Carla Baan - Follicular T helper cells and humoral reactivity in kidney transplant patients

Antibody-mediated, humoral rejection has been recognized as a common cause of transplant dysfunction and is responsible for 30–50% of failed allografts. The production of antibody is dependent on instructions from memory CD4+ T helper cells that interact with antigen-specific B cells. Recently, a specialized T-cell subset has been identified—T follicular helper (Tfh) cells—which support activated B cells via interleukin (IL)-21 after binding to the IL-21 receptor expressed by these B cells. Therefore, neutralizing the IL-21 pathway will selectively inhibit the allogeneic IL-21-driven Tfh- and B-cell functions. However, little is known of the role of Tfh cells in alloreactivity. In this talk I will explain the role of Tfh cells in B-cell-mediated allogeneic responses by discussing their mechanisms of actions. In addition, the use of immunosuppressive agents that intervene in Tfh–B-cell interaction and consequently prevent or treat antibody mediated rejection in patients after transplantation will be addressed.

Intervenant

Carla C. Baan, PhD, is Professor and head of the Nephrology & Transplantation Laboratory at Erasmus Medical Center, University Hospital Rotterdam, The Netherlands. Dr Baan obtained her doctorate from Erasmus University, The Netherlands.  Her position involves the supervision of doctorate research related to the role of cytokines, regulatory T cells, B cells, cell therapy and immunosuppressive drugs in clinical organ transplantation. At the laboratory immunological tests to monitor pathways of donor directed reactivity are developed and used including multi-parameter flow cytometry/Facs sort and Elispot for T and B cell profiling, phosphospecific flow cytometry for the analysis of intracellular signaling pathways, tissue culture assays to measure antigen specific proliferation & cytotoxicity, GWAS and PCR for gene expression and epigenetics, and immunohistochemistry. The aim of this translational work is to titrate the immunosuppressive burden on our patients in such a way that side-effects (infections, malignancies, cardiovascular events) are kept at a minimum while at the same time rejection processes are prevented. Dr Baan has been the President of the European Society for Organ Transplantation (2011-2013) and is a member of the board of the International Society for Heart and Lung Transplantation. Currently, dr Baan is the Executive Editor basic sciences of the Transplantation Journal.

2^nd IGO meeting

La seconde édition des conférences organisées par le Labex IGO (IGO meeting) s’est déroulée les 21 et 22 avril 2016 à la Faculté de pharmacie de Nantes. Cette conférence a rassemblé 160 spécialistes de l’immunologie, de la transplantation et de l’oncologie. Des orateurs français et étrangers (USA, Grande-Bretagne, Pays-Bas, Espagne, Italie, Suisse) sont venus exposer leurs travaux et les dernières avancées dans leurs domaines de recherche. Des sessions (communications orales et posters) étaient également réservées aux jeunes chercheurs pour qu’ils puissent présenter leurs travaux et ainsi favoriser les échanges avec leurs collègues et les chercheurs séniors. Ce 2^nd IGO meeting, en créant un environnement propice à l’initiation de nouvelles collaborations à l’intérieur et au-delà du périmètre du Labex IGO, a été un vrai succès scientifique.