RECOMBINANT CDNA CLONES FOR IMMUNODIAGNOSIS OF STRONGYLOIDIASIS

Because diagnosis of strongyloidiasis by stool examination is unreliab le and because of the potential for serious disease in Strongyloides i nfections, there is need for improved diagnostic aids to facilitate re cognition 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 r ecombinant proteins were equally or more reactive than the larval soma tic antigen, No cross-reactivity with recombinant antigen 5a was found with sera from patients with filarial or intestinal nematode infectio ns, 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.