Serum antibody responses to bovine retinal S-antigen and rod outer segments in proliferative diabetic retinopathy before and after argon laser photocoagulation.

Using the enzyme-linked immunosorbent assay, the serum antibody titers to bovine retinal S-antigen and rod outer segments in pre- and post-argon laser treated diabetic retinopathy patients were compared to each other and to the titers of age- and sex-matched normal controls. The increase in anti-S titer following the initial laser treatment gave a P less than 0.01 using the two-tailed paired Student's t-analysis as compared to the prelaser anti-S titer. Both pre- and post-laser anti-S titers were elevated over normal controls with P values of less than 0.02 and less than 0.001, respectively. Eight weeks after the initial laser treatment, anti-S titers began to decline approaching control levels 12 weeks later. No significant change was found between pre- and post-laser titers when rod outer segments were used as antigen although the pre- and post-laser titers were increased over normal controls with P values of less than 0.05 and less than 0.001, respectively. The release and possible alteration of retinal components following photocoagulation may account for the rise in anti-S titers, while the prephotocoagulation titers may be due to retinopathy-related photoreceptor cell alteration.