Department: PIV

Biological membranes: structure, function and interactions

Leader: K. Sengupta


In-vitro reconstitution of focal-adhesions

Principal investigators: K. SENGUPTA & E. HELFER

PhD Student: M. Souissi (2019-2022)

Collaborations: C. Le Clainche (I2BC, Gif sur Yvette France)

Funding: ANR RECAMECA (2019-2022)

Cell biophysics and proteomics have revealed key links between force, integrin and the mechanical properties of the extra cellular matrix (ECM). However, in-cellulo, the existence of multiple isoforms of actin binding proteins, their embedding in a complex signaling network, and their associated with a complex membrane environment precludes extraction of even elementary molecular mechanisms. To reveal these force-dependent molecular mechanisms, we need to isolate actomyosin-integrin-ECM circuits. The global objective of our project is to decipher the molecular links between actomyosin force, integrin regulation and ECM properties through in vitro reconstitution of focal adhesions.

As a first step towards this goal, we have successfully integrated transmembrane integrins into giant unilamellar vesicles (GUVs) and demonstrated their functionality. We are also developing an alternative to fully in vitro reconstitution, namely cell derived giant plasma membrane vesicles (GPMVs). This alternative does not require elaborate biochemistry needed for integrin extraction and purification, yet offers many of the advantages of in vitro reconstitution.

Physics of membrane adhesion

Principal investigators: K. Sengupta; F. Thibaudau

PhD Student:  Ahmed Abdurahman (2019-)

Postdoc: Arnauld Hemmerlé (2016-2018), M. Arif Kamal (2014-2016)

Collaboration: Ana smith (Univ. Erlangen, Germany)

Funding: ANR-DGF MicroCJ (2019-2022), AMIDEX Affinity (2015-2019)

We have recently shown that from the spectrum of fluctuations recorded with the experimental techniques previously developed in the team, it is possible to measure the membrane interaction potential. We have also shown that transverse fluctuations can modulate the nucleation and growth of lateral adhesion domains. In addition, we have used soluble DNA oligomers to mimic binding between intracellular organelles and have shown that the physics of this system is very different from that of cell adhesion with ligands in the membrane. Currently, we are exploring the nucleation and growth of adhesion domains in the context of weak bonds where entropy can dominate the enthalpy generated by bond formation.

Shape and dynamics of vesicles in flow: theory and simulations

Principal investigator: M. Leonetti

Collaboration : P. G. Chen, M. Jaeger (M2P2, Marseille)

A vesicle is a droplet bounded by a lipid bilayer embedded in another liquid. This system knows a long standing interest due to its ability to mimic some properties of red blood cells. But it is also a fascinating system at a theoretical point of view, thanks to its original interfacial properties: resistance to bending and local surface incompressibility.  It is one of the ways to understand how soft matter flows. We study the shape and the spatiotemporal dynamics of vesicles in flow or in electric field by a methodology associating theory and numerical simulations.  We have developed our own code based on Finite Element Method and Boundary Element Method. The instabilities are characterized in the framework of nonlinear physics and soft matter. The results can highlight some behaviors of red blood cells in microcirculation.


Principal investigator: M. Leonetti

A - Dynamics, shape, wrinkling and rupture of an elastic capsule

PhD Student: P. Regazzi

Funding: CNES

Encapsulation is a simple way of protecting, transporting and delivering internalized principles, but also of structuring space. This concerns very diverse fields such as food, cosmetics, new materials for construction or medicine. The capsules studied are droplets bounded by a thin polymer film (shell) and immersed in a liquid. The structural and mechanical properties of such objects are still poorly known: behaviour laws, elastic and viscous moduli, rupture, dynamics, etc. Indeed, there are few experimental results. The behavior of this closed elastic system is governed by the coupling at the interface between the viscous stress jump and the elastic response of the shell (also called skin or membrane depending on the domain).

We are interested in the rupture of capsules as a function of the nature of its membrane, the winkling/folding instabilities and the spatiotemporal dynamics of the shape by a multiscale analysis.

B – Interactions between capsules, collective behaviors

The strong deformation of capsules in flow induces more complex hydrodynamic interactions than between rigid particles. To this, it is necessary to add colloidal interactions as well as friction, key ingredients for the understanding of the rheology of rigid particle suspensions. We propose to study the implication of all these contributions to the case of binary interactions and more broadly in suspension.



Physics of (T) cell adhesion

Principal investigators: K. Sengupta

PhD Student:  Remy Torro (2019- ), Aya Nassereddine (2018-2021), Celine Dinet (2016-2019), Emmanuelle Benard (2015-2018), Pierre Dillard (2011-2016)

Postdocs: Zakaria Marmri (2022-), Fuwei Pi (2011-2013)

Collaboration : Laurent Limozin (LAI, Marseille France).

Funding: SATT (2019- ), CENTURI (2019 - ), ERC (SYNINTER 2013-2017), ATER AMU (2018), AMU ED 352 PhD grant (2014-2017), Region PACA (MadNano 2011-2013), PhD grant AMU (2011-2014)

We have developed innovative surface nano-patterning techniques to manipulate living cells to reveal aspects of cell adhesion. These surfaces feature regularly spaced islands of cell-activating proteins of nano- or submicron size with which cells can be induced to interact. They are imaged by advanced surface microscopy techniques that may not be applicable to traditional nano-patterning with metal nanoparticles. Using these surfaces, we have shown that the cell-scale behaviour of T cells is governed by the average protein density and not by their nanoscale organisation, which however has a strong impact on the local organisation of the membrane. Using a new AI analysis technique, we showed that actin organisation remains unaffected even locally.


University Lecturer

Postdoctoral fellow



Transit Time Theory for a Droplet Passing through a Slit in Pressure-Driven Low Reynolds Number Flows

Spencer W Borbas, Kevin Shen, Catherine Ji, Annie Viallat, Emmanuèle Helfer, Zhangli Peng

Micromachines 14:2040 (2023)10.3390/mi14112040

Classification of red cell dynamics with convolutional and recurrent neural networks: a sickle cell disease case study

Maxime Darrin, Ashwin Samudre, Maxime Sahun, Scott Atwell, Catherine Badens, Anne Charrier, Emmanuèle Helfer, Annie Viallat, Vincent Cohen-Addad, Sophie Giffard-Roisin

Scientific Reports 13:745 (2023)10.1038/s41598-023-27718-w

Enhanced cell viscosity: a new phenotype associated with lamin A/C alterations

Cécile Jebane, Alice-Anaïs Varlet, Marc Karnat, Lucero Hernandez- Cedillo, Amélie Lecchi, Frédéric Bedu, Camille Desgrouas, Corinne Vigouroux, Marie-Christine Vantyghem, Annie Viallat, Jean-François Rupprecht, Emmanuèle Helfer, Catherine Badens

iScience 26:107714 (2023)10.1016/j.isci.2023.107714

Probing mechanical interaction of immune receptors and cytoskeleton by membrane nanotube extraction

Fabio Manca, Gautier Eich, Omar N’dao, Lucie Normand, Kheya Sengupta, Laurent Limozin, Pierre-Henri Puech

Scientific Reports 13:15652 (2023)10.1101/2022.09.15.508080

Physical mechanisms of red blood cell splenic filtration

Alexis Moreau, François Yaya, Huije Lu, Anagha Surendranath, Anne Charrier, Benoit Dehapiot, Emmanuèle Helfer, Annie Viallat, Zhangli Peng

Proceedings of the National Academy of Sciences of the United States of America (2023)10.1101/2023.01.10.523245

Talin and kindlin cooperate to control the density of integrin clusters

Julien Pernier, Marcelina Cardoso Dos Santos, Mariem Souissi, Adrien Joly, Hemalatha Narassimprakash, Olivier Rossier, Grégory Giannone, Emmanuèle Helfer, Kheya Sengupta, Christophe Le Clainche

Journal of Cell Science 136:jcs260746 (2023)10.1242/jcs.260746

Analytical theory for a droplet squeezing through a circular pore in creeping flows under constant pressures

Zhengxin Tang, François Yaya, Ethan Sun, Lubna Shah, Jie Xu, Annie Viallat, Emmanuèle Helfer, Zhangli Peng

Physics of Fluids 35:082016 (2023)10.1063/5.0156349


Dynamics of Individual Red Blood Cells Under Shear Flow: A Way to Discriminate Deformability Alterations

Scott Atwell, Catherine Badens, Anne Charrier, Emmanuèle Helfer, Annie Viallat

Frontiers in Physiology 12 (2022)10.3389/fphys.2021.775584

First-Principle Coarse-Graining Framework for Scale-Free Bell-Like Association and Dissociation Rates in Thermal and Active Systems

Josip Augustin Janeš, Cornelia Monzel, Daniel Schmidt, Rudolf Merkel, Udo Seifert, Kheya Sengupta, Ana-Sunčana Smith

Physical Review X 12:031030 (2022)10.1103/PhysRevX.12.031030

Physics of Organelle Membrane Bridging via Cytosolic Tethers is Distinct From Cell Adhesion

Mohammad Arif Kamal, Josip Augustin Janeš, Long Li, Franck Thibaudau, Ana-Sunčana Smith, Kheya Sengupta

Frontiers in Physics 9:1-12 (2022)10.3389/fphy.2021.750539

May the force be with your (immune) cells: an introduction to traction force microscopy in Immunology

Farah Mustapha, Kheya Sengupta, Pierre-Henri Puech

Frontiers in Physics 13:898558 (2022)10.3389/fimmu.2022.898558

A Rare Mutation in LMNB2 Associated with Lipodystrophy Drives Premature Cell Senescence

Alice-Anaïs Varlet, Camille Desgrouas, Cécile Jebane, Nathalie Bonello-Palot, Patrice Bourgeois, Nicolas Levy, Emmanuèle Helfer, Noémie Dubois, René Valero, Catherine Badens, Sophie Beliard

Cells 11:50 (2022)10.3390/cells11010050


Biomechanics as driver of aggregation of tethers in adherent membranes

Long Li, Mohammad Arif Kamal, Bernd Henning Stumpf, Franck Thibaudau, Kheya Sengupta, Ana-Sunčana Smith

Soft Matter 17:10101-10107 (2021)10.1039/d1sm00921d

Ligand Nanocluster Array Enables Artificial-Intelligence-Based Detection of Hidden Features in T-Cell Architecture

Aya Nassereddine, Ahmed Abdelrahman, Emmanuelle Benard, F. Bedu, Igor Ozerov, Laurent Limozin, Kheya Sengupta

Nano Letters 21:5606-5613 (2021)10.1021/acs.nanolett.1c01073

Thermoplasmonics of metal layers and nanoholes

Benoit Rogez, Zakaria Marmri, Franck Thibaudau, Guillaume Baffou

APL Photonics 6:101101 (2021)10.1063/5.0057185

On the control of dispersion interactions between biological membranes and protein coated biointerfaces

Kheya Sengupta, Robert Blackwell, Arnaud Hemmerle, Andreas Baer, Matthias Späth, Wolfgang Peukert, Drew Parsons, Ana-Sunčana Smith

Journal of Colloid and Interface Science 598:464-473 (2021)10.1016/j.jcis.2021.02.078

Integrin-Functionalised Giant Unilamellar Vesicles via Gel-Assisted Formation: Good Practices and Pitfalls

Mariem Souissi, Julien Pernier, Olivier Rossier, Gregory Giannone, Christophe Le Clainche, Emmanuèle Helfer, Kheya Sengupta

International Journal of Molecular Sciences 22:6335 (2021)10.3390/ijms22126335


Mechanical adaptation of monocytes in model lung capillary networks

Jules Dupire, Pierre-Henri P Puech, Emmanuèle Helfer, Annie Viallat

Proceedings of the National Academy of Sciences of the United States of America 117:14798 (2020)

Molecular and Mechanobiological Pathways Related to the Physiopathology of FPLD2

Alice-Anaïs Varlet, Emmanuèle Helfer, Catherine Badens

Cells 9:1947 (2020)10.3390/cells9091947


Self-organization of red blood cell suspensions under confined 2D flows

Cécile Iss, Dorian Midou, Alexis Moreau, Delphine Held, Anne Charrier, Simon Mendez, Annie Viallat, Emmanuèle Helfer

Soft Matter (2019)10.1039/C8SM02571A

Biphasic mechanosensitivity of T cell receptor-mediated spreading of lymphocytes

Astrid Wahl, Céline Dinet, Pierre Dillard, Aya Nassereddine, Pierre-Henri Puech, Laurent Limozin, Kheya Sengupta

Proceedings of the National Academy of Sciences of the United States of America 116:5908-5913 (2019)10.1073/pnas.1811516116


T Cells on Engineered Substrates: The Impact of TCR Clustering Is Enhanced by LFA-1 Engagement

Emmanuelle Benard, Jacques Nunès, Laurent Limozin, Kheya Sengupta

Frontiers in Immunology 9 (2018)10.3389/fimmu.2018.02085

Lamellipod Reconstruction by Three-Dimensional Reflection Interference Contrast Nanoscopy (3D-RICN)

Marie-Julie Dejardin, Arnaud Hemmerle, Anais Sadoun, Yannick Y. Hamon, Puech Pierre-Henri, Kheya Sengupta, Laurent Limozin

Nano Letters 18:6544-6550 (2018)10.1021/acs.nanolett.8b03134

When giant vesicles mimic red blood cell's dynamics: swinging of two-phase vesicles in shear flow

Simon Tusch, Etienne Loiseau, Al-Hair Al-Halifa, Kamel Khelloufi, Emmanuèle Helfer, Annie Viallat

Physical Review Fluids 3 (2018)10.1103/PhysRevFluids.3.123605


Printing functional protein nano-dots on soft elastomers: from transfer mechanism to cell mechanosensing

Ranime Alameddine, Astrid Wahl, Fuwei Pi, Kaoutar Bouzalmate, Laurent Limozin, Anne Charrier, Kheya Sengupta

Nano Letters 17:4284-4290 (2017)10.1021/acs.nanolett.7b01254

Ligand Nano-cluster Arrays in a Supported Lipid Bilayer

Emmanuelle Benard, Fuwei Pi, Igor Ozerov, Anne Charrier, Kheya Sengupta

Journal of visualized experiments : JoVE 122:e55060 (2017)10.3791/55060

Membrane fluctuations mediate lateral interaction between cadherin bonds

Susanne Fenz, Timo Bihr, Daniel Schmidt, Rudolf Merkel, Udo Seifert, Kheya Sengupta, Ana-Sunčana Smith

Nature Physics 13:906-913 (2017)10.1038/NPHYS4138

High Aspect Ratio Sub-Micrometer Channels Using Wet Etching: Application to the Dynamics of Red Blood Cell Transiting through Biomimetic Splenic Slits

Priya Gambhire, Scott Atwell, Cécile Iss, Frédéric Bedu, Igor Ozerov, Catherine Badens, Emmanuèle Helfer, Annie Viallat, Anne Charrier

Small 13:1700967 (2017)10.1002/smll.201700967