The choroid plexus in passive serum sickness.

Immunofluorescent microscopy of the choroid plexus revealed the presence of rabbit IgG and either rat or mouse C3 in a high percentage of young male Wistar rats and CF1 mice who had received intravenous injections of preformed BSA-rabbit anti BSA complexes over a 3 day period. Electron dense deposits were observed in the basement membrane region of the choroid plexus in these animals. These findings were comparable to those noted in their renal glomeruli. This is the first description of involvement of the choroid plexus in passive immune complex disease. This experimental model is rapidly inducible and should be of value in future pathophysiological studies of this important structure.