Increased frequency of anti-retina antibodies in asymptomatic patients with chronic t. gondii infection.
OBJECTIVE
To search for anti-retina antibodies that serve as markers for eye disease in uveitis.


METHODS
Stored sera from patients with uveitis, ocular toxoplasmosis (n = 30) and non-infectious, immune-mediated uveitis (n = 50) and from asymptomatic individuals who were positive (n = 250) and negative (n = 250) for anti-Toxoplasma antibodies were tested. Serum anti-retina IgG was detected by an optimized ELISA using a solid-phase whole human retina extract, bovine S-antigen or interphotoreceptor retinoid-binding protein.


RESULTS
Uveitis patients showed a higher mean reactivity to whole human retina extract, interphotoreceptor retinoid-binding protein and S-antigen in comparison to the asymptomatic population. These findings were independent of the uveitis origin and allowed the determination of the lower anti-retina antibody cut-off for the three antigens. Asymptomatic anti-Toxoplasma serum-positive individuals showed a higher frequency of antihuman whole retina extract antibodies in comparison to asymptomatic anti-Toxoplasma serum-negative patients. The bovine S-antigen and interphotoreceptor retinoid-binding protein ELISAs also showed a higher mean reactivity in the uveitis groups compared to the asymptomatic group, but the observed reactivities were lower and overlapped without discrimination.


CONCLUSIONS
We detected higher levels of anti-retina antibodies in uveitis patients and in a small fraction of asymptomatic patients with chronic toxoplasmosis. The presence of anti-retina antibodies in sera might be a marker of eye disease in asymptomatic patients, especially when whole human retina extract is used in a solid-phase ELISA.
Protozoology Department, Instituto de Medicina Tropical de São Paulo, São Paulo, SP, Brazil.
Sylvia Regina Temer
SR
Cursino
Thaís Boccia da
TB
Costa
Joyce Hisae
JH
Yamamoto
Luciana Regina
LR
Meireles
Maria Antonieta Longo Galvão
MA
Silva
Heitor Franco de
HF
Andrade Junior
D000704:Analysis of Variance; D000941:Antigens / Q000276:immunology; D058345:Asymptomatic Infections; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D012160:Retina / Q000276:immunology*; D018709:Statistics, Nonparametric; D014123:Toxoplasmosis / Q000150:complications* / Q000276:immunology; D014126:Toxoplasmosis, Ocular / Q000175:diagnosis* / Q000209:etiology; D014605:Uveitis / Q000175:diagnosis* / Q000209:etiology
D000941:Antigens; D001323:Autoantibodies; D015415:Biomarkers; D007074:Immunoglobulin G