On the significance of the phacoautoantibodies demonstrated in the sera of patients with senile cataract.

Serum was obtained from fifty-one patients before operation for senile cataract. Individual extracts were prepared from the excised lenses and were used as autologous antigens in complement-fixation and precipitin tests upon the patients' sera. The complement-fixation test was positive with forty-three of the fifty-one sera and the precipitin tests with twenty-seven out of forty-five of the sera tested by this method. The incidence of both antibodies was higher in patients with cataract of relatively long duration, but complement-fixing antibody of titre 1:32 or more appears to develop earlier during the course of the disease than positive precipitin tests. The incidence of complement-fixation antibody was also relatively high in patients undergoing operation for a second cataract. No obvious correlation was observed between the two antibodies in individual sera but the most strongly positive precipitin reactions tended to be associated with negative or low titre complement-fixation tests. Serum from forty individuals without eye disease were also tested, using as antigen a pooled extract of many lenses; the results were completely negative.