title: Cell-mediated immunity in F 344 rats bearing intraocular tumors derived from human adenovirus 12-induced retinal tumor.
abstract: The eyes of 10 F344 rats were inoculated with retinal tumor cells (EXP-5 cell line) induced by human adenovirus 12. The animals were killed at 4 weeks thereafter, and the cytotoxicity of their lymphocytes was investigated by using 51Cr-releasing assay. The percentage of EXP-5 cells killed in vitro by lymphocytes was higher in 10 rats with ocular tumors (24.6% +/- 6.1%, mean +/- SD) than in 10 control rats (6.2% +/- 1.8%). Morphologic investigation using syngeneic spleen cells confirmed the presence of lymphoid cells, resembling T-lymphocytes, adhering to EXP-5 cells. The influence of subcutaneous injection of EXP-5 cells on the growth of intravitreously injected tumor cells was investigated. Cells injected subcutaneously prior to intravitreous injection elicited an immune response that was capable of controlling vitreous tumor growth. These findings suggest that the rats with transplanted retinal tumors develop a cell-mediated immune response in the early stage of tumor bearing, and that a state of pre-existing specific immunity can overcome so-called "immunologic privilege" of the vitreous body.
mesh_terms: D000260:Adenoviruses, Human; D000818:Animals; D003602:Cytotoxicity, Immunologic; D005134:Eye Neoplasms / Q000209:etiology / Q000276:immunology* / Q000473:pathology; D005260:Female; D007111:Immunity, Cellular; D008214:Lymphocytes / Q000276:immunology; D051381:Rats; D011916:Rats, Inbred F344; D012175:Retinoblastoma / Q000209:etiology / Q000276:immunology* / Q000473:pathology; D014822:Vitreous Body / Q000276:immunology / Q000473:pathology