Membrane & Immunity Team (Franck Fieschi)

Team leader: Franck FIESCHI (Professor, UGA)

Membres actuels

Franck Fieschi (Pr - UGA, IUF)
Marie José Stasia (MCUPH - UGA)
Cédric Laguri (CR - CNRS)
Michel Thépaut (IR - CNRS)
Isabelle Petit-Hartlein (AI - CNRS)
Perinne Rochas (PhD - UGA)
Massilia Abbas (PhD - UGA)
Maria Val-Pevida (PhD - UGA)

Expertise

Membranes proteins biochemistry ; Biophysics of interactions (SPR, ITC, BLI ); X-Ray Crystallographie ; Nuclear Magnetic Resonance ; CryoElectron Microscopy.

Key Words

Redox Biochemistry, Glycobiology, Membrane Protein, Immunity, C-type Lectin Receptors, NADPH Oxidase complexes.

Introduction

The functioning of the immune system involves many stages of cell-cell interaction, host-pathogen, and cell activation for the initiation of the immune response, which require a diversified arsenal of membrane proteins that differ from one cell type to another. Because of their roles in human health, these proteins are of major interest for both fundamental and for applied medical research. Despite the methodological pitfalls of working on eukaryotic membrane proteins, we are committed investigating two major protein families: C-type lectin receptors (CLRs) and NADPH oxidase from the NOX Family. CLRs recognize saccharide patterns as non-self or self-altered and modulate the associated immune response. NOX enzymes generate reactive oxygen species used as a cytotoxic agent and also for signaling in many tissues; misregulation leads to oxidative stress and diseases.

NADPH oxidases from the NOX Family.

  • Eukaryotic NOX Enzymes.
    – Contact: Marie José Stasia, Franck FIESCHI.
    – Involved staff: Michel Thépaut, Isabelle Hartlein, Perrine Rochas & Maria Val Pevida.

NOXs enzymes are membrane redox enzymes involved in the production of reactive oxygen species (ROS). NOX enzymes and their reactive products are involved in many key physiological function (cardiovascular tone regulation, hormone synthesis, balance, fertility…) making them attractive target for many pharmaceutical applications. Notably, NOX has been initially identified as a key factor for innate immunity as illustrated in Chronic Granulomatous Disease (CGD). CGD is an inherited immunodeficiency in which patients lack a functional NOX2. Marie José Stasia in the group leads a CGD diagnostic center at CHU Grenoble Alps. Using mutations identified in patients, we are reconstituting them recombinantly and characterising their functional and structural impact using integrated approaches ranging from biophysics to immunology.

  • Prokaryotic NOX Homologs.

– Contact: Franck FIESCHI.
– Involved staff: Michel Thépaut, Isabelle Hartlein.

To help elucidate the molecular mechanisms and structures of NOXs, we have developed studies on prokaryotic NOX homologs. We are focusing on production and characterization of the Streptococcus pneumonia NOX (SpNox). Part of this work is made in partnership with Pr. Susan Smith from KSU, Georgia-USA.
We are also studying another bacterial homologue, MsrQ, which corresponds only to the transmembrane part of eukaryotic NOX.


Key results for 2019-2024:
Over the past five years, we have characterized the structure and redox mechanisms of a bacterial NOX-analogue, SpNOX, firstly using small-angle neutron scattering (SANS) and then X-ray crystallography. This structural information was extensively supplemented by detailed enzymatic and mechanistic characterisation. We have also developed new expression systems for the recombinant production of the NOX enzyme from human neutrophils. Additionally, we created new cellular tools, phagocytic cell lines with knocked-down NOX subunits, enabling us to initiate the development of therapeutic approaches for inherited immune defects (Chronic Granulomatous Disease-CGD) caused by genetic NOX inactivation.

Collaborations :
– Félix Weis, IBS, Grenoble, France.
– Susan Smith, Kennesaw State University, Georgia, USA.
– Ulla Knaus, University College Dublin, Ireland.

C-type lectin receptors (CLRs).

CLRs are pathogen recognition receptors essential to immune system for recognition and signaling. CLRs recognize specific carbohydrate-based motifs and play a critical role in the processes leading to antigen presentation by dendritic cells. Different CLRs recognize different patterns, inducing either activation or repression of the immune response. However, pathogens like HIV, SARS-CoV-2 and M. tuberculosis can hijack CLRs and evade the immune system. CLRs can be targeted, depending on the context, for vaccination strategies, immune activation, anti-infective agents, etc., making them attractive for drug discovery.

Développements d’outils, de méthodes et de ligands spécifiques
– Contact : Franck Fieschi.
– Involved staff: Michel Thépaut, Franck Fieschi.

  • Development of recombinant production of human CLRs: actually 10 different human lectins.
  • Development of new tools: artificial multivalent lectins, oriented interaction surfaces, Lectin-array
  • Ligand optimization and screening approaches: glycan arrays, glycomimetic arrays.
  • Structural characterization of receptor/ligand complexes.

Host-pathogens Interactions
– Contact : Cédric Laguri, Franck FIESCHI.
– Involved staff: Massilia Abbas, Michel Thépaut, Cédric Laguri, Franck Fieschi.

  • Viruses recognition by CLRs
  • Gram- bacteria recognition by CLRs (with lipopolysaccharides) : Development of bacterial outer membrane mimics.
  • Gram- bacteria recognition by CLRs

Immunity, Cancer and CLRs
– Contact : Franck FIESCHI.
– Involved staff: Michel Thépaut, Franck Fieschi.

  • Cancer cells recognition by CLRs
  • Cancer, CLRs and signaling of the immune system

Key results for 2019-2024:

Our previous research concentrated on the interaction between CLRs and viruses (HIV, Dengue) and thus when the COVID-19 pandemic began, we quickly adapted to address the emerging crisis. We obtained tools to express the Spike protein already in March 2020. We initiated, with the support of our Institut Director, an IBS COVID-Task force of volunteers (15 persons) to initiate the production of recombinant Spike protein while the world was going in its first lockdown. This effortmade it possible to provide the other IBS groups with the Spike production tools and protocols for their return in May 2020 and to support further studies, including for us, the Spike interactions with cell membranes (coll. ILL). Mainly, we demonstrated that CLRs contribute to an alternative mode of COVID-19 dissemination, through trans-infection, mediated by the recognition of the Spike protein’s glycans by specific CLRs (DC-SIGN and L-SIGN). During this period, we also developed tools, including SPR surface engineering, to characterize the multivalent interactions typical of these glycan-CLR complexes. In collaboration with the University of Milan, we have created, characterised and patented selective glycomimetic antagonists targeting CLRs, particularly for applications in the context of COVID-19. The modes of interaction of these ligands were characterised by X-ray crystallography of the Lectin/Glycomimetic complexes. In the latter part of the quinquennial, we began exploring the role of CLRs in recognizing gram-negative bacteria through their lipopolysaccharides (LPS). This led to a new collaboration with a group in Naples specializing in LPS production, and the development of dedicated tools (models of Gram- outer membranes) for studying LPS/CLRS interactions (Cedric Laguri joined the team in 2023). Over the five-year period we have also continued, mainly through local collaborations (JL Coll and C. Aspord), to characterise the CLRs/Cancer link in the anti-tumour immune response and also to produce tools based on specific lectins for targeting cancer cells with a specific altered glycan profile.

Collaborations:
– Javier Rojo, Instituto de Investigaciones Quimicas, Sevilla, Spain.
– Anna Bernardi, University of Milano, Italy.
– Niels Reichardt, CIC biomaGUNE, San Sebastian, Spain.
– Peter H. Seeberger, Bernd Lepenies and Christoph Rademacher, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
– Jean-Pierre Simorre and Cédric Laguri, IBS, Grenoble.
– Antonio Molinaro, University of Naples Federico II, Italy.
– Franck Halary, University of Nantes.
– Yoann Rombouts, Institute of Pharmacology and Structural Biology, Toulouse.
– Jean-Luc Coll, Institute for Advanced Biosciences, Grenoble.
– Olivier Renaudet, University of Grenoble.
– Pedro Manuel Nieto Mesa and Jesus Angulo, Institute for Chemical Research (IIQ), Sevilla, Spain.
– Anne Imberty, CERMAV, Grenoble.

Patent

Pollastri S, Bernardi A, Delaunay C, Thepaut M, Fieschi F.
Glycomimetic binders for L-SIGN.
WO/2023/209586.

Alumni

Clara Delaunay (PhD 2020-2023, Doctoral School UGA)
Eugénie Laigre (Post Doc, 2020-2022, ANR Lect Array)
Poushalee Dutta (M2, 2022)
Quentin Durieux (M2, 2020)
Yasmina Grimoire (CDD IE, 2019-2021, ANR Lect Array)
François Bulteau (PhD 2017-2020, GlycoALps - Idex UGA)
Annelise Vermot (PhD 2016-2020, Program Emergence - UGA)
Silvia Achilli (PhD 2015- 2018, ITN Marie curie "Immunoshape" - Horizon 2020)
Vanessa Porkolab (PhD 2013-2016, Region Rhône-Alpes)
Pascal Gabard (CDD, 2013-2015, Coll. Industriel)
Christine Hajjar (PhD 2011-2014, Doctoral School UGA)
Antoine Picchiocci (Post doc 2009-2013)
Ieva Sutkeviciute (PhD 2009-2012; ITN Marie curie "Carmusys" - 7ème PCRD)
Lina Siauciunate (PhD 2009-2012, ITN SBMP - 7ème PCRD)
Eric Chabrol (PhD 2008 -2012, EDoctoral School UGA)
Julien Marcoux (PhD 2006-2010, CFR CEA)
Georges Tabarani (PhD 2004-2008, CFR CEA)
Sylvie Chenavas PhD 2001-2005, UGA)
Corinne Houlès (Post Doc 2001-2003, Sidaction)
Corinne Vivès (Post Doc 2000-2002, ANRS)
Claire Massenet (PhD 1998-2002, UGA)