Translation products of mRNA from infective larvae of Trichinella spiralis include an antigenic polypeptide.
Total RNA was extracted from packed infective larvae of Trichinella spiralis by centrifugation through a 5.7 M caesium chloride cushion. Polyadenylated messenger RNA was separated from total RNA in an oligothymidylic acid-cellulose gel column. The in vitro translation of the mRNA, isolated from infective larvae of T. spiralis, was carried out using the rabbit reticulocyte cell-free translation system. Incorporation of 35S-methionine into the trichloroacetic acid precipitates in the lysate containing mRNA was 5 times greater than that in control. The translation products were analysed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) followed by autoradiography. Many polypeptides with molecular weights of less than 100,000 were synthesized in the lysate. A T. spiralis positive mouse serum was mixed with translation products to form antigen-antibody complexes, which were then absorbed by Staphylococcus aureus Cowan 1 strain and analysed by autoradiography of SDS-PAGE. An antigenic polypeptide with a molecular weight of 48,000 was demonstrated to react specifically with IgG antibody in T. spiralis positive mouse serum. T. spiralis larvae were cultured in methionine-free medium containing 35S-methionine, and antigenic polypeptides in somatic extracts and ES products were compared with those in translation products by autoradiography of SDS-PAGE. Several polypeptides in ES products and somatic extracts reacted specifically with IgG antibodies in positive serum. Especially the polypeptide with a molecular weight of 48,000 in ES products strongly reacted with IgG antibody in positive serum.
D000818:Animals; D000947:Antigens, Helminth / Q000032:analysis* / Q000235:genetics; D001345:Autoradiography; D004591:Electrophoresis, Polyacrylamide Gel; D007074:Immunoglobulin G / Q000276:immunology; D007814:Larva / Q000235:genetics / Q000276:immunology; D008297:Male; D051379:Mice; D010455:Peptides / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics*; D014234:Trichinella / Q000235:genetics* / Q000276:immunology
D000947:Antigens, Helminth; D007074:Immunoglobulin G; D010455:Peptides; D012333:RNA, Messenger