| First Author | Shimizu K | Year | 2008 |
| Journal | Circulation | Volume | 117 |
| Issue | 15 | Pages | 1997-2008 |
| PubMed ID | 18378617 | Mgi Jnum | J:153298 |
| Mgi Id | MGI:4361968 | Doi | 10.1161/CIRCULATIONAHA.107.724310 |
| Citation | Shimizu K, et al. (2008) Leukocyte integrin Mac-1 promotes acute cardiac allograft rejection. Circulation 117(15):1997-2008 |
| abstractText | BACKGROUND: In allograft rejection, recipient leukocytes and alloantibodies first target donor endothelial cells. Although the leukocyte integrin Mac-1 (alpha(Mbeta2), CD11b/CD18) facilitates cell-cell interactions among leukocytes and interactions between leukocytes and endothelial cells or platelets, its role in allograft survival and vasculopathy is incompletely defined. METHODS AND RESULTS: This study examined parenchymal rejection and graft arterial disease after total allomismatched cardiac transplantation (BALB/c donor heart and B6 recipients) in wild-type (WT) and Mac-1-deficient (Mac-1(-/-)) recipients. Recipient Mac-1 deficiency attenuated parenchymal rejection and significantly prolonged cardiac allograft survival from 8.3+/-1.3 days in WT recipient allografts (n=18) to 13.8+/-2.3 days in Mac-1(-/-) recipient allografts (n=6; P<0.0001). Accumulation of neutrophils and macrophages significantly decreased in Mac-1(-/-) compared with WT recipients. Adoptive transfer of WT but not Mac-1(-/-) macrophages to Mac-1(-/-) recipients exacerbated parenchymal rejection and reduced allograft survival; in contrast, adoptive transfer of WT neutrophils did not affect graft survival. Mac-1(-/-) macrophages expressed significantly lower levels of costimulatory molecules both in vivo and in vitro, and mixed lymphocyte reaction using alloantigen-primed Mac-1(-/-) macrophages resulted in significantly lower antigen-presenting function than for WT macrophages. Tumor necrosis factor-alpha production also fell in cultures with Mac-1(-/-) macrophages. Despite attenuation of acute rejection, recipient Mac-1-deficiency did not prevent late graft arterial disease. CONCLUSIONS: These studies demonstrate critical participation of Mac-1 in alloresponses during cellular allograft rejection. These observations establish a molecular target for modulating recipient responses to prolong graft survival. |
