VISICORT researchers Nicolas Degauque and Sophie Brouard from INSERM UMR1064 and Université de Nantes (France) have recently published two articles which were supported in part through the VISICORT project.
A review of cross-reactivity of the TCR repertoire has been published in the Journal Frontiers in Immunology and looks at the implications of cross-reactivity for allotransplantation. The ability to track donor reactive T cells during organ transplantation can improve graft survival, prevent graft dysfunction and help in tailoring immunosuppressive treatment and is therefore of great advantage to transplant immunologists. However the vast size of the alloreactive T cell repertoire has hampered attempts in this area. The authors review progress in this area including the evolution of the concept of cross-reactivity of the TCR repertoire and the development of techniques to track anti-donor response. It is now expected that each T cell can recognise a large array of peptides (cross-reactivity) resulting in more efficient immunological protection for individuals. The necessity of TCR cross-reactivity is explored using allotransplantation as a functional and efficient example. The benefits of using low resolution techniques such as PCR and flow cytometry or high resolution techniques such as next generation sequencing to track anti-donor response via the TCR Vβ repertoire is also summarised in the review article. Effective donor-specific T cell tracking has not yet been translated to the clinical management of transplant patients despite advances in the area.
In a separate article, a brief communication published in the American Journal of Transplantation, the similarities and differences of three subsets of CD8 T cells were investigated from peripheral blood mononuclear cell (PBMC) samples of kidney transplant patients with stable grafts on standard immunosuppressive regimes. CD8 cells have long been implicated in transplant rejection and memory cells are considered one of the main hurdles in achieving transplantation success. Bearing in mind both assay functionality and limitations with flow cytometry techniques, it is important to choose the right CD8 markers for specific studies. The article reported on the use of CD45RA and CCR7/ CD27/ CD28 markers to identify CD8 subsets. The authors found that use of CD45RA and CD28 markers offer several benefits for characterisation of the CD8 compartment in kidney transplant patients including the identification of early and late differentiated Effector Memory CD8 T cells.
Speaking on the two articles and their relation to VISICORT Dr Degauque said “VISICORT represents a unique opportunity to compare the imprint on the immune systems induced by two different types of transplantations (Kidney or Corneal Transplantation), by looking at the selection of the TCR to the modification of the phenotype of T cells. The monitoring of large clinical cohorts requires the use of multi-colour flow cytometry panels in which the numbers of the tracked markers will define the accuracy of the depiction of the immune system. Using advanced multicolour panels, we aim to improve our understanding of the adaptive immune cells in corneal rejection and to identify biomarker of graft rejection in order to improve patients standard care.”
The full text of the article in Frontiers in Immunology can be found here. Work on VISICORT work packages 4 and 5 is continuing at INSERM UMR1064 and Université de Nantes.