Molecular Landscape of Microvascular Inflammation in Kidney Allografts

Antibody-mediated rejection is a major cause of graft failure in kidney transplant recipients. The diagnostic criteria for antibody-mediated rejection have undergone significant changes since their initial definition in the international Banff Classification system. The Banff 2022 Classification update reappraises lesions of microvascular inflammation and identifies new phenotypes for cases with microvascular inflammation. However, pathophysiological mechanisms associated with microvascular inflammation in kidney allografts are still poorly understood, thus hampering the development of efficient treatments. The aims of this study are: 1. To decipher the spatial immune-molecular landscape of microvascular inflammation in kidney allografts. 2. To compare the characteristics of this landscape in different clinical scenarios. The investigators will use a multimodal phenotyping approach including histological analyses and multiplex immunostainings, bulk transcriptomic analyses and spatial whole-transcriptome digital profiling to decipher the molecular landscape of microvascular inflammation in kidney allografts. Based on these results, they will investigate its association with allograft outcomes and search for molecular targets which could benefit from targeted therapeutic strategies.