Frequency of Anti-Retinal Antibodies in Normal Human Serum

Abstract

The presence of anti-retinal antibodies is observed in a majority of normal control human sera, suggesting that identification of new candidate retinal autoantigens should be cautiously interpreted and subject to rigorous testing for disease association. Additional studies will aid development of a standardized protocol for validation of potential pathogenic seroreactivity.

Autoimmune Retinopathy

“…Masking of laboratory personnel to patient diagnosis has not been consistently reported. Different labs have varied in the species origin of the retinal protein extracts, the methods of protein extraction and their definition of positive reactivity [30]. Studies have frequently used bovine, rodent and monkey tissue in assays on account of the difficulty of obtaining fresh cadaveric human retinal tissue samples.…”

“…A recent study on 92 samples of laboratory ‘normal control’ human sera revealed that 62% of serum samples had antiretinal IgG immunoreactivity to solubilized human retinal proteins [30]. Western blot analysis detected reactivity against a few retinal protein bands in 33%, and against 5 or more retinal protein bands in 22%, ranging in weight from 13 to 148 kDa [30]. Autoantibodies have been found in numerous other retinal and systemic diseases, and in patients with cancer but no visual symptoms [50,51].…”

Slowly progressive non-neoplastic autoimmune-like retinopathy

“…Although we performed WB analysis against one of the possible candidate photoreceptor-specific proteins, beta-3 subunit of guanine nucleotide protein [8], positive immunoreactivity was not found (data not shown). Thus, we must consider that this possible antibody developed during the course of the disease process, or developed independently [9]. Further investigations, including the identification of these retinaspecific antigens by mass spectrometry, are needed to characterize the antibodies associated with slowly progressive AIR.…”

The Enigma of Autoimmune Retinopathy

“…However, the pathogenicity of other retinal autoantibodies has not been so well studied. Using Western blot techniques, Shimazaki et al 32 have shown that 33% of normal human serum demonstrates 1 to 2 bands, and 22% of normal human serum contains ≥5 bands. Given the numerous putative retinal autoantibodies that have been described, and the fact that normal serum can have significant antiretinal antibody activity, it is of paramount importance to definitively prove the pathogenicity of the autoantibodies suspected of causing AIR.…”