Trichinella spiralis: immunocytochemical localization of surface and intracellular antigens using monoclonal antibody probes

Abstract

A panel of immunologically and biochemically defined monoclonal antibody probes has been used in conjunction with immunocytochemical techniques to localize target antigens in sections of different life-cycle stages of Trichinella spiralis. Monoclonals that immunoprecipitate surface components from adult worms, show reactivity with the surface but not with internal tissues of sectioned parasites. Reagents that immunoprecipitate radio-isotope labelled stage-specific surface components of muscle-stage larvae, however, react with the stichosome and gut lining of sectioned larvae, as well as with the surface. Monoclonal antibody probes that do not stain the surfaces of live, intact muscle larvae in immunofluorescence assays, but which immunoprecipitate solubilized surface glycoproteins, also show reactivity with cuticular and stichosomal antigens of sectioned larvae. The more powerful resolution provided by electron microscopy has localized the surface antigens to the epicuticle and the intestinal antigens to the brush-border microvilli. Of particular interest was the finding that antigens of muscle-stage larvae, known to confer protection upon recipient mice, also exist in the stichosome of adult parasites. This observation may shed some light on the fact that mice immunized with antigens from muscle-stage larvae show, in addition to reduced muscle larva burden, accelerated expulsion of adult worms. The implications of these data for stage specificity of immune responses to trichinosis are discussed.

Preparation and characterization of monoclonal antibodies against ES antigens of Trichinella spiralis

“…The immunofluorescent location showed that the nine MAbs generated in this study reacted with the surface of the whole larvae isolated at 40 dpi and the surface as well as internal tissues of sectioned parasites at 20 dpi and 40 dpi, indicating their epitopes were localized at the surface and internal tissues of the larvae. The results are similar to those obtained by McLaren et al (1987). However, because the ES antigens of T. spiralis muscle larvae have many immunodominant epitopes, most of the MAbs against ES antigens can recognize more than one protein band (Zhu & Bell, 1990;Romarís et al, 2001;Zumaquero-Ríos et al, 2012).…”

Workshop on a detailed characterization of Trichinella spiralis antigens: a platform for future studies on antigens and antibodies to this parasite

“…Among them, TSL-1 antigens have been the most extensively characterized both biochemically and immunologically. These antigens are stage specific, originate in the ML stichosome, and are abundant in both E/S products and on the larval cuticular surface (McLaren, Ortega-Pierres & Parkhouse 1987). The family of TSL-1 antigens migrate under reducing conditions on SDS-PAGE in a molecular weight range of 40-70 kDa, and resolve into at least six different protein bands.…”

Evidence that a 16-kilodalton integral membrane protein antigen from Schistosoma japonicum adult worms is a type A2 phospholipase

“…Sections (1 VLm) attached to glass slides were incubated with antibody to bee venom PLA2 or normal serum, washed with PBS, and then incubated with a fluorescein-labeled second antibody as described elsewhere (14). Washed sections were mounted under glass coverslips and examined with a Zeiss microscope by using epifluorescence.…”