Advances in Molecular Tools and In Vivo Models for the Study of Human Fungal Pathogenesis

Pathogenic fungi represent an increasing infectious disease threat to humans, especially with an increasing challenge of antifungal drug resistance. Over the decades, numerous tools have been developed to expedite the study of pathogenicity, initiation of disease, drug resistance and host-pathogen interactions. In this review, we highlight advances that have been made in the use of molecular tools using CRISPR technologies, RNA interference and transposon targeted mutagenesis. We also discuss the use of animal models in modelling disease of human fungal pathogens, focusing on zebrafish, the silkworm, Galleria mellonella and the murine model.

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In Vitro and In Vivo Interactions of TOR Inhibitor AZD8055 and Azoles against Pathogenic Fungi

Microbiology Spectrum ◽

10.1128/spectrum.02007-21 ◽

2022 ◽

Author(s):

Yi Sun ◽

Lihua Tan ◽

Zhaoqian Yao ◽

Lujuan Gao ◽

Ji Yang ◽

...

Keyword(s):

Drug Resistance ◽

Combination Therapy ◽

Fungal Pathogens ◽

Pathogenic Fungi ◽

Valuable Alternative ◽

Clinical Challenge

Limited options of antifungals and the emergence of drug resistance in fungal pathogens has been a multifaceted clinical challenge. Combination therapy represents a valuable alternative to antifungal monotherapy.

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Transgenic expression of gallerimycin, a novel antifungal insect defensin from the greater wax moth Galleria mellonella, confers resistance to pathogenic fungi in tobacco

Biological Chemistry ◽

10.1515/bc.2006.071 ◽

2006 ◽

Vol 387 (5) ◽

pp. 549-557 ◽

Cited By ~ 50

Author(s):

Gregor Langen ◽

Jafargholi Imani ◽

Boran Altincicek ◽

Gernot Kieseritzky ◽

Karl-Heinz Kogel ◽

...

Keyword(s):

Transgenic Tobacco ◽

Fungal Pathogens ◽

Galleria Mellonella ◽

Ectopic Expression ◽

Pathogenic Fungi ◽

Transgenic Expression ◽

Greater Wax Moth ◽

Insect Defensin ◽

Wax Moth

Abstract A cDNA encoding gallerimycin, a novel antifungal peptide from the greater wax moth Galleria mellonella, was isolated from a cDNA library of genes expressed during innate immune response in the caterpillars. Upon ectopic expression of gallerimycin in tobacco, using Agrobacterium tumefaciens as a vector, gallerimycin conferred resistance to the fungal pathogens Erysiphe cichoracearum and Sclerotinia minor. Quantification of gallerimycin mRNA in transgenic tobacco by real-time PCR confirmed transgenic expression under control of the inducible mannopine synthase promoter. Leaf sap and intercellular washing fluid from transgenic tobacco inhibited in vitro germination and growth of the fungal pathogens, demonstrating that gallerimycin is secreted into intercellular spaces. The feasibility of the use of gallerimycin to counteract fungal diseases in crop plants is discussed.

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Preclinical In Vivo Models of Drug Resistance

Drug Resistance in Oncology ◽

10.1201/9781420002096-24 ◽

1997 ◽

pp. 393-410

Keyword(s):

Drug Resistance ◽

In Vivo Models

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Antibiotics Act with vB_AbaP_AGC01 Phage against Acinetobacter baumannii in Human Heat-Inactivated Plasma Blood and Galleria mellonella Models

International Journal of Molecular Sciences ◽

10.3390/ijms21124390 ◽

2020 ◽

Vol 21 (12) ◽

pp. 4390

Author(s):

Bartłomiej Grygorcewicz ◽

Marta Roszak ◽

Piotr Golec ◽

Daria Śleboda-Taront ◽

Natalia Łubowska ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Phage Therapy ◽

Galleria Mellonella ◽

Ex Vivo ◽

Bacterial Species ◽

Larval Survival ◽

Broad Host Range ◽

Phenotypic Analysis ◽

In Vivo Models

Increasing multidrug resistance has led to renewed interest in phage-based therapy. A combination of the bacteriophages and antibiotics presents a promising approach enhancing the phage therapy effectiveness. First, phage candidates for therapy should be deeply characterized. Here we characterize the bacteriophage vB_AbaP_AGC01 that poses antibacterial activity against clinical Acinetobacter baumannii strains. Moreover, besides genomic and phenotypic analysis our study aims to analyze phage–antibiotic combination effectiveness with the use of ex vivo and in vivo models. The phage AGC01 efficiently adsorbs to A. baumannii cells and possesses a bacteriolytic lifecycle resulting in high production of progeny phages (317 ± 20 PFU × cell−1). The broad host range (50.27%, 93 out of 185 strains) against A. baumannii isolates and the inability of AGC01 to infect other bacterial species show its high specificity. Genomic analysis revealed a high similarity of the AGC01 genome sequence with that of the Friunavirus genus from a subfamily of Autographivirinae. The AGC01 is able to significantly reduce the A. baumannii cell count in a human heat-inactivated plasma blood model (HIP-B), both alone and in combination with antibiotics (gentamicin (GEN), ciprofloxacin (CIP), and meropenem (MER)). The synergistic action was observed when a combination of phage treatment with CIP or MER was used. The antimicrobial activity of AGC01 and phage-antibiotic combinations was confirmed using an in vivo larva model. This study shows the greatest increase in survival of G. mellonella larvae when the combination of phage (MOI = 1) and MER was used, which increased larval survival from 35% to 77%. Hence, AGC01 represents a novel candidate for phage therapy. Additionally, our study suggests that phages and antibiotics can act synergistically for greater antimicrobial effect when used as combination therapy.

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Bioactive Compounds from Seaweed with Anti-Leukemic Activity: A Mini-Review on Carotenoids and Phlorotannins

Mini-Reviews in Medicinal Chemistry ◽

10.2174/1389557519666190311095655 ◽

2020 ◽

Vol 20 (1) ◽

pp. 39-53 ◽

Cited By ~ 1

Author(s):

Tânia P. Almeida ◽

Alice A. Ramos ◽

Joana Ferreira ◽

Amaya Azqueta ◽

Eduardo Rocha

Keyword(s):

Drug Resistance ◽

Bioactive Compounds ◽

Myeloid Leukemia ◽

Molecular Mechanisms ◽

Kinase Inhibitors ◽

First Line ◽

In Vivo Models ◽

Few Data

: Chronic Myeloid Leukemia (CML) represents 15-20% of all new cases of leukemia and is characterized by an uncontrolled proliferation of abnormal myeloid cells. Currently, the first-line of treatment involves Tyrosine Kinase Inhibitors (TKIs), which specifically inhibits the activity of the fusion protein BCR-ABL. However, resistance, mainly due to mutations, can occur. In the attempt to find more effective and less toxic therapies, several approaches are taken into consideration such as research of new anti-leukemic drugs and “combination chemotherapy” where different drugs that act by different mechanisms are used. Here, we reviewed the molecular mechanisms of CML, the main mechanisms of drug resistance and current strategies to enhance the therapeutic effect of TKIs in CML. Despite major advances in CML treatment, new, more potent anticancer drugs and with fewer side effects are needed. Marine organisms, and particularly seaweed, have a high diversity of bioactive compounds with some of them having anticancer activity in several in vitro and in vivo models. The state-of-art suggests that their use during cancer treatment may improve the outcome. We reviewed here the yet few data supporting anti-leukemic activity of some carotenoids and phlorotannins in some leukemia models. Also, strategies to overcome drug resistance are discussed, particularly the combination of conventional drugs with natural compounds.

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Role of Mediator in virulence and antifungal drug resistance in pathogenic fungi

Current Genetics ◽

10.1007/s00294-019-00932-8 ◽

2019 ◽

Vol 65 (3) ◽

pp. 621-630 ◽

Cited By ~ 2

Author(s):

Gary P. Moran ◽

Matthew Z. Anderson ◽

Lawrence C. Myers ◽

Derek J. Sullivan

Keyword(s):

Drug Resistance ◽

Pathogenic Fungi ◽

Antifungal Drug ◽

Antifungal Drug Resistance

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Virulence of the emerging pathogen, Burkholderia pseudomallei, depends upon the O-linked oligosaccharyltransferase, PglL

Future Microbiology ◽

10.2217/fmb-2019-0165 ◽

2020 ◽

Vol 15 (4) ◽

pp. 241-257

Author(s):

Samuel J Willcocks ◽

Carmen Denman ◽

Felipe Cia ◽

Elizabeth McCarthy ◽

Jon Cuccui ◽

...

Keyword(s):

Burkholderia Pseudomallei ◽

Galleria Mellonella ◽

In Vitro Assays ◽

In Vivo Models ◽

Bacterial Fitness ◽

Isogenic Mutants ◽

Type Strains ◽

Broad Role

Aim: We sought to characterize the contribution of the O-OTase, PglL, to virulence in two Burkholderia spp. by comparing isogenic mutants in Burkholderia pseudomallei with the related species, Burkholderia thailandensis. Materials & methods: We utilized an array of in vitro assays in addition to Galleria mellonella and murine in vivo models to assess virulence of the mutant and wild-type strains in each Burkholderia species. Results: We found that pglL contributes to biofilm and twitching motility in both species. PglL uniquely affected morphology; cell invasion; intracellular motility; plaque formation and intergenus competition in B. pseudomallei. This mutant was attenuated in the murine model, and extended survival in a vaccine-challenge experiment. Conclusion: Our data support a broad role for pglL in bacterial fitness and virulence, particularly in B. pseudomallei.

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Candida tropicalis Antifungal Cross-Resistance Is Related to Different Azole Target (Erg11p) Modifications

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00477-13 ◽

2013 ◽

Vol 57 (10) ◽

pp. 4769-4781 ◽

Cited By ~ 59

Author(s):

A. Forastiero ◽

A. C. Mesa-Arango ◽

A. Alastruey-Izquierdo ◽

L. Alcazar-Fuoli ◽

L. Bernal-Martinez ◽

...

Keyword(s):

Drug Resistance ◽

Amphotericin B ◽

Candida Tropicalis ◽

Antifungal Drug ◽

Cross Resistance ◽

Clinical Samples ◽

Content Type ◽

Antifungal Drug Resistance

ABSTRACTCandida tropicalisranks between third and fourth amongCandidaspecies most commonly isolated from clinical specimens. Invasive candidiasis and candidemia are treated with amphotericin B or echinocandins as first-line therapy, with extended-spectrum triazoles as acceptable alternatives.Candida tropicalisis usually susceptible to all antifungal agents, although several azole drug-resistant clinical isolates are being reported. However,C. tropicalisresistant to amphotericin B is uncommon, and only a few strains have reliably demonstrated a high level of resistance to this agent. The resistance mechanisms operating inC. tropicalisstrains isolated from clinical samples showing resistance to azole drugs alone or with amphotericin B cross-resistance were elucidated. Antifungal drug resistance was related to mutations of the azole target (Erg11p) with or without alterations of the ergosterol biosynthesis pathway. The antifungal drug resistance shownin vitrocorrelated very well with the results obtainedin vivousing the model hostGalleria mellonella. Using this panel of strains, theG. mellonellamodel system was validated as a simple, nonmammalian minihost model that can be used to studyin vitro-in vivocorrelation of antifungals inC. tropicalis. The development inC. tropicalisof antifungal drug resistance with different mechanisms during antifungal treatment has potential clinical impact and deserves specific prospective studies.

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