A practical guide to magnetic resonance vascular imaging: techniques and applications.

Magnetic resonance angiography is a technique used to image both central and peripheral arteries using contrast and noncontrast techniques. These techniques are similar in that a bright signal, which appears white within blood vessels, is generated and the background tissues, veins, and stationary tissues are dark. This allows for assessment of anatomy and vascular disease.

Aortic allograft vasculopathy is mediated by CD8(+) T cells in Cyclosporin A immunosuppressed mice.

We investigated the role of CD4(+) T cells and CD8(+) T cells in mediating allograft vasculopathy in Cyclosporin A (CyA) immunosuppressed mice. We first established that a dose of 50 mg/kg/d CyA was required to prevent acute rejection in C57BL/6 mice. CyA given at 50 mg/kg/d did not prevent allograft vasculopathy in either cardiac or aortic transplants in these mice.

Impairment of recipient cytolytic activity attenuates allograft vasculopathy.

We investigated the role of CD4+ and CD8+ T subsets as well as T cell cytolytic effector mechanisms in the aortic allograft model of allograft vasculopathy using CD4 and CD8 gene knockout mice (CD4(-/-), CD8(-/-)) and mice deficient in cytolytic effector pathways. Medial apoptosis at 2 weeks was reduced in CD8(-/-) mice and in mice where cytotoxic T cell activity was compromised. At 8 weeks, substantial medial damage was observed in wild-type (WT) and CD4(-/-) recipients but medial preservation was evident in CD8(-/-) mice and in mice with impaired cytotoxic T cell activity.

CD8+ T cells mediate aortic allograft vasculopathy by direct killing and an interferon-gamma-dependent indirect pathway.

Objective: Allograft vasculopathy (AV) has emerged as the major obstacle to long-term survival in clinical heart transplantation. Immune events are implicated in the development of AV, but the cellular and molecular mechanisms involved remain unclear. We sought to determine whether and by what mechanism CD8(+) T lymphocytes are able to generate AV in a murine aortic allograft model.