Lymphocyte-induced corneal neovascularization: a morphologic assessment.

Lymphocytes obtained from mesenteric lymph nodes of rabbits were stimulated in vitro by concanavalin A and injected into the corneas of allogeneic hosts. Controls were nonstimulated, killed, or autogeneic lymphocytes injected into the contralateral corneas. The stimulated cells were significantly better inducers of neovascular growth. Histologic observations of the vascularized corneas showing marked mononuclear reactions at the limbus, coupled with the requirement of allogenicity, suggest that there was immunologic recognition of the implanted cells. Stimulated allogeneic blast cells may amplify this host recognition by their elaboration of lymphokines or enhanced antigenicity. The apparent importance of allogenicity for the induction of vessel growth in these experiments may be significant in the pathogenesis tumor-induced or graft-related corneal neovascularization.