Proc Natl Acad Sci U S A. 2005 May 17;102(20):7251-6. Epub 2005 May 6.

Interleukin 10 attenuates neointimal proliferation and inflammation in aortic allografts by a heme oxygenase-dependent pathway.

Chen S, Kapturczak MH, Wasserfall C, Glushakova OY, Campbell-Thompson M, Deshane JS, Joseph R, Cruz PE, Hauswirth WW, Madsen KM, Croker BP, Berns KI, Atkinson MA, Flotte TR, Tisher CC, Agarwal A.

Source

Department of Medicine, Nephrology Research and Training Center, University of Alabama at Birmingham, Birmingham, AL 35294.

Abstract

Interleukin 10 (IL-10) is a pleiotropic cytokine with well known antiinflammatory, immunosuppressive, and immunostimulatory properties. Chronic allograft rejection, characterized by vascular neointimal proliferation, is a major cause of organ transplant loss, particularly in heart and kidney transplant recipients. In a Dark Agouti to Lewis rat model of aortic transplantation, we evaluated the effects of a single intramuscular injection of a recombinant adeno-associated viral vector (serotype 1) encoding IL-10 (rAAV1-IL-10) on neointimal proliferation and inflammation. rAAV1-IL-10 treatment resulted in a significant reduction of neointimal proliferation and graft infiltration with macrophages and T and B lymphocytes. The mechanism underlying the protective effects of IL-10 in aortic allografts involved heme oxygenase 1 (HO-1) because inhibition of HO activity reversed not only neointimal proliferation but also inflammatory cell infiltration. Our results indicate that IL-10 attenuates neointimal proliferation and inflammatory infiltration and strongly imply that HO-1 is an important intermediary through which IL-10 regulates the inflammatory responses associated with chronic vascular rejection.