Abstract: Objective: To investigate the associations between the levels of human plasma anti-gliadin antibodies and occurrence of schizophrenia in the patients with different ages in Chinese Han population,and to clarify the effects of human plasma anti-gliadin antibodies in the occurrence of schizophrenia.Methods: The plasma samples were collected from 313 schizophrenia patients (schizophrenia group) and 408 healthy controls (healthy control group) in Chinese Han population. The levels of human anti-gliadin IgA and IgG antibodies of the subjects in various groups were detected by enzyme-linked immnosorbent assay(ELISA) method. The levels of human plasma anti-gliadin IgA and IgG antibodies in the subjects in schizophrenia group and healthy control group were analyzed by Pearson's correlation analysis and compared by Mann-Whitney U test; receiver operating characteristic (ROC) curve analysis was performed.Results: The level of plasma anti-gliadin IgA antibody showed a significantly positive correlation with the age and age ranges of the subjects(r=0.177,P<0.01;r=0.171,P<0.01); the level of plasma anti-gliadin IgG antibody showed significantly negative correlation with the age and age ranges of the subjects (r=-0.104, P<0.01;r=-0.127, P<0.01).Compared with healthy control group, the levels of plasma anti-gliadin IgA antibodies of the patients aged 20-30 years old and 50-60 years old in schizophrenia group were increased(Z=-3.746,P<0.01;Z=-2.186,P<0.05). Compared with healthy control group, the level of plasma anti-gliadin IgG antibody of the patients aged 20-30 years old in schizophrenia group was increased, but the difference was not statistically significant(P>0.05). The ROC curve analysis results showed that the area under ROC curve(AUC) of anti-gliadin IgA and IgG antibodies were 0.573 (SE=0.022, 95%CI:0.53-0.62) and 0.520 (SE=0.022, 95%CI:0.48-0.56). The sensitivities of anti-gliadin IgA and IgG antibodies were 13.7% and 12.8% when the specificity was 92.2%.Conclusion: The increasing of plasma anti-gliadin antibodies level is associated with the occurrence of schizophrenia in the patients with different age ranges in Chinese Han population, and the human plasma anti-gliadin antibodies maybe play an important role in the young schizophrenia patients.

Key words: schizophrenia, gliadin, anti-gliadin IgA antibody, anti-gliadin IgG antibody, enzyme-linked immunosorbent assay