Immunology of corneal allograft rejection: in vitro sensitization of effector cells

Anterior chamber injection of donor rabbit lymphocytes sensitized in vitro to recipient alloantigens leads to the development of small focal areas of endothelial cell destruction (pocks) on the recipient cornea. Damage may be observed through a specular microscope as early as 2 days after injection of sensitized lymphocytes. Recipients of unsensitized allogeneic or sensitized autologous lymphocytes demonstrate little or no endothelial damage and no pock formation. Flat endothelial preparations reveal focal destruction of the endothelium with multiple foci, many infiltrated and surrounded by mononuclear cells. This model provides controlled sensitization to a variety of histocompatibility and corneal antigens that may be responsible for initiation of graft rejection.