TNFRSF9 and atherosclerosis: In contrast, vein graft atherosclerosis is characterized by an additional period of highly acute, high-grade inflammation caused by surgical injury and perturbed hemodynamics.50, 51, 52, 53 Moreover, the expression of CD137 and CD69 at t = 1d suggests surgery-related activation of T-cells, because the earliest signs of foam cell/atherosclerotic plaque formation are observed at t = 7d.54