Timely onset of delivery is a key factor in perinatal outcomes and child health. Preterm birth—birth before 37 weeks of gestation—is the leading cause of mortality in children under 5 years of age worldwide. Survivors are at high risk of neonatal complications and childhood sequelae, including neurodevelopmental disabilities and learning disorders, especially the most premature. Low- and middle-income countries account for the majority of the world's preterm births. Although many socio-demographic, nutritional, medical, obstetric, and environmental factors have been shown to increase the risk of spontaneous preterm birth, its aetiology is imperfectly understood. The duration of gestation or the risk of preterm birth are also complex traits under genetic control from both maternal and fetal genomes. To date, the molecular mechanisms that trigger labor in humans remain elusive. We and others have reconsidered the importance of the complex interactions between immune and stromal cells at the maternal-fetal interface during pregnancy and labor. It is vital to gather comprehensive information about their molecular composition and spatial context. State-of-the-art single cell methods (genomics, spatial proteomics, epigenomics) will be applied to maternal-fetal interface tissues to determine changes during labor. The current project will include i) mouse genetic studies that may identify novel genes involved in the onset of labor, and ii) human studies, taking into account ethnic differences and low- and middle-income countries context. The work proposed here will provide a detailed picture of the maternal interface—how many different subtypes there are as well as their function and interaction—which may be key to understand the onset of labor and preterm birth. This will be necessary for the identification of biomarkers and pharmacological targets for a better prediction and prevention of preterm birth.

To date, globally one out of four children is stunted and the current best- of -practice treatments are not able to correct for more than a third of the observed growth delays. The development of complementary, innovative interventions are therefore of utmost importance. In the Afribiota study we showed that stunting was associated with small intestinal bacterial overgrowth dominated by bacteria that normally reside in the oropharyngeal cavity and are associated with small intestinal inflammation and decrease lipid absorption. The oral-hygienic approach emerges as an entirely new preventive approach to tackle stunting. Therefore, our primary objective is to demonstrate by a specifically-designed clinical trial among 720 infants and their families in Bangui (Central-African Republic (CAR), that educating children and their families to implement strict and sustained rules of oral and nasopharyngeal hygiene will significantly prevent or reverse stunting; Our second objective is to investigate the oral cavity as a microbiological hub whose qualitative and quantitative alterations may impact on the future of child’s health. This will encompass fine description and monitoring of the oral microbiome assembly by and dynamics from birth, including key parameters influencing its ecological successions, like maternal and child hygiene, antibiotic use, and nutrition (including breastfeeding); Our third objective is to nucleate the conditions for the development of a global program of education to oral health in the CAR. Beyond the crucial question on how oral microbial communities expand to the gut resulting in the establishment of dysbiosis and stunting, this study will thus have a direct clinical benefit regarding both oral health and the treatment of undernutrition in Africa. The planned intervention on oral health will also allow us to assess the role of oral hygiene on other comorbidities, an area of much interest, as there are no data available on oral health in Africa.

Background: In 2017, World Health Organization reinstated snakebite envenoming to its priority list of neglected tropical diseases. In France, concern is related to the fashion of maintaining exotic snakes as pets, whereas Bothrops sp. are responsible for life-threatening envenomations in French guyanan and Martinique. Local signs include pain, edema, and soft tissue necrosis, whereas systemic effects are incoagulable blood, spontaneous bleeding, and major endothelial dysfunction. Bothrops antivenoms are the only specific treatment to counteract envenoming, whereas their clinical efficacy has been rchallenged. Specific rationale of the research program: In most cases, chosen antivenom starts hours after the snake accident; thus, tissue inflammatory process is well advanced at the time of immunotherapy. Despite potent inhibition of circulating toxins by antivenoms, Bothrops snakebite can trigger overwhelming systemic inflammatory host response (SIRS), leading to multiple organ system failure and death. Central to sterile SIRS are recognition of “sensing danger” motifs such tissue damage-associated molecular pattern molecules (DAMPs). DAMPs induce inflammation through recognition by Toll like receptors (TLRs) and NOD-like receptors (NLRs), activating transcription factors and inflammation. Hypothesis of the research program: We state that Bothrops snakebites can induce overwhelming SIRS triggered by venom-associated molecular patterns (VAMPs) and DAMPs signaling. Regarding “danger motifs”, DAMPs release from mitochondria (mtDAMPs) is of critical importance due to their ancestral microbial origin. We state that mtDAMPs may be released from either injured bitten tissues or secondary to increased cell membrane permeability of target organs in response to exposure to Bothrops venom toxins. In addition, mitochondrial dysfunction elicited by severe envenomations will disrupt fine tune regulation of innate immune response through mechanisms involving oxidative stress, cardiolipin externalization, and impaired mitophagy. Preventing mitochondrial dysfunction by mitochondria-targeted antioxidants would thus able to improve severe Bothrops envenomation. Results and discussion: Our results will depict venom components and immunorecognition neutralization by antivenoms of Bothrops sp. endemic in French oversea areas. Second, preclinical studies in Bothrops venom–treated mice will reproduce features of pathophysiological profile observed in human, such as local edema/necrosis and systemic hemorrhage. Our study will also demonstrate for the first time that Bothrops envenoming induce inflammation through signaling pathways including TLRs and NLRP3 inflammasome activation. Third, our results will demonstrate that intravenous Bothrops venom induces mtDAMPs release, thus indicating that VAMPs may directly induce DAMPs release independently of venom-induced local injuries. Translational studies in human will show that Bothrops snake venom mixtures impair mitochondrial function and induce mtDAMPs release in ex vivo human preparations of cardiac cells and artery vessel rings. Our results will show that Bothrops toxins induce mtDNA release, mitochondrial dysfunction, abnormal vasorelaxation and endothelial cell dysfunction, which are all prevented by mitochondria-targeted antioxidants. Importantly, these results will be translated into new medical practice. Pilot clinical trials in Martinique and French Guyana will be promoted to demonstrate that elamipretide, an effective mitochondria-targeted antioxidant previously approved for clinical use, improve mitochondrial dysfunction, blunt inflammation and prevent multiple organ failure in severe Bothrops envenomation. Conclusion: Overall, our efforts will identify new pharmacological mitochondrial targets that control the inflammation process in its early stage and provide new complementary treatments to traditional antivenom immunotherapy for Bothrops envenomation.

Plasmodium is the protozoan parasite responsible for malaria, first parasitic cause of death worldwide. According to the 2015 World Malaria Report, 214 million people were infected by Plasmodium in 2014, leading to 438 000 deaths out of which about 88% occurred in Africa, mainly in children under five. Among the Plasmodium genus, P. falciparum is the causative agent of the most severe type of malaria: cerebral malaria. Artemisinin-based combination therapies, first line treatment of Plasmodium falciparum malaria, are facing failures due to resistances, so new treatments based on new targets of the parasite are urgently needed. During the last few years, among the new chemical entities, which have demonstrated promising antiplasmodial properties, original quinazoline derivatives were identified. So far, the preliminary study of their in vitro biological activity did not permit to elucidate their mechanism of action, different of the currently marketed antimalarial drugs (i.e. blocking heme detoxification, mitochondrial membrane potential alteration, free radical production, and inhibition of PfDHFR). Within the aim of deciphering the mechanism of action of the hit-quinazoline compound, an “affinity chromatography on immobilized inhibitor” approach was conducted allowing the preliminary identification by mass-spectroscopy of two parasitic essential enzymes PfRab6 and PfPyrK1. In this context, the objectives of the NINTARMAL project are 1) to confirm the action of the hit-molecules on the identified target-proteins by evaluating their behavior in biochemical in vitro tests combining the pure recombinant plasmodial targets and the originally synthesized hit molecules; 2) to synthesize several new original molecular series derived from previously identified antiplasmodial quinazolines; 3) in parallel, to perform the screening of the corresponding synthesized compounds and define their biological profile for guiding the chemistry work, in order to discover and validate the most promising in vitro hits against P. falciparum; 4) a rational-guided conception of new drug candidates targeting PfRab6 and PfPyrK1 will be assisted by chemoinformatics, crystallography data, in vitro evaluations, electrochemical and pharmacokinetic studies 5) further evaluations on field isolates and artemisinin-resistant strain of P. falciparum, in vivo mice toxicity opening the way to subsequent in vivo evaluation in humanized mouse model.

Postnatal diagnosis of congenital toxoplamosis infection, caused by the parasite Toxoplasma gondii is imperative to ensure optimal medical care. Thus, the early identification of specific antibodies developed by the newborn is of crucial importance. This is a challenge because of the joint presence with maternal immunoglobulin G (IgG) in the serum of the newborn. The present proposal aims to identify newborn IgG that are specific for the pathogen. To achieve this goal, we will explore the individual signatures carried by the heavy chain of IgG and resulting from polymorphisms of several amino acids. We will use affinity purification to select specific IgG, adapted device to miniaturize these protocols and middle-down mass spectrometry for the proteogenomic characterization of these IgGs . Mapping of glycosylation of IgG will also be performed. Many scientific challenges will be overcome: (1) we will propose a workflow for the purification of pathogen-specific IgGs; (2) we will develop a proteolytic system to release the shortest discriminant sequences to identify peptide variants; (3) we will integrate the most recent updates of genomic information available in the public repository with dedicated proteomics and intermediary approaches in a proteogenomic strategy; (4) we will analyze the glycosylation profile in order to study a potential correlation with the specificity of IgG and their maternal or infant origin. We will use key samples that are already well characterized to validate our approach, and then apply it to paired samples of mothers (peripheral blood) and newborns (cord blood) derived from two existing cohorts in France and Benin focused on toxoplasmosis. The samples of interest are those taken in cases where the mother had a toxoplasmosis primary infection inducing seroconversion during pregnancy and where the newborn is suspected of having contracted the infection in utero. To be successful, the strategy will be optimized to achieve the sensitivity required to be directly compatible with the small amount of peripheral blood that can be collected from a neonate (maximum total serum volume 100 µL). This project will benefit from the expertise of complementary teams in immunological studies of congenital diseases and middle-down proteomics. It will be accompanied by three particularly adapted structures: the IRD, which coordinates the establishment of cohorts of interest, the ESPCI proteomics platform and in particular a high-resolution UVPD MS/MS mass spectrometer with a regional funding obtained in 2018, and the IPGG Labex for microfluidics. The two partners have been working together since 2011, which has been formalized by a collaborative research program between IRD and ESPCI. In the long term, this technological breakthrough will pave the way for many applications such as the diagnosis and monitoring of other congenital parasitic diseases (mainly Chagas disease), or more generally other infections of bacterial or viral origin, as well as other pathologies associated with autoimmune disorders such as insulin-dependent type 1 diabetes.