Inhibition of accelerated coronary atherosclerosis with short-term blockade of intercellular adhesion molecule-1 and lymphocyte function-associated antigen-1 in a heterotopic murine model of heart transplantation.

BACKGROUND: Graft arteriopathy limits the long-term survival of allograft recipients. Cardiac allografts in mice develop graft coronary arteriopathy similar to that observed in clinical chronic rejection in human beings. We found that antiintercellular adhesion molecule-1 (ICAM-1) and antilymphocyte function-associated antigen-1 (LFA-1) monoclonal antibodies (mAbs) induce immunologic tolerance to mice with cardiac allografts.
METHODS: To evaluate the effects of short-term administration of anti-ICAM-1 plus anti-LFA-1 mAbs in preventing graft arteriopathy, we treated C3H/He mice that received cardiac allografts from BALB/c mice with anti-ICAM-1 plus anti-LFA-1 mAbs for the first 5 days after transplantation. For control studies, FK506 was administered daily to other allograft recipients. Allografts were harvested on day 60. Immunohistochemical analysis was used to detect the expression of ICAM-1 and vascular cell adhesion molecule (VCAM)-1, and in situ reverse transcriptase polymerase chain reaction was performed to detect platelet-derived growth factor (PDGF)-B mRNA expression in the graft arteries.
RESULTS: Allografts from mice that received FK506 treatment daily showed significant neointimal thickening with increased expression of ICAM-1, VCAM-1, and PDGF-B mRNA, whereas there was almost no intimal thickening and ICAM-1, VCAM-1, and PDGF-B mRNA expression in the mice that received anti-ICAM-1 plus anti-LFA-1 mAbs.
CONCLUSION: Short-term blockade of ICAM-1 and LFA-1 adhesion not only induces immunologic tolerance to cardiac allografts but also prevents graft arteriopathy.