
Christopher Fernandez-PradaUniversité de Montréal | UdeM
Christopher Fernandez-Prada
DVM MSc PhD
Exploring the role of extracellular vesicles in the molecular and cellular biology of drug-resistant zoonotic parasites
About
91
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Introduction
Our research program tackles global problems through local initiatives. Focused on parasitic infections and rooted in the One Health approach, this initiative leverages the power of local communities and global collaboration to advance innovative solutions.
Additional affiliations
May 2021 - present
March 2019 - September 2026
September 2016 - present
Education
June 2013 - August 2016
September 2010 - May 2013
September 2008 - September 2010
Publications
Publications (91)
Leishmaniasis constitutes the 9th largest disease burden among all infectious diseases. Control of this disease is based on a short list of chemotherapeutic agents headed by pentavalent antimonials, followed by miltefosine and amphotericin B; drugs that are far from ideal due to host toxicity, elevated cost, limited access, and high rates of drug r...
Background
Asymptomatic Leishmania infection may play an important role in the transmission of the parasite in endemic areas. At present there is no consensus on the definition of asymptomatic Leishmania infection, nor is there a safe and accessible gold standard test for its identification.
Methods
This paper presents a scoping review to summariz...
Leishmania are eukaryotic parasites that have retained the ability to produce extracellular vesicles (EVs) through evolution. To date, it has been unclear if different DNA entities could be associated with Leishmania EVs and whether these could constitute a mechanism of horizontal gene transfer (HGT). Herein, we investigate the DNA content of EVs d...
Here, we focus on Leishmania extracellular vesicles (EVs) and their DNA content, detailing a protocol for the isolation of these nanoparticles and their subsequent genomic characterization. We describe a robust and comprehensive approach for obtaining, storing, and analyzing EVs derived from cultured parasites. We detail a user-friendly bioinformat...
Background
Visceral leishmaniasis (VL) resolution depends on a wide range of factors, including the instauration of an effective treatment coupled to a functional host immune system. Patients with a depressed immune system, like the ones receiving methotrexate (MTX), are at higher risk of developing VL and refusing antileishmanial drugs. Moreover,...
The study of extracellular vesicles has become an incredibly important field of study, but the inherent heterogeneity of these vesicles continues to make their study challenging. The genetic variability and well-documented protocols for the growth and vesicle isolation from Leishmania parasites provide a unique opportunity to compare the heterogene...
Background: The rise of drug-resistant Leishmania strains presents a significant challenge in the treatment of Leishmaniasis, a neglected tropical disease. Extracellular vesicles (EVs) produced by these parasites have gained attention for their role in drug resistance and host–pathogen interactions. Methods: This study developed and applied a novel...
Domestic dogs (Canis familiaris) and wild canids, including coyotes (Canis latrans) and red foxes (Vulpes vulpes), serve as definitive hosts for Dirofilaria immitis, a parasitic nematode causing the heartworm disease. Understanding infection risks in wildlife reservoirs in relation to environmental factors is crucial for assessing exposure risk in...
Among approaches aimed at reducing Lyme disease risk in the environment, those targeting reservoirs of Borrelia burgdorferi Johnson are promising because they have the potential to reduce both the density of questing Ixodes scapularis Say (Acari: Ixodidea) ticks and the prevalence of B. burgdorferi in the tick population. In this 4-yr field study,...
The lack of effective vaccines and the development of resistance to the current treatments highlight the urgent need for new anti-leishmanials. Sphingolipid metabolism has been proposed as a promising source of Leishmania-specific targets as these lipids are key structural components of the eukaryotic plasma membrane and are involved in distinct ce...
Leishmania spp. are zoonotic parasites transmitted by phlebotomine sand flies, including those of the Lutzomyia genus, which can cause leishmaniases in both humans and dogs. Lutzomyia spp. are established in many countries in South and Central America and some areas of the southern United States, with suspected potential of these vectors to undergo...
Echinococcus spp. is an emerging zoonotic parasite of high concern. In Canada, an increase in the number of human and animal cases diagnosed has been reported, but information regarding the parasite’s distribution in wildlife reservoir remains limited. A cross-sectional study was conducted to estimate the prevalence of wild canids infected with Ech...
Parasites of the genus Leishmania pose a global health threat with limited treatment options. New drugs are urgently needed, and genomic screens have the potential to accelerate target discovery, mode of action, and resistance mechanisms against these new drugs. We describe here our effort in developing a genome-wide CRISPR-Cas9 screen in Leishmani...
Wild animals are infected with a large diversity and abundance of parasites that can affect their behavior, growth, body condition, and ultimately their survival. Although the adverse effects of parasites and the mechanisms involved in the interactions between a host and its parasites are generally well studied, much less is known about the additiv...
The protozoan parasites Plasmodium falciparum , Leishmania spp . and Trypanosoma cruzi continue to exert a significant toll on the disease landscape of the human population in sub‐Saharan Africa and Latin America. Control measures have helped reduce the burden of their respective diseases—malaria, leishmaniasis and Chagas disease—in endemic regions...
Climate change may modify species distribution to higher latitudes, resulting in potential changes of parasite diversity and transmission dynamics in areas where animals might not be locally adapted to these new parasite species. In addition, climate change may increase the frequency and severity of infestations of parasites that are already presen...
Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their
cell of origin and change the functions and phenotypes of other cells. These features
indicate strong biomarker and therapeutic potential and have generated broad interest,
as evidenced by the steady year-on-year increase in the numbers of scientific publicati...
Parasites are responsible for the most neglected tropical diseases, affecting over a billion people worldwide (WHO, 2015) and accounting for billions of cases a year and responsible for several millions of deaths. Research on extracellular vesicles (EVs) has increased in recent years and demonstrated that EVs shed by pathogenic parasites interact w...
Assessment of structure–activity relationships for anti-protozoan activity revealed a strategy for preparing potent anisomycin derivatives with reduced host toxicity. Thirteen anisomycin analogs were synthesized by modifying the alcohol, amine, and aromatic functional groups. Examination of anti-protozoal activity against various strains of Leishma...
The COVID-19 pandemic and containment measures will likely have a detrimental impact on immunosuppressed individuals' lifestyle behaviours. Increasing evidence suggests that pet ownership is positively associated with healthier lifestyle. Yet, no study has investigated the potential benefits of pet ownership on lifestyle behaviours of immunosuppres...
Extracellular vesicles (EVs) contribute to intercellular communication through the transfer
of their rich cargo to recipient cells. The EVs produced by LPS-stimulated neutrophils from healthy humans and horses increase airway smooth muscle (ASM) proliferation, but the roles of neutrophil EVs in asthma are largely unexplored. The aim of this study w...
Visceral leishmaniasis (VL), caused by Leishmania infantum, is an oft-fatal neglected tropical disease. In the absence of an effective vaccine, the control of leishmaniasis relies exclusively on chemotherapy. Due to the lack of established molecular/genetic markers denoting parasite resistance, clinical treatment failure is often used as an indicat...
Contexte
Echinococcus spp., dont E. multilocularis, sont des parasites zoonotiques transmis par des canidés sauvages qui connaissent actuellement une émergence. Étant donné qu'ils peuvent causer des lésions sévères et de la mortalité en l'absence de traitement, la découverte récente du premier cas humain d'infection à E. multilocularis au Québec so...
In this case series, clinical investigations were pursued during a Synhimantus nasuta infection in a lorikeet (Trichoglossus spp.) flock outbreak situation to better describe and document clinical presentations. In 11 lorikeets suspected to be infected with Synhimantus based on at least one abnormal finding on their physical examination (lethargy,...
The selection of Leishmania hybrids in axenic culture was considered rare until recently, when Louradour and Ferreira et al., demonstrated
that induced DNA damage facilitates genetic exchange, resulting in
full genome tetraploid progenies in vitro. Meiosis-related gene homologues HAP2, GEX1, and RAD51 were found to be involved, opening
new avenues...
Background
The evolution of drug resistance is one of the biggest challenges in leishmaniasis and has prompted the need for new antileishmanial drugs. Repurposing of approved drugs is a faster and very attractive strategy that is gaining supporters worldwide. Different anticancer topoisomerase 1B (TOP1B) inhibitors have shown strong antileishmanial...
Cats that spend time outdoors and dogs are particularly at risk of exposure to ticks and the pathogens they transmit. A retrospective study on data collected through passive tick surveillance was conducted to estimate the risk of exposure to tick-borne pathogens in cats and dogs bitten by blacklegged ticks (Ixodes scapularis) in the province of Que...
Extracellular vesicles (EVs) are small, membrane-bound “delivery trucks” that are present in the extracellular environment, including biological fluids. EVs are capable of inducing changes in the physiological status of neighboring cells through the transfer of key macromolecules, and are thought to play a role in a number of pathological processes...
The almiramide N-methylated lipopeptides exhibit promising activity against trypanoso-matid parasites. A structure-activity relationship study has been performed to examine the influences of N-methylation and conformation on activity against various strains of leishmaniasis proto-zoan and on cytotoxicity. The synthesis and biological analysis of tw...
Background
The evolution of drug resistance is one of the biggest challenges in leishmaniasis and has prompted the need for new antileishmanial drugs. Repurposing of approved drugs is a faster and very attractive strategy that is gaining supporters worldwide. Different anticancer topoisomerase 1B (TOP1B) inhibitors have shown strong antileishmanial...
Leishmaniasis is a protozoan disease, which occurs in 12 to 15 million people worldwide and infects greater than 1 million new cases annually. The limitations in availability of effective drugs and the rise of drug resistant strains has created an urgent need for new anti-leishmanial therapy. In the light of the limitations of contemporary leishman...
Trypanosoma cruzi, Trypanosoma brucei and Leishmania (Trypanosomatidae: Kinetoplastida) are parasitic protozoan causing Chagas disease, African Trypanosomiasis and Leishmaniases worldwide. They are vector borne diseases transmitted by triatomine bugs, Tsetse fly, and sand flies, respectively. Those diseases cause enormous economic losses and morbid...
A mixed breed dog rescued from Morocco was presented at a Quebec veterinary practice for facial lesions. Leishmaniosis, an exotic disease caused by the zoonotic protozoan Leishmania infantum, was suspected. Genomic DNA extraction from blood samples and polymerase chain reaction (PCR) were used to confirm L. infantum parasitemia. Parasites were succ...
Leishmaniasis (Leishmania species), sleeping sickness (Trypanosoma brucei), and Chagas disease (Trypanosoma cruzi) are devastating and globally spread diseases caused by trypanosomatid parasites. At present, drugs for treating trypanosomatid diseases are far from ideal due to host toxicity, elevated cost, limited access, and increasing rates of dru...
Control of both human and canine leishmaniasis is based on a very short list of chemotherapeutic agents, headed by antimonial derivatives (Sb). The utility of these molecules is severely threatened by high rates of drug resistance. The ABC transporter MRPA is one of the few key Sb resistance proteins described to date, whose role in detoxification...
The primary aim of this work was to isolate common bovine digestive tract parasites in recycled manure bedding (RMS), as well as to determine the ability of current RMS preparation procedures to eliminate these pathogens. Other objectives were to assess whether any of the aforementioned parasites could be retrieved in bulk milk from dairies using R...
Background:
Leishmania are sandfly-transmitted protozoan parasites that harbour within the macrophages of a mammalian host and cause leishmaniasis, a serious zoonotic disease that threatens the lives of millions worldwide. Its numerous forms (cutaneous, mucocutaneous, and visceral) are currently treated with a sparse arsenal of drugs, specifically...
Leishmania is still a major cause of mortality and morbidity worldwide. Few efficient drugs are available, and resistance threatens actual treatments. In order to improve knowledge about the mode of action of current drugs and those in development, as well as to understand the mechanisms pertaining to their resistance, we recently described a sensi...
Fruits are among the main natural sources of phenolic compounds (PC). These compounds exert important antioxidant properties primarily associated with the presence of hydroxyl groups in their molecular structure. Additionally, the antibacterial effects of fruit phenolic-rich extracts or individual PC commonly found in fruits have been an emerging r...
Haemonchus contortus are gastrointestinal nematodes of the family Trichostrongylidae that naturally infect small ruminants while grazing, posing a risk to both animal health and farm profitability. Current diagnostics depend on exacting lab techniques, including manual egg counts and larval differentiation, all of which require time, effort, and sp...
Increasing drug resistance towards first line antimony-derived compounds has forced the introduction of novel therapies in leishmaniasis endemic areas including amphotericin B and miltefosine. However, their use is threatened by the emergence and spread of drug-resistant strains. In order to discover stage-dependent resistance genes, we have adapte...
For human health, leishmaniasis is among the most important protozoan diseases, superseded only by malaria. Globally, 10 to 12 million people are infected with 1.5 million new cases every year. The development of cheaper new drugs is urgently needed for this neglected disease that is developing resistance to current treatments. Chemotherapy remains...
Author Summary
Miltefosine and amphotericin B are two leading molecules in the fight against the vector-borne disease Leishmaniasis. We demonstrate here that different point mutations in a P-type ATPase could play an important role in resistance, not only to miltefosine, but also to amphotericin B. Furthermore, macrophage-infecting amastigotes that...
SNPs deduced from the sequencing of LdiAmB1000.1 and absent from the sequencing of its Ldi263WT parent.
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Characterisation of the PE species containing C19Δ in total lipid extracts from Ldi263 wt.
(A) ES-MS/MS parents of 295 m/z (C19Δ acyl fragment) in negative mode (600–1000 m/z). (B-G) are daughter ion ESI-MS/MS spectra of ions identified in S6A Fig: 716, 730, 744, 774, 788, 802 m/z respectively.
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AmB_SNPs-InCDS-NoSyn-Heterozygous.
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Graphical representation of the different mutations identified in MT for three Leishmania drug resistant strains.
The diagram includes the different conserved protein domains identified for the MT (GenBank: AAQ82704.1).
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Preliminary study for the characterization of mutant L. major Friedlin AmB1080.3.
(A) EC50 determination curves in the presence of miltefosine for LmF wt+mock (9.05 ± 0.89 μM), AmB1080.3+mock (54.84 ± 5.30 μM) and AmB1080.3+MT (4.43 ± 0.62 μM) cell lines over 72 h. (B) EC50 determination curves in the presence of amphotericin B for LmF wt+mock (0.1...
Identification of abundance changes to the membrane lipids in AmB- and MF-resistant parasites.
Negative ion ES-MS survey scans (600–1000 m/z) of total lipid extracts from Ldi263 wt (A upper panel), MF200.5 (B upper panel), AmB1000.1 (C upper panel) and AmB1000.1+MT (D upper panel). Positive ion ES-MS survey scans (600–1000 m/z) of total lipid extra...
Example of total ion chromatogram of derivatised fatty acids from lipid extracts of L. infantum 263 wild-type.
(A) Chromatogram including all the FAMES species with retention times spanning from 26.00 to 50.00 min for mid log phase parasites for each strain detailed in Table 1. (B) Magnification of the chromatogram for the identification of the spe...
Mass spectrometric analysis of phosphatidylethanolamine species containing cyclopropyl fatty acid in Leishmania infantum.
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Effect of the transfection of an episomal copy of the wild-type gene LinJ.16.1240 in the AmB1000.1 mutant background.
(A) EC50 determination curves in the presence of amphotericin B for Ldi263 wt (62.01 ± 5.00 nM), AmB1000.1 (1.97 ± 0.04 μM) and AmB1000.1+LinJ.16.1240 (1.89 ± 0.11 μM) cell lines over 72 h. (B) EC50 determination curves in the prese...
High resolution orbitrap mass spectrometry survey scans (600–1000 m/z) of total lipid extracts from Ldi263 wt; negative ion mode (A), positive ion mode (B).
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GC-MS Sterol Analysis of Leishmania strains.
TIC of chromatogram 39.50–43.50 min for (A) Ldi263, (B) MF200.5, (C) AmB1000.1, (D) AmB1000.1+MT. Numbered peaks refer to Table 4 for identification.
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Estimated ploidy for Ldi263AmB1000.1 and its WT parent (Ldi263WT).
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AmB_SNPs-InCDS-NoSyn-Homozygous.
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Significance
Gain-of-function screens using overexpression genomic libraries are powerful tools for discovering drug target/resistance genes, but several limitations make this technique less amenable to high-throughput screening. Using cosmid-based functional screening coupled to next-generation sequencing, an approach that we term Cosmid Sequencin...
The use of next generation sequencing has the power to expedite the identification of drug resistance determinants and biomarkers and was applied successfully to drug resistance studies in Leishmania. This allowed the identification of modulation in gene expression, in gene dosage alterations, changes in chromosome copy numbers and single nucleotid...