Galleria mellonella hemocytes: A novel phagocytic assay for Leishmania (Viannia) braziliensis

Tomiotto-Pellissier, Fernanda; Cataneo, Allan Henrique Depieri; Orsini, Tatiane Marcuso; Thomazelli, Ana Paula Fortes dos Santos; Dalevedo, Gabriela Alcântara; Oliveira, Admilton Gonçalves de; Panagio, Luciano Aparecido; Costa, Idessânia Nazareth; Conchon‐Costa, Ivete; Pavanelli, Wander Rogério; Almeida, Ricardo Sérgio

doi:10.1016/j.mimet.2016.10.001

Cited by 10 publications

(10 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Whilst G. mellonella larvae do not possess an adaptive immune system they do display an innate immune system similar to humans with many analogous functions including, phagocytosis of pathogens by haemocytes [17,34,52–54], a similar cell type to human macrophages and neutrophils [36]. They also produce antimicrobial peptides, complement-like proteins and reactive oxygen and nitrogen species for killing ingested pathogens, all found within the haemolymph, a biological fluid similar to mammalian blood [15,16,18].…”

Section: Discussionmentioning

confidence: 99%

Galleria mellonella - a novel infection model for the Mycobacterium tuberculosis complex

Spiropoulos

Cooley

et al. 2018

Virulence

View full text Add to dashboard Cite

Animal models have long been used in tuberculosis research to understand disease pathogenesis and to evaluate novel vaccine candidates and anti-mycobacterial drugs. However, all have limitations and there is no single animal model which mimics all the aspects of mycobacterial pathogenesis seen in humans. Importantly mice, the most commonly used model, do not normally form granulomas, the hallmark of tuberculosis infection. Thus there is an urgent need for the development of new alternative in vivo models. The insect larvae, Galleria mellonella has been increasingly used as a successful, simple, widely available and cost-effective model to study microbial infections. Here we report for the first time that G. mellonella can be used as an infection model for members of the Mycobacterium tuberculosis complex. We demonstrate a dose-response for G. mellonella survival infected with different inocula of bioluminescent Mycobacterium bovis BCG lux, and demonstrate suppression of mycobacterial luminesence over 14 days. Histopathology staining and transmission electron microscopy of infected G. mellonella phagocytic haemocytes show internalization and aggregation of M. bovis BCG lux in granuloma-like structures, and increasing accumulation of lipid bodies within M. bovis BCG lux over time, characteristic of latent tuberculosis infection. Our results demonstrate that G. mellonella can act as a surrogate host to study the pathogenesis of mycobacterial infection and shed light on host-mycobacteria interactions, including latent tuberculosis infection.

show abstract

Section: Discussionmentioning

confidence: 99%

Galleria mellonella - a novel infection model for the Mycobacterium tuberculosis complex

Spiropoulos

Cooley

et al. 2018

Virulence

View full text Add to dashboard Cite

show abstract

“…Haemocyte collection was performed as previously described [95]. Briefly, haemolymph was collected and diluted 1:10 into Insect Physiological Saline (IPS) [150 mM sodium chloride, 5 mM potassium chloride, 10 mM Tris HCl, 10 mM EDTA and 30 mM sodium citrate] with 10 mM N-ethylmaleimide (anticoagulant).…”

Section: Methodsmentioning

confidence: 99%

Generational distribution of a Candida glabrata population: Resilient old cells prevail, while younger cells dominate in the vulnerable host

et al. 2017

View full text Add to dashboard Cite

Similar to other yeasts, the human pathogen Candida glabrata ages when it undergoes asymmetric, finite cell divisions, which determines its replicative lifespan. We sought to investigate if and how aging changes resilience of C. glabrata populations in the host environment. Our data demonstrate that old C. glabrata are more resistant to hydrogen peroxide and neutrophil killing, whereas young cells adhere better to epithelial cell layers. Consequently, virulence of old compared to younger C. glabrata cells is enhanced in the Galleria mellonella infection model. Electron microscopy images of old C. glabrata cells indicate a marked increase in cell wall thickness. Comparison of transcriptomes of old and young C. glabrata cells reveals differential regulation of ergosterol and Hog pathway associated genes as well as adhesion proteins, and suggests that aging is accompanied by remodeling of the fungal cell wall. Biochemical analysis supports this conclusion as older cells exhibit a qualitatively different lipid composition, leading to the observed increased emergence of fluconazole resistance when grown in the presence of fluconazole selection pressure. Older C. glabrata cells accumulate during murine and human infection, which is statistically unlikely without very strong selection. Therefore, we tested the hypothesis that neutrophils constitute the predominant selection pressure in vivo. When we altered experimentally the selection pressure by antibody-mediated removal of neutrophils, we observed a significantly younger pathogen population in mice. Mathematical modeling confirmed that differential selection of older cells is sufficient to cause the observed demographic shift in the fungal population. Hence our data support the concept that pathogenesis is affected by the generational age distribution of the infecting C. glabrata population in a host. We conclude that replicative aging constitutes an emerging trait, which is selected by the host and may even play an unanticipated role in the transition from a commensal to a pathogen state.

show abstract

“…A phagocytic assay for scanning electron microscopy (SEM) analysis was conducted as described by Tomiotto-Pellissier et al . 40 , with modifications. Round coverslips (13 mm) treated with poly-L-lysine (Sigma Aldrich, USA) were placed in a 24-well plate.…”

Section: Methodsmentioning

confidence: 99%

Phenotypic switching in Candida tropicalis alters host-pathogen interactions in a Galleria mellonella infection model

Perini

Moralez

Almeida

et al. 2019

Sci Rep

Self Cite

View full text Add to dashboard Cite

Candida tropicalis is a human pathogen associated with high mortality rates. We have reported a switching system in C . tropicalis consisting of five morphotypes – the parental, switch variant (crepe and rough), and revertant (crepe and rough) strains, which exhibited altered virulence in a Galleria mellonella model. Here, we evaluate whether switching events may alter host-pathogen interactions by comparing the attributes of the innate responses to the various states. All switched strains induced higher melanization in G . mellonella larvae than that induced by the parental strain. The galiomicin expression was higher in the larvae infected with the crepe and rough morphotypes than that in the larvae infected with the parental strain. Hemocytes preferentially phagocytosed crepe variant cells over parental cells in vitro . In contrast, the rough variant cells were less phagocytosed than the parental strain. The hemocyte density was decreased in the larvae infected with the crepe variant compared to that in the larvae infected with the parental strain. Interestingly, larvae infected with the revertant of crepe restored the hemocyte density levels that to those observed for larvae infected with the parental strain. Most of the switched strains were more resistant to hemocyte candidacidal activity than the parental strain. These results indicate that the switch states exhibit similarities as well as important differences during infection in a G . mellonella model.

show abstract

Galleria mellonella hemocytes: A novel phagocytic assay for Leishmania (Viannia) braziliensis

Cited by 10 publications

References 23 publications

Galleria mellonella - a novel infection model for the Mycobacterium tuberculosis complex

Galleria mellonella - a novel infection model for the Mycobacterium tuberculosis complex

Generational distribution of a Candida glabrata population: Resilient old cells prevail, while younger cells dominate in the vulnerable host

Phenotypic switching in Candida tropicalis alters host-pathogen interactions in a Galleria mellonella infection model

Contact Info

Product

Resources

About