Profiles ofEntamoeba histolytica-specific immunoglobulins in human sera

摘要

Objective:To determine the profiles of anti-Entamoeba histolytica(E. histolytica) IgA, IgG, and IgM in sera of diarrheic and non-diarrheic individuals and partially characterize target antigens.Methods:Serum samples from thirty diarrheic and thirty non-diarrheic individuals were subjected to IgA, IgG, and IgM profiling through enzyme-linked immunosorbent assay (ELISA), flow cytometry, and immunoblot.Results:ELISA titer results showed that both diarrheic and non-diarrheic individuals possess high levels ofE. histolytica-specific IgG compared to IgA and IgM. Flow cytometry data showed that diarrheic serum samples had higher mean reaction percentages againstE. histolyticacells compared to non-diarrheic samples. Immunoreactive E.histolytica proteins with molecular weights ranging between7 kDa and 292 kDa were recognized by diarrheic serum IgG, and170 kDa and250 kDa by non-diarrheic serum IgG. Conclusions: Our findings suggest that serum anti-E. histolyticaIgG, compared with serum anti-E. histolytica IgA and IgM responses, was generally high in both diarrheic and non-diarrheic sera, indicating a past exposure to the organism both in symptomatic patients as well as in asymptomatic carriers, respectively. In addition, serum IgG from diarrheic and non-diarrheic patients were able to detect immunogenicE. histolytica proteins.