Depletion of T regulatory cells promotes natural killer cell-mediated cardiac allograft vasculopathy.

Background: A role for natural killer (NK) cells in cardiac allograft vasculopathy (CAV) was suggested by our earlier observation that CAV arises even in the absence of detectable antidonor T-cell or B-cell reactivity in parental to F1 mouse heart grafts. However, prevention of CAV in this setting required the depletion of both NK and CD4 T cells.

Methods: To clarify the interrelationship between NK and CD4 cells, we analyzed early events and selective depletion of T regulatory cells (Tregs).