CD8 super(+) T Lymphocytes Regulate the Arteriogenic Response to Ischemia by Infiltrating the Site of Collateral Vessel Development and Recruiting CD4 super(+) Mononuclear Cells Through the Expression of Interleukin-16

BACKGROUND: Previous studies have demonstrated that macrophages and CD4 super(+) T lymphocytes play pivotal roles in collateral development. Indirect evidence suggests that CD8 super(+) T cells also play a role. Thus, after acute cerebral ischemia, CD8 super(+) T cells infiltrate the perivascular space and secrete interleukin-16 (IL-16), a potent chemoattractant for monocytes and CD4 super(+) T cells. We tested whether CD8 super(+) T lymphocytes contribute to collateral vessel development and whether the lack of circulating CD8 super(+) T cells prevents IL-16 expression, impairs CD4 super(+) mononuclear cell recruitment, and reduces collateral vessel growth after femoral artery ligation in CD8 super(-/-) mice. METHOD:S: and Results- After surgical excision of the femoral artery, laser Doppler perfusion imaging demonstrated reduced blood flow recovery in CD8 super(-/-) mice compared with C57/BL6 mice (ischemic/nonischemic limb at day 28, 0.66 plus or minus 0.04 versus 0.87 plus or minus 0.04, respectively; P