Purification and identification of major soluble 40-kDa antigenic protein from Entamoeba histolytica: its application for serodiagnosis of asymptomatic amebiasis. |
| |
Authors: | J Sanuki K Nakano M Tokoro T Nozaki E Okuzawa S Kobayashi T Asai |
| |
Institution: | Department of Tropical Medicine and Parasitology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, 160-8582, Tokyo, Japan. |
| |
Abstract: | One of the major soluble antigenic proteins of Entamoeba histolytica was purified to homogeneity and identified on a molecular basis. Its recombinant protein was expressed in Escherichia coli as a fusion protein with Shistosoma japonicum glutathione S-transferase. Apparent molecular weight of the purified antigenic protein was estimated to be 40-kDa and molecular-based analysis indicated that the purified protein was NADP+-dependent alcohol dehydrogenase (EhADH1). The application of the purified protein for the serodiagnosis of amebiasis was evaluated using an enzyme-linked immunosorbent assay applied to sera obtained from patients with amebiasis and healthy human controls. The purified protein was well recognized by the sera from asymptomatic amebiasis humans (22/22, 100%), whereas, it was less recognized by the sera from symptomatic amebiasis patients (5/16, 31%) with amebic colitis or liver abscess. To confirm the antigenicity of EhADH1, the recombinant glutathione S-transferase-EhADH1 fusion protein was also evaluated by the enzyme-linked immunosorbent assay using the same sera. The recombinant protein was also recognized by the sera from asymptomatic amebiasis humans (14/22, 64%) and less recognized by the sera from symptomatic amebiasis patients (2/16, 13%). These results suggest that the purified protein is applicable antigen for serodiagnostic screening of asymptomatic amebiasis humans. |
| |
Keywords: | |
|
|