Biology subjects

Marquette, C.

Publications and source records attributed to Marquette, C..

6 recordsLinked to original sources

bioRxiv2026

Persistent cerebrovascular injury after preeclampsia in the STOX1A mouse model: implications for prokineticin signaling

Preeclampsia (PE) is a pregnancy-related hypertensive disorder associated with neurological complications that may persist beyond pregnancy. Prokineticins (PROK1 and PROK2) and their receptors (PROKR1 and PROKR2) regulate angiogenesis and inflammation and may be involved to PE-associated cerebrovascular injury. This study investigated alterations of the maternal brain prokineticin system during PE and 8 months postpartum, and assessed the consequences of prokineticin receptor inhibition using the PROKR antagonist PC1. Female WT FVB/N mice mated with transgenic males overexpressing STOX1A were used as a model of PE and received PC1 or vehicle during gestation. Circulating and regional brain PROK levels and receptor expression were assessed by ELISA and Western blotting. Long-term cerebral abnormalities were evaluated using high-resolution MRI and GFAP immunostaining. PE mice exhibited hypertension, proteinuria, reduced placental efficiency, and elevated circulating PROK1 and PROK2 levels. PC1 prevented hypertension and attenuated the elevation of circulating PROKs but did not prevent proteinuria or reduced placental efficiency. During PE, hippocampal PROK1 increased while PROK2 decreased; these changes persisted despite treatment. At 7 months postpartum, both PROKs were elevated in the cortex, and these increases were prevented by PC1. Region-specific changes in PROKR1 immunoreactivity and PROKR2 expression showed variable responses to treatment. MRI revealed hippocampal and parieto-temporal T2* hypointensities compatible with microhemorrhagic injury, post-contrast T1 abnormalities supporting blood-brain barrier disruption, and a distinct caudoputamen T1-hyperintense lesion potentially representing a nonhemorrhagic component. PC1 prevented focal cerebral lesions and associated astrocyte reactivity, whereas regional diffusion abnormalities persisted. These findings implicate prokineticin signaling in persistent PE-associated brain injury and support the potential of receptor antagonism to limit selected cerebral alterations.

neuroscience↗

bioRxiv2024

Biofabrication of spatially organized temporo-mandibular fibrocartilage assembloids

The combination of mesenchymal stem cell (MSC) spheroids and polymeric scaffolds has been actively explored for engineering organized hyaline cartilage; however, its application to other types of cartilage remains under-explored. The temporo-mandibular joint (TMJ) fibrocartilage is a highly stratified tissue whose recapitulation remains challenging. In this study, the shape and growth orientation of assembloids were controlled by seeding early mature human adipose-derived MSC spheroids into polymeric scaffolds with a dual architecture of micron-scale fibers. This results in flattened asymmetric tissues with a single-sided articular surface. Structurally, the engineered fibrocartilage mimicked the histotypical organization observed in the native human condylar fibrocartilage, notably featuring a thick fibrous zone with flattened cells. Native-like distribution of general extracellular matrix (ECM) components, including glycosaminoglycans and total collagens, and ECM-specific components, such as type I and II collagens, aggrecan core protein, and fibronectin, were observed. Collagen organization, as demonstrated by polarized light microscopy and scanning electron microscopy at the fibril level, was also found to be similar to that of native human tissue. Zonal-dependent micromechanical properties were identified in both the engineered and native tissues, although lower mechanical properties were observed in the fibrous zone of the engineered tissue. This work provides further evidence that the combination of MSC spheroids and micron-sized fiber polymeric scaffolds is a versatile approach for engineering stratified cartilage and a promising strategy for engineering biomimetic fibrocartilage grafts for TMJ reconstruction.

bioengineering↗

bioRxiv2023

REAL-TIME AT-LINE MONITORING OF INFLUENZA VIRUS IN CELL CULTURE BY A SURFACE PLASMON RESONANCE BIOSENSOR

Since the early 2000, regulation agencies have encouraged viral vaccine manufacturers to implement in-process and real-time monitoring tools in production processes. Even if more assays have been recently developed, none of the novel viral particle quantification technologies can monitor virus levels and their secretion kinetics within production vessels. Vaccine manufacturers still rely on offline cell-based infectivity assays and antigen amount quantification to monitor their processes. The present study describes the development of the first automated biosensor for at-line monitoring of influenza virus production. It involves coupling a fetuin-based SPRi quantitative biosensor with an automated sampler of culture broth and a consecutive clarification setup via an acoustic filter. The SPRi response of different viral strains produced in two distinct cell production platforms was qualified. We demonstrated that fetuin-based quantitative SPRi is a robust, potency-indicating, and universal analytical technology for quantifying bioactive influenza virus particles. It was validated with both purified and complex matrices. Finally, an influenza viral production kinetic was monitored online for three days. This novel online tool enabled the access in real-time to total bioactive viral particles from early production phases (8hpi).

bioengineering↗

bioRxiv2023

Deciphering dermal fibroblast behavior in 3D bioprinted dermis contructs

In recent years, numerous strategies have emerged to answer the growing demand for graftable tissues. Tissue engineering and in-vitro production are one of them. Among all the engineered tissues, skin is one of the most advanced. Nevertheless, biofabrication of graftable and fully functional skin substitutes is still far from being reached. Skin reconstruction, particularly dermis, necessitates cultivation and maturation for several weeks (> 3 weeks) to recover the tissues composition and functions, which prevent its transfer to clinical applications. Thus, several strategies, including 3D bioprinting, have been explored to accelerate these productions. In the present study, based on the successful application of 3D bioprinting achieved by our group for skin reconstruction in 21 days, we propose to detail the biological behaviors and maturation phases occurring in the bioprinted skin construct thanks to a descriptive approach transferred from the bioprocess field. The aim is to comprehensively characterize dermis construct maturation phases (cell proliferation and ECM secretion) to master later the interdependent and consecutive mechanisms involved in in-vitro production. Thus, standardized quantitative techniques were deployed to describe 3D bioprinted dermis proliferation and maturation phases. Then, in a second step, various parameters potentially impacting the dermis reconstruction phases were evaluated to challenge our methodology and reveal the biological behavior described (fibroblast proliferation and migration, cell death, ECM remodeling with MMP secretion). The parameters studied concern the bioprinting practice including various printed geometries, bioink formulations and cellular physiology in relation with their nutritional supplementation with selected medium additives.

bioengineering↗

bioRxiv2022

Radioactive Contamination in Feral Dogs in the Chernobyl Exclusion Zone: Population Body-Burden Survey and Implications for Human Radiation Exposure

This report describes a two-year effort to survey the internal 137Cs and external {beta}-emitter contamination present in the feral dog population near the Chernobyl nuclear power plant (ChNPP) site, and to quantify the potential for human radiation exposure from this contamination. This work was performed as an integral part of the radiation safety and control procedures of an animal welfare oriented trap-neuter-release (TNR) program. The measurement program employed handheld {beta}-sensitive probes, and a simple whole-body counter to measure internal 137Cs burden during post-surgical observation and recovery. External {beta} contamination surveys performed during intake showed that 21/288 animals had significant, removable external contamination. Measurements with the whole-body counter indicated internal 137Cs body burdens ranging from undetectable (minimum detection level [~]100 Bq/kg in 2017, [~] 30 Bq/kg in 2018) to approximately 30,000 Bq/kg. A total of 33 animals had 137Cs body-burdens above 1 kBq/kg. We observe that internal contamination levels are positively correlated with capture locations within ChNPP boundaries. The large variation in the 137Cs concentration in these animals is not well-understood, could be due to prey selection, access to human food scraps, or extended residence in highly contaminated areas. These internally-contaminated animals are unlikely to pose an exposure hazard despite their large body-burdens due to their limited exposure to humans. However, the small minority of animals with external contamination may pose a contamination hazard to workers, tourists, and others interacting with the dogs, as evidenced by total quantity of removable activity and incidents of transfer to materials used in animal capture.

zoology↗

bioRxiv2021

Passive sampling of environmental DNA in aquatic environments using 3D-printed hydroxyapatite samplers

O_LIThe study of environmental DNA released by aquatic organisms in their habitat offers a fast, non-invasive and sensitive approach to monitor their presence. Common eDNA sampling methods such as filtration and precipitation are time consuming, require human intervention and are not applicable to a wide range of habitats such as turbid waters and poorly-accessible environments. To circumvent these limitations, we propose to use the binding properties of minerals to create a passive eDNA sampler. C_LIO_LIWe have designed 3D-printed samplers made of hydroxyapatite (HAp samplers), a mineral known for its high binding affinity with DNA. The shape and the geometry of the samplers have been designed to facilitate their handling in laboratory and field. Here we describe and test the ability of HAp samplers to recover artificial DNA and eDNA. C_LIO_LIWe show that HAp samplers efficiently recover DNA and are effective even on small amounts of eDNA (<1 ng). However, we also observed large variations in the amount of DNA recovered even under controlled conditions. C_LIO_LIBy better understanding the physico-chemical interactions between DNA and the HAp sampler surface, one could improve the repeatability of the sampling process and provide an easy-to-use eDNA sampling tool for aquatic environments. C_LI

molecular biology↗