Le 29 septembre 2026 – 12h30 – IPNP RDC-Cafétéria – ou par Zoom

Sclérose en plaques : remyéliniser grâce à l’activité électrique

Pr Céline Louapre, Sorbonne Université, Hôpital Pitié-Salpétrière

Dr Maria Cecilia Angulo, CNRS, INSERM U1266 Institut de Psychiatrie et Neurosciences de Paris, Université Paris Cité

Les 12h30 de la recherche offre un espace d’échanges et de rencontres entre cliniciens et chercheurs autour de thématiques formant autant de priorités et d’axes possibles de recherche pour le GHU Paris et L’Institut Neurosciences Cognition. L’objectif est la mise en place, in fine, de nouveaux axes de recherche translationnelle. A chaque session, un professionnel présentera la thématique pendant 20 minutes, suivie de 40 minutes d’échanges avec les participants.

Cet évènement sera coanimé par Nicolas Panayotis, chercheur au SPPIN, et Diana Zala, chercheuse à l’IPNP.

Suivez ici le lien pour l’inscription.

The post 29 sept. 2026 -Céline Louarpe et Maria Cécillia Angulo – Sclérose en plaques : remyéliniser grâce à l’activité électrique first appeared on SPPIN - CNRS UMR 8003.

We are pleased to announce the opening of registrations for NeuralNet 2026 Paris (Nov. 25th-27th, Odéon Campus of Université Paris Cité, 75006 Paris, France)

The program will explore four broad themes — Neural Codes & Representations, Perception in Context, Learning, Memory & Adaptation, and Brain States & Network Dynamics — bringing together leading researchers working across systems and computational neuroscience. We also encourage the submission of contributed talks and posters. 

Participants are invited to join the famous spike sorting mini-school before the conference (23-25 November). The mini-school is free of charge but registration is required.

More information & registration

We look forward to receiving your contributions and to welcoming you to Paris in November for three days of exciting science, discussion, and networking with the Systems and Computational Neuroscience community.

The post SPPIN and CNRS are organizing NeuralNet 2026 in Paris on Nov. 25-27! first appeared on SPPIN - CNRS UMR 8003.

SPPIN’s seminar series spring-summer 2026, 6 jully 2026 11h00, SPPIN common room, 3rd floor, E368

ROCS – Label free imaging at 160 nm spatial and 10 ms temporal resolution

Rotating coherent scattering (ROCS) microscopy is a label-free optical imaging technique developed in our lab. It is based on coherent elastic backscattering of an obliquely incident, collimated laser beam that rotates azimuthally around the optical axis. The method can be used to image both biological cells and sub-wavelength particles. Under highly oblique illumination, the achievable spatial resolution approaches nearly twice that obtained with conventional normal illumination. During the rotation within the camera exposure time, intensity images corresponding to different illumination directions are integrated by the camera. Due to significantly lower laser powers menus in fluorescence microscopy, is excellently suited for live cell imaging. I will present and discuss basic concepts of coherent and incoherent superresolution imaging as well as recent results about binding of virus-like particles to cells and enabling material specificity in ROCS.

Please contact Martin Oheim if you want to make an appointment with Anne Sentenac

The post 6 jully 2026 – Alexander ROHRBACH – ROCS – Label free imaging at 160 nm spatial and 10 ms temporal resolution first appeared on SPPIN - CNRS UMR 8003.

SPPIN’s seminar series winter-spring 2026, wednesday 11 March 2026, 1h00, SPPIN common room, 3rd floor, E368

RIM (super-resolution) random fluorescence microscopy

Fluorescence microscopy plays a crucial role in biology due to its ability to provide functional images of living samples. Numerous techniques have been proposed in the last twenty years to improve its resolution beyond the 300 nm usually obtained with standard microscopes. Among them, the best compromise in terms of resolution and adaptation to live imaging is Structured Illumination Microscopy (SIM) in which several images of the sample are recorded under different patterned illuminations. SIM can use periodic illuminations as is periodic-SIM or focused spots as in Image Scanning Microscopy (ISM). Recently, we have developed an alternative to SIM called Random Illumination Microscopy (RIM) in which the illuminations are random speckles obtained by passing a laser beam through a diffuser. The major advantage of RIM compared to periodic-SIM and ISM is that it is insensitive to aberrations and scattering on the illumination side. It is thus more adapted to the imaging of aberrating samples. In my talk, I will present the general principles of super-resolved microscopy using structured illuminations and develop the RIM approach.

Please contact Marc Guillon if you want to make an appointment with Anne Sentenac

The post 11 March 2026 – Anne SENTENAC – RIM (super-resolution) random fluorescence microscopy first appeared on SPPIN - CNRS UMR 8003.

SPPIN’s seminar series winter-spring 2026, Monday, 23 February, 2026, 11h00, SPPIN common room, 3rd floor, E368

Going with the flow: how cell membrane tension dynamics impact cellular processes from bacteria to neurons

The plasma membrane receives and responds to mechanical signals, arising from cytoskeleton activity, membrane trafficking, and external forces such as shear flow in endothelia, or mechanical stretch in tissues. Such pushing and pulling cause changes in plasma membrane tension, which is important for development, signaling, immune response, and axon branching, among others.

Mechanosensitive channels respond to local changes in membrane tension and transmit this mechanical information across the PM. But mechanical information is also transmitted within the plane of the cell membrane in the form of membrane tension and flow. This transmission can be long range, and dynamically regulated. I will present examples we have studies across domains of life in which membrane tension and flow dynamics play a critical role: (1) membrane fission in bacteria, (2) exo-endocytosis coupling in neurons and endocrine cells, and (3) B-cell responses to antigen encounter.

PLEASE CONTACT Martin Oheim if you want to arrange a meeting with Erdem or sign up for lunch.

The post 23 February 2026 – Erdem KARATEKIN – Going with the flow: how cell membrane tension dynamics impact cellular processes from bacteria to neurons first appeared on SPPIN - CNRS UMR 8003.

SPPIN’s webinar 2025, 27 November, 2025 at 11h, SPPIN common room, 3rd floor, E368

Electrical embryogenesis and biomechanics of the second brain

Enteric neural crest cells colonize the gut rostro-caudally in early embryogenesis to give rise to the enteric nervous system, the “second brain”. Migration defects cause colonic aganglionosis at birth, a pathology known as Hirschsprung disease. Using a mouse expressing GCaMP in neural crest cells, we discovered that enteric neural crest cells display spontaneous calcium activity, that is dependent on the vasoconstrictor peptide endothelin 3 and its receptor EDNRB, and is generated by the opening of chloride and T-type calcium channels. We found that Ca2+ activity is necessary for colonization of the intestine, and that it promotes migration by generating cell-matrix contractile force. We conclude that neural crest cells can be viewed, at least in the gut, as tiny muscles that contract and crawl in response to vasoconstrictor peptides. In the second part of my talk, I will present results on the biomechanical properties of the adult enteric nervous system, which we have recently found to be 10 times stiffer than brain (central nervous system) tissue.

Please contact Clément Ricard if you want to make an appointment with Nicolas Chevalier

The post 27 November, 2025 – Nicolas CHEVALIER – Electrical embryogenesis and biomechanics of the second brain first appeared on SPPIN - CNRS UMR 8003.

SPPIN’s webinar 2025, 7 November, 2025 at 10h, SPPIN common room, 3rd floor, E368

How photonics enables higher integration density and cost efficiency for biomedical applications

The integration of optics into biomedical applications has revolutionized various fields such as molecular diagnostics, DNA sequencing, and cellular analysis. Imec, a leading research and innovation hub in nanoelectronics and digital technologies, has been at the forefront of developing chip-level integration of optical functionalities – integrated photonics – to enable higher integration density, allowing for more data per area, per time and thus true innovative biomedical solutions. Also, it allows for cost reduction because of wafer-level production, reduced manual assembly and reduced alignment of discrete optical components.

Imec’s integrated photonics platform encompasses a library of components and even includes integrated III-V light sources. The material platform includes both silicon and silicon nitride (SiN) photonics, broadening the scope of potential biomedical applications. The capabilities of its integrated photonics platform are illustrated by various pioneering projects spanning cytometry, biosensing, optogenetics, retinal imaging via optical coherence tomography, and photo-acoustic imaging. The multidisciplinary approach in these projects underscores the versatility and potential impact of on-chip integrated photonics in advancing biomedical sensing and imaging. Recently, the (heterogeneous) integration of active components has been making the platform even more powerful

Selected references

• Supercritical angle fluorescence characterization using spatially resolved Fourier plane spectroscopy – F James Shirley, P Neutens, R Vos… – Analytical Chemistry, 2018 – ACS Publications
• Lens-free photonic integrated circuit for sub-diffraction resolution and large field-of-view fluorescence imaging, S Vanuytsel, Q Desmeth, V Garcia-Munoz, A Stassen, Q Deng, … High-Throughput Biophotonics: Imaging, Spectroscopy, and Beyond X, PC133300K
• Van Drope lab website

The post 7 November, 2025 – Pol VAN DORPE & Finub JAMES SHIRLEY – How photonics enables higher integration density and cost efficiency for biomedical applications first appeared on SPPIN - CNRS UMR 8003.

SPPIN’s webinar 2025, 16 October at 10h, SPPIN common room, 3rd floor

Nano Bead Emitters: A Versatile Toolkit for Advanced Optical Thin Films

My seminar will introduce the Nano Bead Emitter (NBE) platform, a highly versatile toolkit for fabricating custom fluorescent thin films. Our approach uses dye-functionalized nanohydrogels to create exceptionally bright, stable, and homogeneous optical layers with a morphology dictated by the size of the precursor hydrogels. The platform’s modularity allows for the use of virtually any dye, which can be deposited or printed with high fidelity onto various substrates.

The versatility of this toolkit will be demonstrated through several applications. We created custom axial calibration standards with specifically chosen dyes to match biological uses and common excitation lines, making them ideal for calibrating a wide range of optical sectioning instruments, including TIRF and confocal microscopes. Our ability to print precise multi-dye patterns and fabricate transparent 3-D multi-layered architectures enables advanced applications, such as modeling complex optical effects and conducting energy transfer studies.

Highlighting the NBEs’ potential for biological research, I will present our latest findings on its biocompatibility, which allows for direct cell culture on NBE films and the use of the particles as internal probes. This work establishes the NBE platform as a powerful and adaptable solution for engineering advanced optical surfaces for both materials science and life science applications.

References

Modular Hydrogel-Based Nano-Bead Emitters for Bright, Homogeneous Fluorescent Thin Films and 3D Architectures, Ilya Olevsko, Maria Shahadeh, Eswaran Lakshmanan, Dmytro Ohorodniichuk, Eti Teblum, Moshe Feldberg, Leonid Weisman, Rotem Golan, Fabrice Licata, Martin Oheim, Gerardo, Byk, Adi Salomon. Advanced Optical Materials, 2025

Salomon lab website : https://www.lab-salomon.com/research-group

The post 16 October 2025 – Ilya OLEVSKO – Nano Bead Emitters: A Versatile Toolkit for Advanced Optical Thin Films first appeared on SPPIN - CNRS UMR 8003.

SPPIN’s webinar 2025, 4 September at 11h, SPPIN common room, 3rd floor

Pseudo-prions to treat neurodegenerative diseases

Alzheimer’s disease is the result of cerebral degeneration, caused by the abnormal accumulation of β-amyloid and tau proteins in the brain. For several years, the scientific community has believed that the toxicity of β-amyloid proteins is responsible for the induction of tau proteins. Currently, no therapy can satisfactorily block the progression of the disease.In Iceland, genetic studies have revealed that a mutation in a precursor of β-amyloid proteins (called the Icelandic mutation) protects against Alzheimer’s disease.

How is such protection possible? It has long been known that β-amyloid proteins behave like prions. This means that intracerebral inoculation of pathological β-amyloid proteins leads to the recruitment of normal brain proteins and the transformation of their conformation into pathological proteins, leading to an amplification of the lesions. β-amyloid proteins are called pseudo-prions. Prion proteins (or pseudo-prions) are characterized by a stemness1 effect. This means that different proteins can fold differently when inoculated intracerebrally, causing various symptoms.

We hypothesized that the β-amyloid protein with the Icelandic mutation could behave as a protective pseudo-prion. Based on this conjecture, we inoculated this mutated protein into mouse models of Alzheimer’s disease and observed that these mice retained their memory for months following the injection. In addition, these mice were protected from the appearance of tau-positive lesions and synaptic loss. What is extremely surprising is that a single administration was sufficient to trigger this protection, which lasts for several months. The study thus shows for the first time, in mice, that “pseudo-prion” amyloid beta proteins can protect the brain from the damage characteristic of Alzheimer’s disease.

This result could thus be the starting point for a new category of preventive therapies to treat people with neurodegenerative diseases at early stages and block the progression of the pathology, thanks to the injection of protective prions.

References

Célestine M, Jacquier-Sarlin M, Borel E, Petit F, Lante F, Bousset L, Hérard AS, Buisson A, Dhenain M. Transmissible long-term neuroprotective and procognitive effects of 1-42 beta-amyloid with A2T icelandic mutation in an Alzheimer’s disease mouse model. Mol Psychiatry. 2024 Jun 14. doi: 10.1038/s41380-024-02611-8. Epub ahead of print. PMID: 38871852

Dhenain lab website : https://dhns-inserm.fr/

The post 4 September 2025 – Marc DHENAIN – Pseudo-prions to treat neurodegenerative diseases first appeared on SPPIN - CNRS UMR 8003.

SPPIN’s webinar 2025, 10 June at 11h, SPPIN common room, 3rd floor

A Mechanism for Amplifying Sparse Neuromodulatory Signals in Electrically Coupled Interneuron Networks

Behavioral adaptation requires neural circuits to flexibly integrate sensory inputs with internal states. Neuromodulatory molecules, including neuropeptides, enable this flexibility by transiently altering circuit computation. However, the mechanisms by which neuromodulators reliably influence circuit function remain unclear, especially given the sparse expression of their receptors in key target neurons like interneurons. We investigate peptidergic modulation in the cerebellar cortex, focusing on golgi interneurons, the main inhibitory neurons of the input layer. Using transcriptomics and electrophysiology, we show that despite oxytocin receptor expression in only a subset of Golgi cells, nearly all are activated by oxytocin. This broad activation is mediated by electrical coupling: oxytocin-driven depolarization spreads through gap junctions, enhancing inhibitory control over granule cells. Our findings suggest that electrical coupling provides a general mechanism that reconciles sparse receptor expression with efficient and robust neuromodulation in cerebellar circuits and beyond.

The post 10 June 2025 – Stephanie RUDOLPH – A Mechanism for Amplifying Sparse Neuromodulatory Signals in Electrically Coupled Interneuron Networks first appeared on SPPIN - CNRS UMR 8003.