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Pepe, S.

Publications and source records attributed to Pepe, S..

2 recordsLinked to original sources

Human-derived cortical neurospheroids coupled to passive, high-density and 3D MEAs: a valid platform for functional tests

With the advent of human-induced pluripotent stem cells (hiPSCs) differentiation protocols, different methods to create in-vitro human-derived neuronal networks have been proposed. Although monolayer cultures represent a valid model, adding three-dimensionality would make them more representative of an in-vivo environment. Thus, human-derived neurospheroids and brain-organoids are becoming increasingly used for in-vitro disease modeling. Achieving control over the final cell composition and investigating the exhibited electrophysiological activity is still a challenge. Thence, platforms capable of measuring and characterizing the functional aspects of these samples are needed. Here, we propose a method to rapid generate neurospheroids of human origin with control over cell composition that can be used for functional investigations. We show a characterization of the electrophysiological activity exhibited by the neurospheroids by presenting for the first-time results from the main micro-electrodes arrays (MEAs) types available on the market (passive electrode, C-MOS electrodes, 3D electrodes). Neurospheroids grown in free culture and transferred on MEA exhibited functional activity that can be chemically and electrically modulated. Our results indicates that this model holds great potential for in-depth study of signal transmission to drug screening, disease modeling and offers a reproducible and stable platform for in-vitro functional testing.

bioengineering↗

Postnatal inflammation in Apoe-/- mice is associated with immune training and atherosclerosis

Background and aimsPreterm birth is associated with increased risk of cardiovascular disease (CVD). This may reflect a legacy of inflammatory exposures such as chorioamnionitis, that complicate pregnancies delivering preterm, or recurrent early-life infections, common in preterm infants. We previously reported that experimental chorioamnionitis followed by postnatal inflammation has additive and deleterious effects on atherosclerosis in Apoe-/- mice. Here, we aimed to investigate whether innate immune training is a contributory inflammatory mechanism in this murine model of atherosclerosis. MethodsBone marrow-derived macrophages and peritoneal macrophages were isolated from 13 week-old Apoe-/- mice, previously exposed to prenatal intra-amniotic (experimental choriomanionitis) and/or repeated postnatal (peritoneal) lipopolysaccharide (LPS). Innate immune responses were assessed by cytokine responses following 24-hour ex vivo stimulation with toll-like receptor (TLR) agonists (LPS, Pam3Cys), and RPMI for 24 hours. Bone marrow progenitor populations were studied using flow cytometric analysis. ResultsFollowing postnatal LPS exposure, bone marrow-derived macrophages and peritoneal macrophages produced more pro-inflammatory cytokines following TLR stimulation than those from LPS unexposed mice, characteristic of a trained phenotype. Cytokine production ex vivo correlated with atherosclerosis severity in vivo. Prenatal LPS did not affect cytokine production capacity. Combined prenatal and postnatal LPS exposure was associated with a reduction in common myeloid progenitor cells in the bone marrow. ConclusionsPostnatal inflammation results in a trained phenotype in atherosclerosis-prone mice that is not enhanced by prenatal inflammation. If analogous mechanisms occur in humans, then there may be novel early life opportunities to reduce CVD risk in infants with early life infections.

immunology↗