Biology subjects

Guillochon, E.

Publications and source records attributed to Guillochon, E..

3 recordsLinked to original sources

bioRxiv2023

Genetic profiling of Plasmodium ovale wallikeri relapses with microsatellite markers and whole-genome sequencing

Like Plasmodium vivax, both Plasmodium ovale curtisi and Plasmodium ovale wallikeri have the ability to cause relapse in humans, defined as recurring asexual parasitaemia originating from liver dormant forms subsequent to a primary infection. Here, we investigated relapse patterns in P. ovale wallikeri infections from a cohort of travelers who were exposed to the parasite in Sub-Saharan Africa and then experienced relapses after their return to France. Using a novel set of eight highly polymorphic microsatellite markers, we genotyped 15 P. ovale wallikeri relapses. For most relapses, the paired primary and relapse infections were highly genetically related (with 12 being homologous), an observation that was confirmed by whole-genome sequencing for the four relapses we further studied. This is, to our knowledge, the first genetic evidence of relapses in P. ovale spp.

microbiology↗

bioRxiv2021

Transcriptome analysis of Plasmodium falciparum isolates from Benin reveals specific gene expression associated with cerebral malaria

The host and parasitic factors leading to cerebral malaria (CM) are not yet fully elucidated and CM Plasmodium falciparum isolates transcriptome profile remains largely unknown. Based on RNA-seq data from 15 CM and 15 uncomplicated malaria (UM) children from Benin, we identified an increased ring stage signature in CM parasites. Reduced circulating time may result from a higher adherence ability of CM isolates and consistent with this hypothesis, we measured an overexpression of var genes in CM. var genes domains expression was more restricted in CM isolates compared to UM, reflecting the specific binding to receptors in host brain endothelium capillaries. However, ICAM-1 binding motif was found expressed in both CM and UM, questioning its role in PfEMP1 adhesion to ICAM-1 receptor. UM isolates increased circulation time may also be modulated by a more efficient immune response against infected erythrocytes surface proteins, which we could not demonstrate on our cohort. Identification of deregulated genes involved in adhesion, excluding variant surface antigens, also supports the hypothesis of an increased CM adhesion capacity. Finally, numerous upregulated genes involved in entry into host pathway were found, reflecting a greater erythrocytes invasion capacity of CM parasites.

genomics↗

bioRxiv2018

Genomic from Plasmodium falciparum field isolates from Benin allows the identification of PfEMP1 variants by LC-MS/MS at the patient’s level

PfEMP1 are the major protein family from parasitic origin involves in the pathophysiology of severe malaria, and PfEMP1 domain subtypes are associated with the infection outcome. In addition, PfEMP1 variability in endless and current protein repository do not reflect the immense diversity of the sequences of PfEMP1 proteins. The aim of our study was to identify the different PfEMP1 variants expressed within a patient sample by mass spectrometry. We performed a proteogenomic approach to decipher at the patients level PfEMP1 expression in different clinical settings: cerebral malaria, severe anemia and uncomplicated malaria. The combination of whole genome sequencing approach, RNAsequencing, and mass spectrometry proteomic analysis allowed to attribute PfEMP1 sequences to each sample and classify the relative expression level of PfEMP1 proteins within each sample. We predicted PfEMP1 structures using the newly identified protein sequences. We confirmed the involvement of DBL{beta} in malaria pathogenesis and observed that CIDR domains linked to ICAM-1 binding DBL{beta} domains displayed EPCR binding structure.

microbiology↗