Stage-specific antigens of Nematospiroides dubius.

The results presented here demonstrate conclusively for the first time that Nematospiroides dubius exhibits stage specificity in the expression of cuticular antigens, and infer that the stage specific antigens demonstrable on L4 stages 6 days following infection account for the immunity generated by abbreviated infection regimes. L4 stages 6 days following infection appeared to possess a stage-specific surface molecule (MW 16,000) which either disappeared on maturity to adults or somehow became unavailable to the surface probes used in this study. A molecule of similar molecular size was recognized by sera raised in mice immunized either by the administration of irradiated larvae or by using an antihelminthic-abbreviated infection and also by sera from jirds which had recently expelled N. dubius. The immune derivation of these sera supports the hypothesis that the molecule having a MW of 16,000 is functionally immunogenic. A monoclonal antibody (29-1-D1) was used to demonstrate a further stage specific molecule (MW 65,000), this time on the surface of adult N. dubius. The application of biochemical techniques suggested that further heterogeneity existed in surface molecules resolving between 60,000-70,000 on SDS-PAGE and a hypothesis was formulated in an attempt to explain this phenomenon.