AN EXPERIMENTAL-MODEL FOR INFILTRATION OF MALIGNANT-LYMPHOMA TO THE EYE AND BRAIN

Currently there is no adequate experimental model available whereby th e lethal infiltration of malignant lymphoma to the eye and CNS can be studied. Variant S49 mouse lymphoma cells that exhibit cell-cell adhes ion properties (named Rev-2-T-6) were inoculated intraperitoneally int o Balb/C mice at the ages of 6-60 days postnatal. Mice inoculated betw een days 6-11 postnatal developed signs of eye and CNS involvement wit h an apparent peak (58% of mice) at day 7. None of the mice inoculated beyond day 11 exhibited such signs. Histological analysis of these si tes revealed tumorous infiltrates into a variety of structures in the orbit, intraocular tissues, along the optic nerve and in the brain. Ad ditional analysis of the histopathological data, based on the structur es demonstrating the highest frequency of lymphoma infiltration, sugge sts preferred routes of lymphoma entry to the brain and eye. Thus, ent ry to the brain can occur mainly through the choroid plexus and crania l nerves or cranial nerve ganglia. Entry to the eye may occur from the brain (along the optic nerve), and through hematogenous infiltration of orbital structures. No data were found that would support retrograd e infiltration of the lymphoma from the eye to the brain. These findin gs present an experimental model for addressing the molecular mechanis ms that govern homing of malignant lymphoma to the eye and brain, as w ell as the development of experimental therapeutic modalities for mali gnant lymphoma in these organs.