title: Recombinant cDNA clones for immunodiagnosis of strongyloidiasis.
abstract: Because diagnosis of strongyloidiasis by stool examination is unreliable and because of the potential for serious disease in Strongyloides infections, there is need for improved diagnostic aids to facilitate recognition and treatment of this parasitic infection. Serologic testing, when available, requires antigen preparation from infected primates or dogs that can be difficult to maintain. Several recombinant clones from a cDNA library prepared from the infective stage of Strongyloides stercoralis were characterized. Serologic results indicate that the recombinant proteins were equally or more reactive than the larval somatic antigen. No cross-reactivity with recombinant antigen 5a was found with sera from patients with filarial or intestinal nematode infections. Recombinant antigens 5a and 12a detected parasite-specific IgE and IgG4 antibodies in Strongyloides-infected patients. Sequence analysis showed these antigens to be rich in proline and charged amino acids. Lack of homology from database searches suggests that the antigens are unique. These recombinant antigens should be useful in diagnostic and epidemiologic studies of strongyloidiasis.
authors.affiliation: Laboratory of Parasitic Diseases, National Institutes of Health, and Center for Biologics Evaluation, Food and Drug Administration, Bethesda, Maryland 20892, USA.
authors.forename: S
authors.initials: S
authors.lastname: Ramachandran
authors.forename: R W
authors.initials: RW
authors.lastname: Thompson
authors.forename: A A
authors.initials: AA
authors.lastname: Gam
authors.forename: F A
authors.initials: FA
authors.lastname: Neva
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000909:Antibodies, Helminth / Q000032:analysis / Q000276:immunology; D000947:Antigens, Helminth / Q000276:immunology; D001483:Base Sequence; D015153:Blotting, Western; D003429:Cross Reactions / Q000276:immunology; D018076:DNA, Complementary / Q000235:genetics; D018509:DNA, Helminth / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression; D015723:Gene Library; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis / Q000276:immunology; D007074:Immunoglobulin G / Q000032:analysis / Q000276:immunology; D007814:Larva / Q000276:immunology; D008969:Molecular Sequence Data; D011392:Proline / Q000235:genetics; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology*; D016415:Sequence Alignment; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D012698:Serologic Tests / Q000379:methods*; D017171:Strongyloides stercoralis / Q000235:genetics*; D013322:Strongyloidiasis / Q000175:diagnosis* / Q000276:immunology
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D018076:DNA, Complementary; D018509:DNA, Helminth; D007074:Immunoglobulin G; D011994:Recombinant Proteins; D007073:Immunoglobulin E; D011392:Proline