GZMB and angina unstable: Furthermore, peripheral blood mononuclear cells (PBMCs) from patients with unstable angina produced higher GrB levels than PBMCs from patients with stable angina, and PBMC-derived conditioned media induced apoptosis in cultured endothelial cells, supporting a possible role for GrB in atherosclerosis severity, possibly inducing vascular apoptosis in unstable angina (43).