Trichinella spiralis: ultrastructural localization of a target antigen recognized by a monoclonal antibody

The localization of a 160-kDa molecule recognized by a monoclonal antibody of the IgG1-class (TS32D12) to Trichinella spirilis was demonstrated at the subcellular level. Mature muscle larvae recovered from infected mice were fixed with Zamboni solution, and embedded in LR white resin. Ultrathin sections were incubated with TS32D12 and subsequently stained using a secondary antibody-coated colloidal gold probe. TS32D12 reacted to constituents in the alpha-stichosome cells of the parasite; that is, alpha-granules and rough endoplasmic reticulum. Other structures were not recognized by the immunogold probe, but occasionally weak positive staining was seen on beta-granules, the cuticle, hypodermis and myofibrils.