Investigating Regulatory T cells Stability and the Impact of Targeted Therapies in a mice model of multiple sclerosis

Responsable de l’encadrement : Pr Natacha Bessis

Tél 01 48 38 76 98           E-mail:  natacha.bessis@univ-paris13.fr

Faculté de médecine UFR SMBH

Résumé du Projet de Stage

Multiple sclerosis (MS) is a chronic neurological disorder that affects the central nervous system (CNS), which includes the brain and spinal cord. It is considered an autoimmune disease, since the CNS experiences demyelinating lesions and neurodegeneration due to an autoimmune response.

Regulatory T lymphocytes (Treg) play a critical role in preventing autoimmunity. Patients with MS, whose Treg have decreased suppressive activities, experience heightened CNS inflammation and autoreactivity. Recent progress in the field of Treg biology has introduced the concept of Treg stability and its association with chronic inflammation related to autoimmunity. In MS and its animal models, the decline in Treg suppressive activity may be linked to alterations in their stability. The majority of studies indicating a deficiency in Treg cells in MS and its animal models have been carried out in the systemic compartment, rather than at the site of inflammation (CNS).

The primary goal of our team is to gain a deeper understanding of the involvement of regulatory T lymphocytes (Treg) at the site of chronic inflammation, namely the CNS. We work in an experimental model of MS known as experimental autoimmune encephalomyelitis (EAE), in mice. Several targeted therapies are currently used in patients with MS and have also been investigated in the context of EAE to modulate the immune response and reduce disease severity. The global aim of the master 2 internship will be to evaluate the effect of EAE targeted therapy treatments on the stability of Treg in mice with EAE.

The upcoming steps will be as follows:

  1. Inducing EAE in mice and assessing the therapeutic effects of various targeted therapies on the clinical and histological manifestations of the disease. This evaluation will enable us to identify the most effective treatment to be used in subsequent steps.
  2. Examining the suppressive activity of Treg in mice treated with or without the chosen targeted therapy, and comparing the outcomes in both the peripheral compartments (spleen and lymph nodes) and the CNS (brain and spinal cord).
  3. Identifying the genes, particularly those involved in Treg stability, that display differential regulation between the CNS and the periphery in mice with EAE, whether treated or untreated with the selected targeted therapy. The results obtained will help determine whether Treg in the local inflammatory site (CNS) exhibit up- or down-regulation of distinct pathways related to suppressive functions and stability, and whether these pathways are modified under treatment.

 In a technical point aspect, the upcoming steps will include:

  1. Animal experimentation: EAE induction in mice by immunization with MOG in complete Freund adjuvant, administration of treatment, and evaluation of disease (clinical observation and histological analysis of the brain).
  2. Treg FACS-sorting by cell sorter, cell culture, and ELISA: FoxP3-GFP mice will be used to sort Treg based on GFP expression. Purified Treg and conventional T cells (Tconv) will be co-cultured to assess the suppressive effects of Treg on Tconv proliferation and cytokine secretion.
  3. RNAseq: EAE will be induced in FoxP3-GFP mice, with or without targeted therapy. Subsequently, Treg cells will be FACS-sorted from the CNS, LN, and spleen. The transcriptome of Treg from the CNS will be compared to that of the spleen and LN in mice receiving or not treatment, using RNA sequencing (RNAseq) experiments.

 Dernières Publications en lien avec le projet :

-Santinon F, Batignes M, Mebrek ML, Biton J, Clavel G, Hervé R, Lemeiter D, Breckler M, Busato F, Tost J, Ziol M, Boissier MC, Decker P, Semerano L, Bessis N. Involvement of Tumor Necrosis Factor Receptor Type II in FoxP3 Stability and as a Marker of Treg Cells Specifically Expanded by Anti-Tumor Necrosis Factor Treatments in Rheumatoid Arthritis. Arthritis Rheumatol. 2020 Apr;72(4):576-587. doi: 10.1002/art.41134. Epub 2020 Feb 20

Ce projet s’inscrit dans la perspective d’une thèse

 Ecole Doctorale de rattachement : ED Galilée (ED146)

                                       

Equipe d’Accueil :

Intitulé de l’Unité : INSERM UMR 1125

Nom du Responsable de l’Unité : Pr MC Boissier

Nom du Responsable de l’Équipe : Unité monoéquipe

Adresse :  Faculté de médecine UFR SMBH, Université Sorbonne Paris Nord, 1 rue Chablis 93017 Bobigny

Responsable de l’encadrement : Pr Natacha Bessis

Tél 01 48 38 76 98           E-mail:  natacha.bessis@univ-paris13.fr