Immunoblot analysis of antibodies in human strongyloidiasis.

An electrophoretic transfer technique was used to investigate qualitatively the production of antibodies to Strongyloides stercoralis larvae in 56 patients with strongyloidiasis. SDS-PAGE analysis of the larval extract revealed the presence of at least 33-39 polypeptide bands under either reducing or non-reducing condition. In the immunoblot analysis, almost all patients showed positive reactivity to the polypeptide bands. The reactivity, however, revealed significant variation among the patients, ranging in number of bands from only one to more than 18. Among the bands, 4 with molecular sizes of 97, 66, 41 and 26 kDa were frequently recognized by the patients' sera, indicating that these antigenic components may form an available antigen for immunological testing for strongyloidiasis. On the other hand, the reactivities were very faint in cases of overwhelming strongyloidiasis.