title: Serological differentiation of acute and chronic schistosomiasis using Schistosoma mansoni recombinant protein RP26.
abstract: We obtained a recombinant protein encoded by Schistosoma mansoni gene which was able to differentiate acute from chronic schistosomiasis when applied as antigen in enzyme-linked immunosorbent assay (ELISA). A cDNA clone encoding a 26 kDa recombinant protein (RP26) was selected by screening of an adult worm S. mansoni lambdaZAP expression library with rabbit sera produced against PIII, an adult worm protein fraction already known to possess protective and immunomodulating effects. The clone cDNA presented 99% identity with S. mansoni Sm22.3 gene. We assayed IgG reactivity of sera from 18 patients with acute, 25 patients with chronic S. mansoni infection and 20 uninfected donors with RP26 in ELISA. Our results showed that 89% of sera were positive in acute schistosomiasis group, and only 26% in chronic group, without false-positive reactions in uninfected group. In mice the immune response to RP26 increased up to week 9 after infection and then diminished. We proposed that production of antibodies binding to RP26 stopped at the chronic stage of disease. The testing of sera from eight other parasitic infections with RP26 revealed no positive reactions in majority of sera. However, we observed low positive reaction in sera from 20% of leishmaniasis patients. Our results indicate that a recombinant protein RP26 can be used as immunodiagnostic reagent for detection of acute phase of schistosomiasis mansoni.
authors.affiliation: Laboratory of Molecular Biology, Institute of Biochemistry, Russian Academy of Medical Sciences, Novosibirsk, Russia.
authors.forename: E
authors.initials: E
authors.lastname: Makarova
authors.forename: T S
authors.initials: TS
authors.lastname: Goes
authors.forename: A L M
authors.initials: AL
authors.lastname: Marcatto
authors.forename: M F
authors.initials: MF
authors.lastname: Leite
authors.forename: A M
authors.initials: AM
authors.lastname: Goes
mesh_terms: D000208:Acute Disease; D000595:Amino Acid Sequence; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D002908:Chronic Disease; D003937:Diagnosis, Differential; D004195:Disease Models, Animal; D005189:False Positive Reactions; D005260:Female; D015801:Helminth Proteins / Q000097:blood* / Q000737:chemistry; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D011817:Rabbits; D011994:Recombinant Proteins / Q000276:immunology; D012555:Schistosomiasis mansoni / Q000175:diagnosis*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D000909:Antibodies, Helminth; D015801:Helminth Proteins; D007074:Immunoglobulin G; D011994:Recombinant Proteins