In vivo prevention of transplant arteriosclerosis by ex vivo-expanded human regulatory T cells.

Transplant arteriosclerosis is the hallmark of chronic allograft dysfunction (CAD) affecting transplanted organs in the long term. These fibroproliferative lesions lead to neointimal thickening of arteries in all transplanted allografts. Luminal narrowing then leads to graft ischemia and organ demise. To date, there are no known tolerance induction strategies that prevent transplant arteriosclerosis. Therefore, we designed this study to test the hypothesis that human regulatory T cells (T(reg) cells) expanded ex vivo can prevent transplant arteriosclerosis. Here we show the comparative capacity of T(reg) cells, sorted via two separate strategies, to prevent transplant arteriosclerosis in a clinically relevant chimeric humanized mouse system. We found that the in vivo development of transplant arteriosclerosis in human arteries was prevented by treatment of ex vivo-expanded human T(reg) cells. Additionally, we show that T(reg) cells sorted on the basis of low expression of CD127 provide a more potent therapy to conventional T(reg) cells. Our results demonstrate that human T(reg) cells can inhibit transplant arteriosclerosis by impairing effector function and graft infiltration. We anticipate our findings to serve as a foundation for the clinical development of therapeutics targeting transplant arteriosclerosis in both allograft transplantation and other immune-mediated causes of vasculopathy

Nephrogenic systemic fibrosis: concepts and perspectives Fibrose nefrogênica sistêmica: conceitos e perspectivas

Nephrogenic systemic fibrosis is a chronic, progressive condition that develops in some patients with renal impairment after exposure to gadolinium-based contrast agents used in magnetic resonance imaging. Thickening of the skin is typical, usually affecting the extremities. Visceral organs can also be affected. The diagnosis of the disease requires careful clinicopathological correlation. Treatment aims at restoring renal function, which is associated with delayed progression and, eventually, remission of skin changes. Reduction and prevention of nephrogenic systemic fibrosis cases are based on limiting the use of gadolinium-based contrast agents in patients with kidney disorders (especially in patients with advanced renal failure at stages 4 and 5), and restricting their use to situations in which they are essential to diagnosis/follow-up. Other than limiting exposure to gadolinium based contrast agents, no effective preventive methods have been reported. Due to increased awareness about the disease among radiologists and nephrologists, the incidence of nephrogenic systemic fibrosis is declining.<br>Fibrose nefrogênica sistêmica é condição crônica, progressiva, desenvolvida caracteristicamente em pacientes nefropatas após exposição a contrastes radiológicos que contenham gadolínio. O espessamento cutâneo é aspecto típico, envolvendo predominantemente as extremidades. Envolvimento visceral pode ocorrer. O diagnóstico da doença requer cuidadosa correlação clínico-patológica. O tratamento visa à restauração da função renal, que se associa ao retardo da progressão e, eventualmente, remissão das alterações cutâneas. A prevenção da ocorrência e redução da incidência baseiam-se na limitação do uso de contrastes à base de gadolínio em nefropatas (especialmente na insuficiência renal avançada em estágios 4 e 5), restringindo-os às condições nas quais seja imprescindível ao diagnóstico/acompanhamento. À exceção da restrição de exposição aos agentes de contraste a base de gadolínio, não há métodos preventivos efetivos relatados. Devido à ampla divulgação da doença entre radiologistas e nefrologistas, a incidência da fibrose nefrogênica sistêmica está em declínio