H2020Individual fellowship2017–2019

GD TCR LIGAND · Identification of the ligand of a human public anti-HCMV/cancer γδ T cell receptor

Horizon 2020 — Marie Skłodowska-Curie Actions

Duration
2017-03-01 → 2019-02-28
EU contribution
€160,800
Participants
1
Scheme
MSCA-IF

Lines connect the coordinator with its partners.

Results in brief

Identification of the ligand of a human public anti-HCMV/cancer γδ T cell receptor

γδ T cells, an important compartment of adaptive immune responses against infections and malignant transformation, have been proposed as a promising target for cancer immunotherapy. However, progress in this field is blocked by limited knowledge regarding the ligands of γδ T cell receptors (TCR). Our project was driven by the idea that the acquisition of basic knowledge on γδ T cell biological functions could lead to new strategies for the elaboration of anti-viral and anti-tumor immunotherapies. So, our project aimed to boost research effort on this topic, on the basis of a work published by David Vermijlen (the promoter of the project). His group discovered a human γδ TCR which was highly enriched in every individual (therefore ‘public’) infected in utero with human cytomegalovirus (HCMV), and that reacts towards adult cancer cells, suggesting that it can detect signs of ‘cellular stress’ induced in both cell transformation and infection. Thus, the objective of this research project was the identification of the ligand of the public (cancer and infection) cross-reactive γδ TCR. Thanks to the work performed, it’s possible to conclude that: i) the ligand of the public γ TCR is not a soluble molecule; ii) about 150 genes that can represent candidate ligands were identified starting from previous gene expression profiling data; iii) a candidate ligand we selected from literature is not involved in the activation of the public TCR, thus it is not its ligand; iv) the immunoprecipitation protocols applied so far by using blocking antibodies were not able to provide us the expected results and support us in the identification of the ligand.

Data: CORDIS, © European Union

Project objective

gd T cells are the prototype of unconventional T cells and play an important role in the protection against infections and cancer. The group of David Vermijlen has recently discovered a human Vg8Vd1 T cell receptor (TCR) which was highly enriched in every individual (therfore ""public"") infected in utero with human cytomegalovirus (HCMV), and that reacts towards adult cancer cells, suggesting that it can detect signals of ""cellular stress"" induced in both infections and cell transformation. The major aim of this project is the identification of the ligand of this cross-reactive public Vg8Vd1 TCR. Two strategies will be adopted to address this aim. In the first strategy (indirect approach), a list of candidate ligands will be tested for the capacity to stimulate the TCR via functional assays. This list of genes is provided by gene expression profiling of target cells known to stimulate the public TCR (""stimulator cells"") verus non-stimulators, as well as from data in literature. In the second strategy (direct approach), in order to isolate or ""fish"" the ligand from a strong stimulator cell line we plan to adopt several methods, such as: i) production of blocking antibodies, ii) generation of ""gd bodies"", iii) proximity dependent biotinylation (BioID). The direct binding of promising ligand candidates with the public Vg8Vd1 TCR will be further investigated by surface plasmon resonance. Finally, in order to address the potential of this project for cancer immunotherapy we will evaluate the killing of primary cancer cells expressing the ligand by public Vg8Vd1-transduced PBMCs.The background of the MSCA applicant on HCMV-host interplay will highly complement the expertise of the group of David Vermijlen on gd T cells. As the public Vg8Vd1 TCR is present in every individual, the identification of its ligand will have broad implications as a possible target for the development of novel vaccination and cancer immunotherapy strategies.""

Original text from CORDIS.

Participants

  • UNIVERSITE LIBRE DE BRUXELLES · Bruxelles / BrusselCoordinatorBelgium

Links

Data: CORDIS, © European Union