo (T1w GRE) sequences for differentiating pulmonary lymphoma manifestations and nonlymphoma infiltrates in possible invasive fungal disease in immunocompromised hematological patients. MATERIALS AND METHODS Twenty patients with hematologic malignancies and concomitant immunosuppression (including 10 patients with pulmonary lymphoma manifestations and 10 patients with nonlymphoma infiltrates) prospectively underwent 3 T magnetic resonance imaging using a conventional T1w GRE sequence and a T1w GRE mapping sequence with variable flip angle. A region of interest was placed around the most representative lesion in each patient. TA was performed using PyRadiomics. T1 relaxation times were extracted from precompiled maps and calculated manually. Signal intensity quotients (lesion/muscle) were calculated from conventional T1w GRE sequences. RESULTS Of all TA features, variance, mean absolute deviation, robust mean absolute deviation, interquartile range, and minimum were significantly different between the 2 entities (P<0.05), with excellent diagnostic performance in receiver operating characteristic analysis (area under the curve [AUC] >80%). Neither T1 relaxation times from precompiled maps (AUC=63%; P=0.353) nor manual calculation (AUC=63%; P=0.353) nor signal intensity quotients (AUC=70%; P=0.143) yielded significant differences. CONCLUSIONS TA from fast T1w GRE images can differentiate pulmonary lymphoma manifestations and nonlymphoma infiltrates in possible invasive fungal disease with excellent diagnostic performance using the TA features variance, mean absolute deviation, robust mean absolute deviation, interquartile range, and minimum. Combining a fast T1w GRE sequence with TA seems to be a promising tool to differentiate these 2 entities noninvasively.
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Affiliation(s)
| | | | - Thomas Elgeti
- Pediatric Radiology, Charité University Medicine Berlin, Corporate Member of Free University of Berlin, Humboldt University of Berlin, Berlin, Germany
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Ariztia J, Solmont K, Moïse NP, Specklin S, Heck MP, Lamandé-Langle S, Kuhnast B. PET/Fluorescence Imaging: An Overview of the Chemical Strategies to Build Dual Imaging Tools. Bioconjug Chem 2022; 33:24-52. [PMID: 34994545 DOI: 10.1021/acs.bioconjchem.1c00503] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Molecular imaging is a biomedical research discipline that has quickly emerged to afford the observation, characterization, monitoring, and quantification of biomarkers and biological processes in living organism. It covers a large array of imaging techniques, each of which provides anatomical, functional, or metabolic information. Multimodality, as the combination of two or more of these techniques, has proven to be one of the best options to boost their individual properties, hence offering unprecedented tools for human health. In this review, we will focus on the combination of positron emission tomography and fluorescence imaging from the specific perspective of the chemical synthesis of dual imaging agents. Based on a detailed analysis of the literature, this review aims at giving a comprehensive overview of the chemical strategies implemented to build adequate imaging tools considering radiohalogens and radiometals as positron emitters, fluorescent dyes mostly emitting in the NIR window and all types of targeting vectors.
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Affiliation(s)
- Julen Ariztia
- Université Paris-Saclay, Inserm, CNRS, CEA, Laboratoire d'Imagerie Biomédicale Multimodale Paris-Saclay, 91401, Orsay, France
| | - Kathleen Solmont
- Université Paris-Saclay, Inserm, CNRS, CEA, Laboratoire d'Imagerie Biomédicale Multimodale Paris-Saclay, 91401, Orsay, France
| | | | - Simon Specklin
- Université Paris-Saclay, Inserm, CNRS, CEA, Laboratoire d'Imagerie Biomédicale Multimodale Paris-Saclay, 91401, Orsay, France
| | - Marie Pierre Heck
- Université Paris-Saclay, INRAE, Département Médicaments et Technologies pour la santé (DMTS), SCBM, 91191, Gif-sur-Yvette cedex, France
| | | | - Bertrand Kuhnast
- Université Paris-Saclay, Inserm, CNRS, CEA, Laboratoire d'Imagerie Biomédicale Multimodale Paris-Saclay, 91401, Orsay, France
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Decristoforo C, Pfister J. In vitro studies with radiopharmaceuticals. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00012-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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14
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Leroy-Freschini B, Imperiale A. PET imaging in invasive fungal infection. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00022-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Evaluation of 2-[ 18F]-Fluorodeoxysorbitol PET Imaging in Preclinical Models of Aspergillus Infection. J Fungi (Basel) 2021; 8:jof8010025. [PMID: 35049965 PMCID: PMC8780649 DOI: 10.3390/jof8010025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 12/13/2022] Open
Abstract
Despite increasing associated mortality and morbidity, the diagnosis of fungal infections, especially with Aspergillus fumigatus (A. fumigatus), remains challenging. Based on known ability of Aspergillus species to utilize sorbitol, we evaluated 2-[18F]-fluorodeoxysorbitol (FDS), a recently described Enterobacterales imaging ligand, in animal models of A. fumigatus infection, in comparison with 2-[18F]-fluorodeoxyglucose (FDG). In vitro assays showed slightly higher 3H-sorbitol uptake by live compared with heat-killed A. fumigatus. However, this was 10.6-fold lower than E. coli uptake. FDS positron emission tomography (PET) imaging of A. fumigatus pneumonia showed low uptake in infected lungs compared with FDG (0.290 ± 0.030 vs. 8.416 ± 0.964 %ID/mL). This uptake was higher than controls (0.098 ± 0.008 %ID/mL) and minimally higher than lung inflammation (0.167 ± 0.007 %ID/mL). In the myositis models, FDS uptake was highest in live E. coli infections. Uptake was low in A. fumigatus myositis model and only slightly higher in live compared with the heat-killed side. In conclusion, we found low uptake of 3H-sorbitol and FDS by A. fumigatus cultures and infection models compared with E. coli, likely due to the need for induction of sorbitol dehydrogenase by sorbitol. Our findings do not support FDS as an Aspergillus imaging agent. At this point, FDS remains more selective for imaging Gram-negative Enterobacterales.
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Pecoraro L, Wang X, Shah D, Song X, Kumar V, Shakoor A, Tripathi K, Ramteke PW, Rani R. Biosynthesis Pathways, Transport Mechanisms and Biotechnological Applications of Fungal Siderophores. J Fungi (Basel) 2021; 8:21. [PMID: 35049961 PMCID: PMC8781417 DOI: 10.3390/jof8010021] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 12/21/2021] [Accepted: 12/21/2021] [Indexed: 11/16/2022] Open
Abstract
Iron (Fe) is the fourth most abundant element on earth and represents an essential nutrient for life. As a fundamental mineral element for cell growth and development, iron is available for uptake as ferric ions, which are usually oxidized into complex oxyhydroxide polymers, insoluble under aerobic conditions. In these conditions, the bioavailability of iron is dramatically reduced. As a result, microorganisms face problems of iron acquisition, especially under low concentrations of this element. However, some microbes have evolved mechanisms for obtaining ferric irons from the extracellular medium or environment by forming small molecules often regarded as siderophores. Siderophores are high affinity iron-binding molecules produced by a repertoire of proteins found in the cytoplasm of cyanobacteria, bacteria, fungi, and plants. Common groups of siderophores include hydroxamates, catecholates, carboxylates, and hydroximates. The hydroxamate siderophores are commonly synthesized by fungi. L-ornithine is a biosynthetic precursor of siderophores, which is synthesized from multimodular large enzyme complexes through non-ribosomal peptide synthetases (NRPSs), while siderophore-Fe chelators cell wall mannoproteins (FIT1, FIT2, and FIT3) help the retention of siderophores. S. cerevisiae, for example, can express these proteins in two genetically separate systems (reductive and nonreductive) in the plasma membrane. These proteins can convert Fe (III) into Fe (II) by a ferrous-specific metalloreductase enzyme complex and flavin reductases (FREs). However, regulation of the siderophore through Fur Box protein on the DNA promoter region and its activation or repression depend primarily on the Fe availability in the external medium. Siderophores are essential due to their wide range of applications in biotechnology, medicine, bioremediation of heavy metal polluted environments, biocontrol of plant pathogens, and plant growth enhancement.
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Affiliation(s)
- Lorenzo Pecoraro
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300072, China; (X.W.); (D.S.); (X.S.); (A.S.); (R.R.)
| | - Xiao Wang
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300072, China; (X.W.); (D.S.); (X.S.); (A.S.); (R.R.)
| | - Dawood Shah
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300072, China; (X.W.); (D.S.); (X.S.); (A.S.); (R.R.)
- Institute of Biotechnology and Genetic Engineering, The University of Agriculture Peshawar, Peshawar 25000, Pakistan
| | - Xiaoxuan Song
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300072, China; (X.W.); (D.S.); (X.S.); (A.S.); (R.R.)
| | - Vishal Kumar
- Department of Food Science and Technology, Yeungnam University, Gyongsan 38541, Korea;
| | - Abdul Shakoor
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300072, China; (X.W.); (D.S.); (X.S.); (A.S.); (R.R.)
- College of Geography and Environmental Science, Henan University, Kaifeng 475004, China
| | - Keshawanand Tripathi
- Center for Conservation and Utilization of Blue-Green Algae, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India;
| | - Pramod W. Ramteke
- Faculty of Life Sciences, Mandsaur University, Mandsaur 458001, India;
| | - Rupa Rani
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300072, China; (X.W.); (D.S.); (X.S.); (A.S.); (R.R.)
- Department of Environmental Science and Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad 826004, India
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Radionuclide Imaging of Invasive Fungal Disease in Immunocompromised Hosts. Diagnostics (Basel) 2021; 11:diagnostics11112057. [PMID: 34829403 PMCID: PMC8620393 DOI: 10.3390/diagnostics11112057] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/03/2021] [Accepted: 11/04/2021] [Indexed: 12/19/2022] Open
Abstract
Invasive fungal disease (IFD) leads to increased mortality, morbidity, and costs of treatment in patients with immunosuppressive conditions. The definitive diagnosis of IFD relies on the isolation of the causative fungal agents through microscopy, culture, or nucleic acid testing in tissue samples obtained from the sites of the disease. Biopsy is not always feasible or safe to be undertaken in immunocompromised hosts at risk of IFD. Noninvasive diagnostic techniques are, therefore, needed for the diagnosis and treatment response assessment of IFD. The available techniques that identify fungal-specific antigens in biological samples for diagnosing IFD have variable sensitivity and specificity. They also have limited utility in response assessment. Imaging has, therefore, been applied for the noninvasive detection of IFD. Morphologic imaging with computed tomography (CT) and magnetic resonance imaging (MRI) is the most applied technique. These techniques are neither sufficiently sensitive nor specific for the early diagnosis of IFD. Morphologic changes evaluated by CT and MRI occur later in the disease course and during recovery after successful treatment. These modalities may, therefore, not be ideal for early diagnosis and early response to therapy determination. Radionuclide imaging allows for targeting the host response to pathogenic fungi or specific structures of the pathogen itself. This makes radionuclide imaging techniques suitable for the early diagnosis and treatment response assessment of IFD. In this review, we aimed to discuss the interplay of host immunity, immunosuppression, and the occurrence of IFD. We also discuss the currently available radionuclide probes that have been evaluated in preclinical and clinical studies for their ability to detect IFD.
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Pfister J, Petrik M, Bendova K, Matuszczak B, Binder U, Misslinger M, Kühbacher A, Gsaller F, Haas H, Decristoforo C. Antifungal Siderophore Conjugates for Theranostic Applications in Invasive Pulmonary Aspergillosis Using Low-Molecular TAFC Scaffolds. J Fungi (Basel) 2021; 7:558. [PMID: 34356941 PMCID: PMC8304796 DOI: 10.3390/jof7070558] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/08/2021] [Accepted: 07/12/2021] [Indexed: 12/14/2022] Open
Abstract
Invasive pulmonary aspergillosis (IPA) is a life-threatening form of fungal infection, primarily in immunocompromised patients and associated with significant mortality. Diagnostic procedures are often invasive and/or time consuming and existing antifungals can be constrained by dose-limiting toxicity and drug interaction. In this study, we modified triacetylfusarinine C (TAFC), the main siderophore produced by the opportunistic pathogen Aspergillus fumigatus (A. fumigatus), with antifungal molecules to perform antifungal susceptibility tests and molecular imaging. A variation of small organic molecules (eflornithine, fludioxonil, thiomersal, fluoroorotic acid (FOA), cyanine 5 (Cy5) with antifungal activity were coupled to diacetylfusarinine C (DAFC), resulting in a "Trojan horse" to deliver antifungal compounds specifically into A. fumigatus hyphae by the major facilitator transporter MirB. Radioactive labeling with gallium-68 allowed us to perform in vitro characterization (distribution coefficient, stability, uptake assay) as well as biodistribution experiments and PET/CT imaging in an IPA rat infection model. Compounds chelated with stable gallium were used for antifungal susceptibility tests. [Ga]DAFC-fludioxonil, -FOA, and -Cy5 revealed a MirB-dependent active uptake with fungal growth inhibition at 16 µg/mL after 24 h. Visualization of an A. fumigatus infection in lungs of a rat was possible with gallium-68-labeled compounds using PET/CT. Heterogeneous biodistribution patterns revealed the immense influence of the antifungal moiety conjugated to DAFC. Overall, novel antifungal siderophore conjugates with promising fungal growth inhibition and the possibility to perform PET imaging combine both therapeutic and diagnostic potential in a theranostic compound for IPA caused by A. fumigatus.
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Affiliation(s)
- Joachim Pfister
- Department of Nuclear Medicine, Medical University Innsbruck, A-6020 Innsbruck, Austria;
| | - Milos Petrik
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, 77200 Olomouc, Czech Republic; (M.P.); (K.B.)
| | - Katerina Bendova
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University Olomouc, 77200 Olomouc, Czech Republic; (M.P.); (K.B.)
| | - Barbara Matuszczak
- Institute of Pharmacy/Pharmaceutical Chemistry, University of Innsbruck, A-6020 Innsbruck, Austria;
| | - Ulrike Binder
- Institute of Hygiene & Medical Microbiology, Medical University of Innsbruck, A-6020 Innsbruck, Austria;
| | - Matthias Misslinger
- Institute of Molecular Biology, Medical University of Innsbruck, A-6020 Innsbruck, Austria; (M.M.); (A.K.); (F.G.); (H.H.)
| | - Alexander Kühbacher
- Institute of Molecular Biology, Medical University of Innsbruck, A-6020 Innsbruck, Austria; (M.M.); (A.K.); (F.G.); (H.H.)
| | - Fabio Gsaller
- Institute of Molecular Biology, Medical University of Innsbruck, A-6020 Innsbruck, Austria; (M.M.); (A.K.); (F.G.); (H.H.)
| | - Hubertus Haas
- Institute of Molecular Biology, Medical University of Innsbruck, A-6020 Innsbruck, Austria; (M.M.); (A.K.); (F.G.); (H.H.)
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, A-6020 Innsbruck, Austria;
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Ankrah AO, Sathekge MM, Dierckx RAJO, Glaudemans AWJM. Radionuclide Imaging of Fungal Infections and Correlation with the Host Defense Response. J Fungi (Basel) 2021; 7:jof7060407. [PMID: 34067410 PMCID: PMC8224611 DOI: 10.3390/jof7060407] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 05/10/2021] [Accepted: 05/21/2021] [Indexed: 12/19/2022] Open
Abstract
The human response to invading fungi includes a series of events that detect, kill, or clear the fungi. If the metabolic host response is unable to eliminate the fungi, an infection ensues. Some of the host response’s metabolic events to fungi can be imaged with molecules labelled with radionuclides. Several important clinical applications have been found with radiolabelled biomolecules of inflammation. 18F-fluorodeoxyglucose is the tracer that has been most widely investigated in the host defence of fungi. This tracer has added value in the early detection of infection, in staging and visualising dissemination of infection, and in monitoring antifungal treatment. Radiolabelled antimicrobial peptides showed promising results, but large prospective studies in fungal infection are lacking. Other tracers have also been used in imaging events of the host response, such as the migration of white blood cells at sites of infection, nutritional immunity in iron metabolism, and radiolabelled monoclonal antibodies. Many tracers are still at the preclinical stage. Some tracers require further studies before translation into clinical use. The application of therapeutic radionuclides offers a very promising clinical application of these tracers in managing drug-resistant fungi.
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Affiliation(s)
- Alfred O. Ankrah
- National Centre for Radiotherapy Oncology and Nuclear Medicine, Korle Bu Teaching Hospital, Accra GA-222 7974, Ghana;
- Department of Nuclear Medicine, University of Pretoria, Steve Biko Academic Hospital, Pretoria 0001, South Africa;
- Medical Imaging Center, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands;
| | - Mike M. Sathekge
- Department of Nuclear Medicine, University of Pretoria, Steve Biko Academic Hospital, Pretoria 0001, South Africa;
| | - Rudi A. J. O. Dierckx
- Medical Imaging Center, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands;
| | - Andor W. J. M. Glaudemans
- Medical Imaging Center, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands;
- Correspondence:
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20
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Synthesis and Evaluation of Novel Norfloxacin Isonitrile 99mTc Complexes as Potential Bacterial Infection Imaging Agents. Pharmaceutics 2021; 13:pharmaceutics13040518. [PMID: 33918583 PMCID: PMC8069222 DOI: 10.3390/pharmaceutics13040518] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 11/17/2022] Open
Abstract
To develop potential technetium-99m single-photon emission computed tomography (SPECT) imaging agents for bacterial infection imaging, the novel norfloxacin isonitrile derivatives CN4NF and CN5NF were synthesized and radiolabeled with a [99mTc][Tc(I)]+ core to obtain [99mTc]Tc-CN4NF and [99mTc]Tc-CN5NF. These compounds were produced in high radiolabeling yields and showed hydrophilicity and good stability in vitro. The bacterial binding assay indicated that [99mTc]Tc-CN4NF and [99mTc]Tc-CN5NF were specific to bacteria. Compared with [99mTc]Tc-CN4NF, biodistribution studies of [99mTc]Tc-CN5NF showed a higher uptake in bacteria-infected tissues than in turpentine-induced abscesses, indicating that [99mTc]Tc-CN5NF could distinguish bacterial infection from sterile inflammation. In addition, [99mTc]Tc-CN5NF had higher abscess/blood and abscess/muscle ratios. SPECT image of [99mTc]Tc-CN5NF showed that there was a clear accumulation in the infection site, suggesting that it could be a potential bacterial infection imaging radiotracer.
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21
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Henneberg S, Hasenberg A, Maurer A, Neumann F, Bornemann L, Gonzalez-Menendez I, Kraus A, Hasenberg M, Thornton CR, Pichler BJ, Gunzer M, Beziere N. Antibody-guided in vivo imaging of Aspergillus fumigatus lung infections during antifungal azole treatment. Nat Commun 2021; 12:1707. [PMID: 33731708 PMCID: PMC7969596 DOI: 10.1038/s41467-021-21965-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 02/16/2021] [Indexed: 12/23/2022] Open
Abstract
Invasive pulmonary aspergillosis (IPA) is a life-threatening lung disease of immunocompromised humans, caused by the opportunistic fungal pathogen Aspergillus fumigatus. Inadequacies in current diagnostic procedures mean that early diagnosis of the disease, critical to patient survival, remains a major clinical challenge, and is leading to the empiric use of antifungal drugs and emergence of azole resistance. A non-invasive procedure that allows both unambiguous detection of IPA and its response to azole treatment is therefore needed. Here, we show that a humanised Aspergillus-specific monoclonal antibody, dual labelled with a radionuclide and fluorophore, can be used in immunoPET/MRI in vivo in a neutropenic mouse model and 3D light sheet fluorescence microscopy ex vivo in the infected mouse lungs to quantify early A. fumigatus lung infections and to monitor the efficacy of azole therapy. Our antibody-guided approach reveals that early drug intervention is critical to prevent complete invasion of the lungs by the fungus, and demonstrates the power of molecular imaging as a non-invasive procedure for tracking IPA in vivo. Invasive pulmonary aspergillosis is a life-threatening fungal lung disease devoid of specific rapid diagnosis and with limited therapeutic options. Here, the authors show how state-of-the-art imaging approaches can enable specific diagnosis and therapy monitoring of this infection.
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Affiliation(s)
- Sophie Henneberg
- Institute for Experimental Immunology and Imaging, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Anja Hasenberg
- Institute for Experimental Immunology and Imaging, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Andreas Maurer
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tübingen, Germany
| | - Franziska Neumann
- Institute for Experimental Immunology and Imaging, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Lea Bornemann
- Institute for Experimental Immunology and Imaging, University Hospital, University of Duisburg-Essen, Essen, Germany
| | | | - Andreas Kraus
- Institute for Experimental Immunology and Imaging, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Mike Hasenberg
- Institute for Experimental Immunology and Imaging, University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Christopher R Thornton
- ISCA Diagnostics Ltd. and Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Bernd J Pichler
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tübingen, Germany
| | - Matthias Gunzer
- Institute for Experimental Immunology and Imaging, University Hospital, University of Duisburg-Essen, Essen, Germany. .,Leibniz-Institut für Analytische Wissenschaften ISAS -e.V, Dortmund, Germany.
| | - Nicolas Beziere
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, Tübingen, Germany.
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22
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Development of a platform for the production of multiple modal chelating and imaging agents using desferrioxamine and bovine albumin as a model. CHEMICAL PAPERS 2021. [DOI: 10.1007/s11696-020-01374-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Swayambhu G, Bruno M, Gulick AM, Pfeifer BA. Siderophore natural products as pharmaceutical agents. Curr Opin Biotechnol 2021; 69:242-251. [PMID: 33640597 DOI: 10.1016/j.copbio.2021.01.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 01/09/2021] [Accepted: 01/25/2021] [Indexed: 11/27/2022]
Abstract
Siderophore natural products are characterized by an ability to tightly chelate metals. The origins of such compounds are often pathogenic microbes utilizing siderophores as virulence factors during host infection. The mechanism for siderophore formation typically involves the activity of nonribosomal peptide synthetases producing compounds across functional group classifications that include catecholate, phenolate, hydroxamate, and mixed categories. Though siderophore production has been a hallmark of pathogenicity, the evolutionarily-optimized binding abilities of siderophores suggest the possibility of re-directing the compounds towards alternative beneficial applications. In this mini-review, we will first describe siderophore formation origins before discussing alternative applications as pharmaceutical products. In so doing, we will cover examples and applications that include reducing metal overload, targeted antibiotic delivery, cancer treatment, vaccine development, and diagnostics. Included in this analysis will be a discussion on the native production hosts of siderophores and prospects for improvement in compound access through the adoption of heterologous biosynthesis.
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Affiliation(s)
- Girish Swayambhu
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Michael Bruno
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Andrew M Gulick
- Department of Structural Biology, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Blaine A Pfeifer
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States.
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Freeman Weiss Z, Leon A, Koo S. The Evolving Landscape of Fungal Diagnostics, Current and Emerging Microbiological Approaches. J Fungi (Basel) 2021; 7:jof7020127. [PMID: 33572400 PMCID: PMC7916227 DOI: 10.3390/jof7020127] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/27/2021] [Accepted: 02/04/2021] [Indexed: 12/17/2022] Open
Abstract
Invasive fungal infections are increasingly recognized in immunocompromised hosts. Current diagnostic techniques are limited by low sensitivity and prolonged turnaround times. We review emerging diagnostic technologies and platforms for diagnosing the clinically invasive disease caused by Candida, Aspergillus, and Mucorales.
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Affiliation(s)
- Zoe Freeman Weiss
- Brigham and Women’s Hospital, Division of Infectious Diseases, Boston, MA 02115, USA; (A.L.); (S.K.)
- Massachusetts General Hospital, Division of Infectious Diseases, Boston, MA 02115, USA
- Correspondence:
| | - Armando Leon
- Brigham and Women’s Hospital, Division of Infectious Diseases, Boston, MA 02115, USA; (A.L.); (S.K.)
| | - Sophia Koo
- Brigham and Women’s Hospital, Division of Infectious Diseases, Boston, MA 02115, USA; (A.L.); (S.K.)
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25
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Pfister J, Bata R, Hubmann I, Hörmann AA, Gsaller F, Haas H, Decristoforo C. Siderophore Scaffold as Carrier for Antifungal Peptides in Therapy of Aspergillus fumigatus Infections. J Fungi (Basel) 2020; 6:E367. [PMID: 33334084 PMCID: PMC7765500 DOI: 10.3390/jof6040367] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 12/26/2022] Open
Abstract
Antifungal resistance of human fungal pathogens represents an increasing challenge in modern medicine. Short antimicrobial peptides (AMP) display a promising class of antifungals with a different mode of action, but lack target specificity and metabolic stability. In this study the hexapeptide PAF26 (Ac-dArg-dLys-dLys-dTrp-dPhe-dTrp-NH2) and the three amino acid long peptide NLF (H2N-Asn-Leu-dPhe-COOH) were coupled to diacetylfusarinine C (DAFC), a derivative of the siderophore triacetylfusarinine C (TAFC) of Aspergillus fumigatus, to achieve targeted delivery for treatment of invasive aspergillosis. Conjugated compounds in various modifications were labelled with radioactive gallium-68 to perform in vitro and in vivo characterizations. LogD, serum stability, uptake- growth promotion- and minimal inhibitory concentration assays were performed, as well as in vivo stability tests and biodistribution in BALB/c mice. Uptake and growth assays revealed specific internalization of the siderophore conjugates by A. fumigatus. They showed a high stability in human serum and also in the blood of BALB/c mice but metabolites in urine, probably due to degradation in the kidneys. Only PAF26 showed growth inhibition at 8 µg/ml which was lost after conjugation to DAFC. Despite their lacking antifungal activity conjugates based on a siderophore scaffold have a potential to provide the basis for a new class of antifungals, which allow the combination of imaging by using PET/CT with targeted treatment, thereby opening a theranostic approach for personalized therapy.
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Affiliation(s)
- Joachim Pfister
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria; (J.P.); (R.B.); (I.H.); (A.A.H.)
| | - Roland Bata
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria; (J.P.); (R.B.); (I.H.); (A.A.H.)
| | - Isabella Hubmann
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria; (J.P.); (R.B.); (I.H.); (A.A.H.)
| | - Anton Amadeus Hörmann
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria; (J.P.); (R.B.); (I.H.); (A.A.H.)
| | - Fabio Gsaller
- Institute of Molecular Biology, Medical University Innsbruck, 6020 Innsbruck, Austria; (F.G.); (H.H.)
| | - Hubertus Haas
- Institute of Molecular Biology, Medical University Innsbruck, 6020 Innsbruck, Austria; (F.G.); (H.H.)
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria; (J.P.); (R.B.); (I.H.); (A.A.H.)
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Gunzer M, Thornton CR, Beziere N. Advances in the In Vivo Molecular Imaging of Invasive Aspergillosis. J Fungi (Basel) 2020; 6:jof6040338. [PMID: 33291706 PMCID: PMC7761943 DOI: 10.3390/jof6040338] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/01/2020] [Accepted: 12/02/2020] [Indexed: 02/07/2023] Open
Abstract
Invasive pulmonary aspergillosis (IPA) is a life-threatening infection of immunocompromised patients with Aspergillus fumigatus, a ubiquitous environmental mould. While there are numerous functioning antifungal therapies, their high cost, substantial side effects and fear of overt resistance development preclude permanent prophylactic medication of risk-patients. Hence, a fast and definitive diagnosis of IPA is desirable, to quickly identify those patients that really require aggressive antimycotic treatment and to follow the course of the therapeutic intervention. However, despite decades of research into this issue, such a diagnostic procedure is still not available. Here, we discuss the array of currently available methods for IPA detection and their limits. We then show that molecular imaging using positron emission tomography (PET) combined with morphological computed tomography or magnetic imaging is highly promising to become a future non-invasive approach for IPA diagnosis and therapy monitoring, albeit still requiring thorough validation and relying on further acceptance and dissemination of the approach. Thereby, our approach using the A. fumigatus-specific humanized monoclonal antibody hJF5 labelled with 64Cu as PET-tracer has proven highly effective in pre-clinical models and hence bears high potential for human application.
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Affiliation(s)
- Matthias Gunzer
- Institute for Experimental Immunology and Imaging, University Hospital, University Duisburg-Essen, 45147 Essen, Germany
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., 44227 Dortmund, Germany
- Correspondence: (M.G.); (N.B.); Tel.: +49-201-183-6640 (M.G.); +49-7071-29-87511 (N.B.)
| | - Christopher R. Thornton
- ISCA Diagnostics Ltd. and Biosciences, College of Life & Environmental Sciences, University of Exeter, Exeter EX4 4PY, UK;
| | - Nicolas Beziere
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, 72076 Tübingen, Germany
- Correspondence: (M.G.); (N.B.); Tel.: +49-201-183-6640 (M.G.); +49-7071-29-87511 (N.B.)
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Pfister J, Lichius A, Summer D, Haas H, Kanagasundaram T, Kopka K, Decristoforo C. Live-cell imaging with Aspergillus fumigatus-specific fluorescent siderophore conjugates. Sci Rep 2020; 10:15519. [PMID: 32968138 PMCID: PMC7511942 DOI: 10.1038/s41598-020-72452-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 08/04/2020] [Indexed: 12/18/2022] Open
Abstract
Live-cell imaging allows the in vivo analysis of subcellular localisation dynamics of physiological processes with high spatial-temporal resolution. However, only few fluorescent dyes have been custom-designed to facilitate species-specific live-cell imaging approaches in filamentous fungi to date. Therefore, we developed fluorescent dye conjugates based on the sophisticated iron acquisition system of Aspergillus fumigatus by chemical modification of the siderophore triacetylfusarinine C (TAFC). Various fluorophores (FITC, NBD, Ocean Blue, BODIPY 630/650, SiR, TAMRA and Cy5) were conjugated to diacetylfusarinine C (DAFC). Gallium-68 labelling enabled in vitro and in vivo characterisations. LogD, uptake assays and growth assays were performed and complemented by live-cell imaging in different Aspergillus species. Siderophore conjugates were specifically recognised by the TAFC transporter MirB and utilized as an iron source in growth assays. Fluorescence microscopy revealed uptake dynamics and differential subcellular accumulation patterns of all compounds inside fungal hyphae.[Fe]DAFC-NBD and -Ocean Blue accumulated in vacuoles, whereas [Fe]DAFC-BODIPY, -SiR and -Cy5 localised to mitochondria. [Fe]DAFC -FITC showed a uniform cytoplasmic distribution, whereas [Fe]DAFC-TAMRA was not internalised at all. Co-staining experiments with commercially available fluorescent dyes confirmed these findings. Overall, we developed a new class of fluorescent dyes that vary in intracellular fungal targeting , thereby providing novel tools for live-cell imaging applications for Aspergillus fumigatus.
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Affiliation(s)
- Joachim Pfister
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Alexander Lichius
- Department of Microbiology, University Innsbruck, Innsbruck, Austria
| | - Dominik Summer
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Hubertus Haas
- Division of Molecular Biology, Medical University Innsbruck, Innsbruck, Austria
| | - Thines Kanagasundaram
- Division of Radiopharmaceutical Chemistry, German Cancer Research Center, (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - Klaus Kopka
- Division of Radiopharmaceutical Chemistry, German Cancer Research Center, (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
- Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck, Austria.
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Petrik M, Pfister J, Misslinger M, Decristoforo C, Haas H. Siderophore-Based Molecular Imaging of Fungal and Bacterial Infections-Current Status and Future Perspectives. J Fungi (Basel) 2020; 6:E73. [PMID: 32485852 PMCID: PMC7345832 DOI: 10.3390/jof6020073] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 05/25/2020] [Accepted: 05/27/2020] [Indexed: 12/15/2022] Open
Abstract
Invasive fungal infections such as aspergillosis are life-threatening diseases mainly affecting immuno-compromised patients. The diagnosis of fungal infections is difficult, lacking specificity and sensitivity. This review covers findings on the preclinical use of siderophores for the molecular imaging of infections. Siderophores are low molecular mass chelators produced by bacteria and fungi to scavenge the essential metal iron. Replacing iron in siderophores by radionuclides such as gallium-68 allowed the targeted imaging of infection by positron emission tomography (PET). The proof of principle was the imaging of pulmonary Aspergillus fumigatus infection using [68Ga]Ga-triacetylfusarinine C. Recently, this approach was expanded to imaging of bacterial infections, i.e., with Pseudomonas aeruginosa. Moreover, the conjugation of siderophores and fluorescent dyes enabled the generation of hybrid imaging compounds, allowing the combination of PET and optical imaging. Nevertheless, the high potential of these imaging probes still awaits translation into clinics.
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Affiliation(s)
- Milos Petrik
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, 77900 Olomouc, Czech Republic;
| | - Joachim Pfister
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria;
| | - Matthias Misslinger
- Institute of Molecular Biology, Medical University Innsbruck, 6020 Innsbruck, Austria;
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria;
| | - Hubertus Haas
- Institute of Molecular Biology, Medical University Innsbruck, 6020 Innsbruck, Austria;
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