Activation of human mucosal-associated invariant T cells induces CD40L-dependent maturation of monocyte-derived and primary dendritic cells — ASN Events
  1. Schedule
  2. Session 4: Antigen presentation and APC interactions
  3. Activation of human mucosal-associated invariant T cells induces CD40L-dependent maturation of monocyte-derived and primary dendritic cells

Activation of human mucosal-associated invariant T cells induces CD40L-dependent maturation of monocyte-derived and primary dendritic cells (#29)

Mariolina Salio 1 , Olivier Gasser 2 , Claudia Gonzalez-Lopez 1 , Natasha Veerapen 3 , Uzi Gileadi 1 , Giorgio Napolitani 1 , Regan Anderson 4 , Gavin Painter 4 , Gurdyal S Besra 3 , Ian F Hermans 2 5 , Vincenzo Cerundolo 1
  1. MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, Headington, Oxford, UK
  2. Malaghan Institute of Medical Research, School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
  3. School of Biosciences, University of Birmingham, Edgbaston, Birmingham, UK
  4. The Ferrier Research Institute, Victoria University of Wellington, Lower Hutt, New Zealand
  5. Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand

Mucosal-associated invariant T (MAIT) cells are innate T cells recognising intermediates of the vitamin B2 biosynthetic pathway presented by the monomorphic MR1 molecule. To date it remains unclear whether in addition to their cytolytic activity important in antimicrobial defence, MAIT cells have also immune-modulatory functions, which could enhance DC maturation. Here, we investigated the molecular mechanisms dictating the interactions between human MAIT cells and dendritic cells (DC) and demonstrate that human MAIT cells mature monocyte-derived and primary DC in an MR1- and CD40L-dependent manner. Furthermore, we show that MAIT cell derived signals synergise with microbial stimuli to induce secretion of bioactive IL-12 by DC. Activation of human MAIT cells in whole blood leads to MR1- and cytokine-dependent NK cell transactivation. Our results underscore an important property of MAIT cells, which can be of translational relevance to rapidly orchestrate adaptive immunity through DC maturation.