The France-BioImaging Annual Meeting 2026 came to a close after two days held on March 12-13 in Rouen. This year’s edition, centered on the theme “Multimodalities for organ and organism imaging”, brought together the community for rich scientific discussions and new perspectives for collaboration.

Through a series of insightful presentations, the event showcased the wide spectrum of imaging approaches developed within France-BioImaging, highlighting both their potential and the challenges ahead. This edition also marked the first participation of industry sponsors (F-DGSi, Inscoper, Leica Microsystems, Nikon, Thermo Fisher Scientific and Zeiss) whom we warmly thank for their valuable support.

Day 1 – Infrastructure, collaboration and emerging synergies

The morning continued with key updates from France-BioImaging, followed by an overview of the Normandie Node. Several strategic topics were then addressed, reflecting the infrastructure’s core priorities:

• strengthening collaborations between academia and industry, notably through partnership models such as the collaboration between PRIMACEN and the start-up Alga Biologics cSMARt project,
• reinforcing education and training, from master’s programs to career development initiatives supported by Euro-BioImaging,
• advancing data management and sharing, with significant progress highlighted within the FBI.data initiative and the BioImage Cloud.

The day concluded with the first scientific session dedicated to plant and invertebrate imaging. Presentations illustrated advanced 3D analysis approaches and electron microscopy applications, followed by a keynote lecture from Marie Walde (EMBRC infrastructure), who shared recent advances and challenges in imaging marine organisms.

Day 2 – Multimodal imaging across biological systems

A keynote lecture by Maxime Gauberti (FLI infrastructure) introduced innovative developments in immuno-MRI, further illustrating the power of multimodal strategies in neuroscience.

The programme then featured an industry-focused session, where partners including Inscoper, Leica Microsystems, Thermo Fisher Scientific, and Zeiss presented advanced imaging solutions and discussed current challenges in multimodal bioimaging .

In the afternoon, scientific sessions explored imaging applications across multiple organ systems. Topics included:

• muscle and cardiovascular imaging, with a focus on pathological conditions,
• lung intravital microscopy revealing immune cell dynamics,
• advanced methodologies for gastrointestinal and liver imaging, including studies on hepatic diseases and infection models.

A dynamic and collaborative community

Over the course of these two days, the Annual Meeting highlighted the diversity and excellence of imaging technologies within the France-BioImaging network, as well as the strong expertise of its platforms and R&D teams.

The event also reinforced the importance of collaboration between nodes, disciplines and industry partners, to address current and future challenges in bioimaging.

A replay of the Annual Meeting will be available soon for those who wish to revisit the sessions.

We would like to warmly thank the local organizing team for their outstanding work, as well as all our sponsors for their support in making this event a success.

The Photonic Microscopy Platform at Imagerie-Gif (France-BioImaging Île-de-France Sud node) is organizing two events to introduce its new imaging system: the Thunder Imager Cell / Spinning Disk Cicero.

A first event, Pizza Tech, will take place on March 27 (12:00–13:30). After a pizza lunch, Leica will present the new setup and its capabilities.

A Demo Week will then be organized from March 31 to April 2, during which researchers, PhD students and engineers will have the opportunity to bring their own samples and test the system.

Participants interested in attending can register by email at: plt-phot@i2bc.paris-saclay.fr

The AgroServ translational/virtual access programme is back with its fifth and final call, offering researchers working on agroecology projects access to more than 140 research services across Europe.

As Euro-BioImaging is a partner of the programme, researchers can benefit from access to advanced microscopy facilities, including the France-BioImaging facility Imagerie-Gif.

New in this call: applicants can now request access to services from a single research infrastructure if this better fits their research needs. Previously, applications had to combine services from multiple infrastructures.

This programme supports research addressing sustainable and resilient agri-food systems, including topics such as plant biology, soil, water and microorganisms. Selected projects benefit from free access to leading European research infrastructures, providing cutting-edge technologies and expertise to support agroecology research.

Deadline for applications: June 8, 2026

More information about the call and the application procedure is available here:
https://agroserv.eu/calls-and-applications/application-procedure

Short-term synaptic plasticity (STP), the rapid modulation of synaptic efficiency during closely spaced neuronal activity, has long been considered primarily presynaptic in origin. In a study published in Neuron⁽¹⁾, Daniel Choquet’s team (IINS, Neurocampus Bordeaux) demonstrates, using several advanced microscopy approaches implemented at the Bordeaux Imaging Center (France-BioImaging Bordeaux node), that postsynaptic AMPA receptor mobility plays a decisive role in this regulation.

Visualizing receptor dynamics in real time

To investigate this mechanism, researchers used primarily lattice light-sheet (LLS) microscopy, a high spatiotemporal resolution system enabling the characterization of AMPA receptor mobility at individual synapses. This approach revealed that AMPA receptors are not static but undergo lateral diffusion within the postsynaptic membrane.

By combining LLS with Fluorescence Recovery After Photobleaching (FRAP) experiments, AMPA receptor mobile fraction can be quantified. The team also used targeted 1P and 2P photo-manipulation, to demonstrate the link between potentiation or depression and receptor mobility. When AMPA receptors are immobilized, synaptic depression increases.

Super-resolution STORM microscopy was also employed to examine the static nano-organization of AMPA receptor subunits. The results show that their nanoscale organization is not altered when immobilizing AMPA by crosslinking agent. Only the mobility is affected as revealed with LLS single particle tracking.

From single synapses to neuronal networks

Finally, two-photon microscopy enabled the study of the impact of AMPA receptor mobility at the network level. The findings indicate that receptor dynamics influence collective neuronal activity and contribute to maintaining appropriate synaptic gain.

These findings establish AMPA receptor mobility as a functional component of short-term plasticity. By directly visualizing and manipulating receptor dynamics, advanced microscopy demonstrates that postsynaptic receptor motion actively shapes synaptic strength regulation.

(1) Agata Nowacka, Angela M. Getz, Hanna L. Zieger, Maxime Malivert, Diogo Bessa-Neto, Elisabete Augusto, Christelle Breillat, Sophie Daburon, Cécile Lemoigne, Sébastien Marais, Mathieu Ducros, Alexandre Favereaux, Andrew C. Penn, Richard Naud, Matthieu Sainlos, Daniel Choquet, Synapse-specific and plasticity-regulated AMPA receptor mobility tunes synaptic integration, Neuron, 2026, ISSN 0896-6273, https://doi.org/10.1016/j.neuron.2025.12.004.

Throughout the day, discussions revolved around real-life workflows in correlative microscopies, advanced light-sheet imaging, and plant imaging under physiological constraints. Correlation was approached broadly, encompassing not only light and electron microscopy, but also multi-modal strategies combining different contrast mechanisms, spatial scales and preparation conditions. Rather than focusing on individual systems, the exchanges centered on how these complementary modalities are orchestrated in practice to answer complex biological questions.

One particularly illustrative discussion concerned live imaging of plant root systems. Unlike many biological samples, plant roots are highly sensitive to gravity and grow continuously during observation. Conventional horizontal microscope configurations can therefore introduce non-physiological constraints, potentially altering the very processes under investigation. This raises the need for vertical imaging solutions capable of maintaining biological relevance during long-term experiments, while preserving resolution, stability and usability. Such cases exemplify how instrumentation must adapt to biological reality -not the other way around- if it is to fully serve the end user.

Across all topics, a common theme emerged: beyond technical performance, researchers require integrated, reliable and user-friendly solutions that fit within complex research infrastructure ecosystems. By confronting field practices with industrial perspectives, the visit fostered a shared understanding of operational constraints, technological opportunities and long-term expectations.

This EVOLVE exchange reinforced the role of Euro-BioImaging and its national nodes, including France-BioImaging and the BIC, as catalysts for structured dialogue between research infrastructures and industry. By anchoring innovation in real user environments and evolving scientific needs, the initiative contributes to shaping sustainable, co-designed technological developments that ultimately benefit the research community.

Accurately measuring biochemical activity in living cells is a major challenge in bioimaging. FRET microscopy (Fluorescence Resonance Energy Transfer) is widely used for this purpose: it relies on energy transfer between two fluorophores in close proximity, making it possible to monitor molecular interactions or protein conformational changes in real time. While powerful, FRET remains difficult to exploit quantitatively, as results are often highly dependent on instrumental settings and experimental conditions.

To address these limitations, a multidisciplinary team of physicists and biologists from LIPHY, led by Aurélie Dupont, developed QuanTI-FRET, an innovative approach now available as a plug-in for napari.

The originality of the method lies in an auto-calibration strategy performed directly on the experimental images, exploiting the known stoichiometry of intramolecular FRET biosensors. This approach eliminates the need for additional calibration constructs and significantly simplifies the experimental workflow. Validated on live-cell FRET experiments, it enables the extraction of robust and comparable quantitative FRET values.

Released as open-source software and integrated into an open Python-based analysis environment, QuanTI-FRET contributes to making quantitative FRET imaging more accessible and reproducible for the bioimaging community.

Here’s the napari plug-in: https://napari-hub.org/plugins/quanti-fret.html

Interested to learn more? Read their scientific article here.

Tomographic Diffraction Microscopy (TDM) enables quantitative, label-free three-dimensional imaging of transparent samples, but its performance is limited when applied to thick or structurally complex specimens. Depth-dependent signal degradation and asymmetric frequency sampling can compromise both image quality and quantitative accuracy. To address these challenges, a research team from IRIMAS (France-BioImaging Alsace node) has developed a dual-view TDM approach. By combining two opposite and complementary views of the same sample, this method improves the robustness, reliability and applicability of 3D TDM reconstructions.

Limitations of conventional transmission TDM

TDM relies on the diffraction of light as it propagates through materials with different optical properties. By recording the phase and amplitude of the diffracted light under multiple illumination angles, TDM reconstructs a 3D map of the sample’s refractive index and absorption without the need for fluorescent labelling.

However, in its conventional transmission configuration, TDM suffers from intrinsic limitations. As imaging depth increases, signal quality progressively degrades due to absorption, defocusing and multiple scattering. In parallel, incomplete and asymmetric sampling of spatial frequencies can lead to reconstruction artefacts, such as axial distortions or ambiguities between refractive index and absorption. These effects reduce the reliability of 3D reconstructions, particularly for thick, dense or structurally complex samples.

Dual-view TDM: principle and implementation

To overcome these limitations, the proposed dual-view TDM approach is based on the simultaneous acquisition of two tomographic datasets from opposite directions. Each view provides a full 3D reconstruction of the sample, but with different depth-dependent signal attenuation and complementary spatial frequency coverage.

In this configuration, structures that appear deep and poorly resolved in one view are closer to the surface and better resolved in the opposite view. The two reconstructed volumes are then spatially registered and combined using a dedicated fusion strategy that selects, for each axial plane, the view exhibiting the richest spatial frequency content. This process effectively compensates for depth-related signal loss and mitigates asymmetries in the Optical Transfer Function, resulting in improved axial resolution, reduced reconstruction artefacts and more homogeneous image quality throughout the volume. Both refractive index and absorption maps benefit from this enhanced robustness, leading to more faithful and reliable 3D reconstructions.

Applications in label-free imaging of complex samples

Dual-view TDM is particularly well suited for the label-free imaging of structurally complex samples, where conventional TDM may fail to provide reliable results. Typical applications include the study of samples such as diatoms and pollen grains, whose intricate surface features and internal compartments require homogeneous image quality across the entire sample. The method could also be relevant for small 3D cellular assemblies or spheroids, where depth-dependent signal degradation limits quantitative analysis.

By improving the robustness of refractive index and absorption reconstructions, dual-view TDM enables more accurate characterization of dense or absorbing regions, extending the applicability of TDM to a broader range of biological and biophysical studies without additional labelling or complex sample manipulation.

While dual-view Tomographic Diffraction Microscopy significantly improves the robustness of 3D TDM reconstructions, it does not fully eliminate the intrinsic limitations of transmission-only TDM, such as multiple scattering or anisotropic resolution in very complex samples. This approach nevertheless represents an important contribution in extending the applicability of label-free 3D imaging. This dual-view approach also paves the path towards 4Pi tomography, which aims at delivering isotropic-resolution imaging. Note that another French team at Institut Fresnel-Marseille works on a similar approach, called mirror-assisted tomography.

Readers interested in the technical details and experimental validation can consult the scientific article here.

Carlos Alberto Chacón Ávila, Nicolas Verrier, Matthieu Debailleul, Bruno Colicchio, and Olivier Haeberlé, “Dual-view tomographic diffraction microscopy” Opt. Express 33, 51444-51458 (2025)

Nous avons rencontré Jean-Luc et Brice, qui nous ont fait le plaisir de répondre à nos questions pour mieux comprendre les enjeux et bénéfices de cet échange.

English-speaking readers, the interview can be found in English at the end of the article.

Brice, pouvez-vous brièvement vous présenter ?

[Brice] Je suis Dr Libert Brice TONFACK, Maître de Conférences en Biotechnologies Végétales et Environnement à l’Université de Yaoundé I depuis 2011. Mon parcours s’est construit entre le Cameroun, la France et l’Afrique du Sud, avec un doctorat en biotechnologies végétales et une expérience postdoctorale à l’Université de Pretoria. Mes recherches portent sur la valorisation des plantes tropicales sous-exploitées, l’agriculture durable en conditions de stress et la génomique fonctionnelle, avec pour objectif de relier recherche fondamentale et applications concrètes au service du développement durable en Afrique.

Sur quel projet de recherche travaillez-vous actuellement ?

[Brice] Je travaille actuellement sur un projet consacré à la valorisation d’espèces tropicales sous-exploitées du genre Aframomum, en collaboration avec le CIRAD à Montpellier. À l’aide d’outils de bioimagerie et de microscopie, nous étudions la diversité et la structure des graines. L’enjeu est à la fois scientifique et sociétal : mieux comprendre ces espèces encore peu étudiées, révéler leur potentiel médicinal, alimentaire ou cosmétique, et contribuer à leur conservation ainsi qu’au développement des communautés qui en dépendent.

Brice, comment avez-vous vécu le programme Imaging 4 All – Access Track ?

[Brice] Mon expérience avec ce programme a été très enrichissante. Ce séjour a permis de poser les bases d’une collaboration scientifique ambitieuse et durable entre mon laboratoire et la plateforme MRI-PHiV du CIRAD. L’accueil, l’organisation et l’accompagnement scientifique ont été exemplaires, et les infrastructures de pointe ont permis de générer des données de très grande qualité. Le soutien financier du programme a été déterminant pour la réussite du projet et a eu un impact fort sur mes travaux et mes collaborations internationales.

Pourquoi avoir choisi une plateforme France-BioImaging ?

[Brice] J’ai choisi une plateforme France-BioImaging car l’imagerie végétale reste encore peu représentée, et la MRI-PHiV de Montpellier est l’une des rares infrastructures de haut niveau dédiées à la recherche sur les plantes. J’ai été mis en contact avec Jean-Luc Verdeil par Jean Salamero, puis une première visite de la plateforme en 2024 a permis d’initier les échanges scientifiques et de faire émerger un projet commun, ensuite construit collectivement à distance.

En quoi ce séjour a-t-il fait avancer votre projet ?

[Brice] Ce séjour a permis d’obtenir des données inédites que je n’aurais pas pu acquérir dans mon laboratoire. Nous avons réalisé une caractérisation complète des graines d’Aframomum par imagerie non invasive et analyses histologiques et histochimiques avancées. Ces approches ont généré des jeux de données riches et prometteurs, constituant une avancée méthodologique majeure et posant les bases de travaux collaboratifs approfondis.

Jean-Luc, comment la plateforme a-t-elle bénéficié de cette collaboration ?

[Jean-Luc] Cette collaboration a été très stimulante pour l’ensemble de l’équipe de la MRI-PHiV. Elle nous a permis de travailler sur un matériel biologique original et peu étudié, présentant une grande richesse morphologique et biochimique. Le projet nous a amenés à combiner plusieurs modalités d’imagerie dans une approche intégrative, renforçant notre expertise méthodologique, notamment sur des échantillons complexes riches en métabolites secondaires. Les échanges avec Brice ont été particulièrement riches et son regard de biologiste tropical a donné une nouvelle dimension aux images produites.

En quoi cette collaboration a-t-elle enrichi vos approches scientifiques ?

[Brice] Cette collaboration a renforcé ma conviction que l’imagerie est un outil central pour comprendre le fonctionnement du végétal: une bonne image valant mille mots! Elle m’a conduit à repenser l’ensemble de la chaîne expérimentale, de la préparation des échantillons à l’analyse des images. L’imagerie, en interaction avec la physiologie, la biochimie, la génomique et l’agronomie, ouvre un véritable changement de paradigme scientifique.

[Jean-Luc] Travailler avec Brice sur des espèces tropicales orphelines a profondément enrichi ma manière d’aborder l’imagerie végétale, en la replaçant au cœur de questions biologiques, écologiques et sociétales concrètes. L’imagerie ne doit pas être perçue comme une discipline isolée, mais comme un langage transversal reliant la physiologie, la biochimie, la génomique, l’agronomie et l’écologie. Cette collaboration nous a amenés à repenser la conception des protocoles et la finalité des données produites, et a également été très riche sur le plan humain, en instaurant une relation de confiance essentielle à des partenariats durables.

Brice, qu’avez-vous retiré de cette expérience sur le plan professionnel ?

[Brice] Au-delà de l’accès aux technologies, cette expérience a fortement renforcé ma visibilité internationale et celle de mon institution. J’ai pu me familiariser avec des outils de microscopie de haut niveau et générer un volume important de données, qui seront analysées en étroite collaboration avec l’équipe de la MRI-PHiV.

Comment Global BioImaging favorise-t-il des collaborations équilibrées ?

[Jean-Luc] Les initiatives portées par Global BioImaging dépassent une simple logique d’accès aux équipements. Elles encouragent la co-construction de projets, la reconnaissance des expertises et des priorités scientifiques des pays du Sud, et contribuent à réduire les inégalités d’accès aux technologies. Elles bénéficient autant aux chercheurs invités qu’aux plateformes hôtes et créent un cadre de confiance propice à des collaborations durables. J’ai par ailleurs énormément apprécié de travailler avec Brice, que je ne connaissais que très peu avant cette collaboration. Cette rencontre a été pour moi une expérience humainement très enrichissante, tant sur le plan personnel que culturel et scientifique, et elle a largement contribué à la qualité, à la confiance et à la profondeur de notre collaboration.

Comment envisagez-vous la suite de cette collaboration ?

[Brice] Oui, clairement. L’analyse des données nécessitera une collaboration étroite sur au moins un an, avec des publications, des communications scientifiques et de nouveaux séjours de recherche. À plus long terme, nous envisageons des échanges d’étudiants, des actions de formation et des projets communs, notamment en biotechnologie forestière et en imagerie appliquée aux écosystèmes marins.

[Jean-Luc] Cette collaboration constitue le point de départ d’un partenariat scientifique structurant et durable. À court terme, l’analyse conjointe des données ouvrira la voie à plusieurs publications. À plus long terme, nous souhaitons développer des échanges de jeunes chercheurs, des formations en imagerie et répondre ensemble à de futurs appels à projets autour de l’imagerie végétale et du phénotypage des plantes tropicales.

France-BioImaging CLEM Working Group will organize its next Workshop from March 10 to 12, 2026 in Rouen (Normandie).

This edition, mainly focused on cryo-CLEM will combine theoretical presentations the 1^st day, practical workshop the 2^nd day and a visit of the Primacen facility the 3^rd day (morning only).

Look at the complete program:

Registration are open until February 18, 2026. All WG-CLEM members are welcome in Rouen, up to a maximum of 12 participants (travel, accommodation, restaurant supported by your home node).

To register, fill in the form: https://forms.gle/dvFTjiDnvVQk4HkWA

Download the file below for practical information.

A model symbiosis reveals a specific nutrient exchange strategy

Many insects rely on intracellular bacterial symbionts to support their growth and development. These bacteria provide essential nutrients that the host cannot synthesize on its own, while depending on the insect for metabolic resources. Although this mutual dependence is well established, the cellular mechanisms underlying nutrient exchange between hosts and symbionts have long remained unclear.

In this study, the authors focus on a model of nutritional symbiosis between the cereal weevil Sitophilus spp. and its intracellular bacterial symbiont Sodalis pierantonius. By investigating this specific host-symbiont system, the researchers reveal how S. pierantonius directly accesses carbohydrates derived from the insect diet. Using advanced imaging approaches, they uncover an unexpected intracellular organization that enables efficient nutrient transfer at the nanoscale in this particular symbiotic context.

Seeing nutrient exchange across scales

To investigate this well-defined symbiotic model, the study relied on a combination of complementary imaging techniques to visualize nutrient exchange from the tissue scale down to the nanoscale.

Transmission electron microscopy (TEM) and electron tomography, performed after high-pressure freezing (HPF), provided high-resolution 3D views of host cells, with excellent preservation of membranes. These experiments, carried out at the Centre Technologique des Microstructures, a platform of the Rhône-Alpes node of France-BioImaging, were essential to resolve fine bacterial membrane structures. In parallel, spinning disk confocal microscopy enabled fluorescence imaging of intact tissues, while scanning transmission X-ray microscopy (STXM) provided in situ chemical information.

Imaging reveals tubenets as key nutrient exchange interfaces

The imaging data first establish the spatial organization of the symbiosis within the insect. Symbiotic bacteria are confined to a specialized organ, the bacteriome, and are intracellularly localized within host bacteriocytes. This organization defines a highly structured cellular environment in which host and symbiont interactions take place.

At the cellular level, the bacteria display an unexpected morphological complexity. Rather than remaining as isolated intracellular units, Sodalis pierantonius forms an extensive network of tubular membrane structures, termed tubenets, within bacteriocytes. These structures extend from the bacterial surface and interconnect neighboring bacterial cells, giving rise to a continuous three-dimensional network embedded in the host cytoplasm.

High-resolution observations further reveal that tubenets originate from the bacterial outer membrane. Their molecular features include characteristic components of bacterial outer membranes, indicating that they result from a controlled remodeling of the bacterial envelop rather than from host-derived compartments. This remodeling generates an expanded membranous architecture while preserving bacterial membrane identity.

The spatial arrangement of tubenets places them in close proximity to host intracellular vesicles associated with nutrient trafficking from the digestive epithelium. Based on the convergence of spatial, structural and molecular observations, the authors propose that tubenets function asspecialized interfaces at the host-symbiont boundary.

According to this proposed model, the expansion of membrane surface provided by tubenets would facilitate the access of symbiotic bacteria to host-derived nutrients. These nutrients would support bacterial metabolism and contribute to the synthesis of essential compounds, such as amino acids, which are required for the normal growth and development of the insect host during key developmental stages.

Imaging to understand the diversity of host-symbiont interactions

Beyond this specific model system, the work highlights how advanced imaging approaches are essential to uncover the structural basis of biological functions that remain inaccessible through genetic or biochemical analyses alone. By integrating information across spatial scales, from tissues to membranes,imaging makes it possible to connect cellular architecture with metabolic and developmental processes.

Read the scientific article here!