Possible pathogenic role of the transmembrane isoform of CD160 NK lymphocyte receptor in paroxysmal nocturnal hemoglobinuria.
Giustiniani J, Alaoui SS, Marie-Cardine A, Olive D, Bos C, Razafindratsita A, Petropoulou A, de Latour RP, Le Bouteiller P, Bagot M, Socié G, Bensussan A
PIGA mutations in paroxysmal nocturnal hemoglobinuria (PNH) patients lead to a glycosylphosphatidylinositol (GPI)-linked membrane proteins expression deficiency. Herein, we report the constitutive expression of the transmembrane CD160 (CD160-TM) activating receptor on non PIGA-mutated PNH patients circulating NK cells. In healthy individuals, only the GPI-anchored isoform of CD160 receptors is expressed on the circulating NK lymphocytes, while the transmembrane isoform appears after ex vivo activation. Similarly to CD160-GPI, we identified CD160-TM as a receptor for the MHC class I molecules. We demonstrate that PNH patients NK lymphocytes spontaneously produce significant amounts of IFN-γ that is inhibited by anti-CD160-TM or anti-MHC class I mAbs. These results indicate that circulating NK cells from PNH patients exhibit a self-MHC class I molecule reactive effector function, which could be mediated through the recruitment of CD160-TM receptor. Our data provide new insights regarding the possible role of CD160-TM on PNH patients NK lymphocytes and in the pathogenesis of the disease.Lire l‘article