Monoclonal antibody to ICAM-1 prolongs murine heterotopic corneal allograft survival.

Graft rejection requires an initial interaction between donor antigen presenting cells (APC) and recipient T cells; an interaction known to involve a variety of cell surface molecules. We have been investigating an interaction involving two of these molecules: lymphocyte function associated antigen-1 (LFA-1) on the T cell and its ligand, intercellular adhesion molecule-1 (ICAM-1) on the APC, in an effort to assess the effect its interruption would have on the ability of the recipient to reject an allograft. A monoclonal antibody (MAb) against ICAM-1 was given peritransplant to mice with heterotopically grafted corneas. Mice were killed at various time points and the grafts taken for histological assessment of rejection. Mice treated with Mab have a delayed influx of cells into the graft site and marginally better graft viability to day 50 after transplantation compared to controls. These results suggest that it is possible to decrease rejection even with brief peritransplant treatment. This provides encouragement for further experiments using more extensive therapy.