Defective expression and function of natural killer cell-triggering receptors in patients with acute myeloid leukemia.

摘要: The cytolytic function of natural killer (NK) cells is induced by the engagement a series activating receptors and coreceptors some which have recently been identified collectively termed cytotoxicity (NCRs). Here, we analyzed NK obtained from patients with acute myeloid leukemia (AML). In sharp contrast healthy donors, in most (16 18) AML majority displayed low NCR surface density (NCRdull). This phenotype correlated weak activity against autologous leukemic that could not be reversed monoclonal antibody-mediated disruption HLA class I/killer immunoglobulinlike receptor interaction. remaining 2 were characterized having an NCRbright phenotype. Surprisingly, although displaying NCR-mediated activity, these unable to kill blasts. Importantly, blasts also resistant lysis mediated normal NCRbrightallogeneic cells. Our study suggests instances inability consequent expression. few cases, however, this failure appears involve mechanism tumor escape based on down-regulation ligands relevant for target cell recognition.