B-cell specific expression of the murineMyd88L252Pmutation correlates with the establishment of an immunosuppressive microenvironnement in Waldenström macroglobulinemia lymphoplasmacytic lymphoma

Waldenström macroglobulinemia is a rare and indolent lymphoproliferative disorder genetically characterized by the presence of the L265P mutation in the MYD88 gene in nearly each case. Despite its slow progression, Waldenström macroglobulinemia remain incurable due to the lack of specific treatments. The importance of the tumour microenvironment was well documented since the last decade especially concerning the study of solid tumours, but the failures of the immune microenvironment are also experiencing growing interest for B cell lymphomas. In this study, we investigated the implication of some dysregulations of the immune microenvironment in Waldenström macroglobulinemia through our Myd88 L252P mutated transgenic model, which may explain its progression. In essence, we highlighted the existence of multiple immune escape mechanisms that lead to T-cell exhaustion and participate to Waldenström disease progression. This work in animals opens up new prospects for the development of new therapeutic combinations in WM targeting reactivation of the immune system.