Antibodies to neurofilament protein in retinitis pigmentosa.

Antibodies reactive with heterologous neural tissue were detected by indirect immunofluorescence microscopy in the sera of 17 of 34 patients with retinitis pigmentosa, one of 30 normal control sera, and a variable percentage of sera derived from subjects with diverse ocular and neurological diseases. These antibodies were also found both in disease-free first degree relatives and in spouses of patients with retinitis pigmentosa. Analytical sodium dodecyl sulfate-polyacrylamide gel electrophoresis of human spinal cord components followed by immunoblots with sera under study revealed that the serum antibody was specific for the high molecular weight protein subunit of neurofilaments. No correlation was found between the presence of these antibodies and other immunological and clinical parameters in retinitis pigmentosa. These findings suggest that release of piled-up neurofilaments from damaged neurones in retinitis pigmentosa triggers B lymphocytes autoreactive to neurofilament antigens.