ANTIGENS OF ADULTS AND 3RD-STAGE LARVAE OF THE MENINGEAL WORM, PARELAPHOSTRONGYLUS-TENUIS (NEMATODA, METASTRONGYLOIDEA)

We studied the antigens of adults and third-stage larvae of the mening eal worm, Parelaphostrongylus tenuis, in an attempt to identify potent ial serodiagnostic molecules for this important infection of wild ungu lates. Soluble extracts of P. tenuis adult worms and third-stage larva e were separated by sodium dodecyl sulfate polyacrylamide gel electrop horesis (SDS-PAGE) and two-dimensional (2D) electrophoresis and analyz ed by immunoblotting using purified rabbit anti-P. tenuis immunoglobul in G (IgG). The IgG antibodies were obtained from animals immunized wi th P. tenuis adult worm or third-stage larva soluble extract and serum from elk infected with P. tenuis. Out of more than 75 antigens (as sh own by 2D electrophoresis and immunoblotting), 7 antigens from adults (four 170-120-kD molecules with isoelectric points between 6.0 and 6.6 , two 55-kD molecules with isoelectric points of 5.6 and 5.8, and one 13-kD molecule) and 2 antigens from third-stage larvae (one 25-30-kD m olecule with an isoelectric point of 6.3 and one 13-kD molecule) disti nguished P. tenuis from two other nematodes, Dictyocaulus viviparus an d Trichinella spiralis. Initial results using serum from experimentall y infected elk indicate that this serum recognized a similar profile o f P. tenuis antigens when compared with the serum from immunized rabbi ts. This research has set the foundation for the development of a test for P. tenuis infections in wild and recently domesticated elk and ot her ungulates.