The immunopathophysiological effects of chronic serum sickness on rat choroid plexus, ciliary process and renal glomeruli.

The immunopathological findings and their effects upon the vascular permeability of the ciliary process, choroid plexus and renal glomeruli to intravenously injected 125I-bovine serum albumin (BSA) have been studied in 26 rats who survived a prolonged period of bovine serum albuminemia following the experimental chronic serum sickness model of Fennell and Pardo (8). Rat IgG and C3 and BSA were demonstrated in the experimental rats by direct immunofluorescence in glomeruli, ciliary process and choroid plexus of 85, 38 and 39 percent of animals respectively. Age and sex matched control tissues were negative. Statistically significant differences in the 125I-BSA content of urine, eye and brain were observed between the experimental and control groups. This experimental model offers an approach to the understanding of ocular and central nervous system involvement in clinical situations characterized by circulating immune complexes as well as an experimental tool with which to explore further the physiological consequences of immune deposits within the choroid plexus and ciliary body.