Immune response toTrichinellaepitopes: the antiphosphorylcholine plaque-forming cell response during the biological cycle

Abstract

Phosphorylcholine (PC), an immunodominant component of the cell wall of certain bacteria, fungi and nematodes, is known to induce low anti-PC antibody levels during natural infection by Trichinella spiralis. This article reports a study in which spleen cells from BCF1 mice infected with Trichinella sp. larvae were found to produce large numbers of direct haemolytic plaques in response to PC conjugated to sheep red blood cells (SRBC) after muscle-encysted larvae had been killed by treatment with mebendazole. Inhibition of the response by PC-chloride, immunodiffusion and immunoelectrophoretic studies with the anti-PC IgA (TEPC-15) and anti-idiotype T15 serum assays showed the plaque-forming cell (PFC) response to be specific for PC. The absence of haemolytic plaques when unconjugated SRBC or TNP-SRBC were used as indicator cells ruled out involvement of a polyclonal response. Greatest anti-PC PFC response was found to be associated with a microsomal fraction designated FCp1, a particulate fraction behaving as a thymus-dependent antigen. The FCp1 fractions from all four strains of Trichinella employed induced anti-PC PFC responses when injected into mice. These results suggest that FCp1 is a suitable antigen for use in detailed studies of immune responses to Trichinella and related parasites.

Allergenic Cross-Reactivity of Several Strains of <i>Trichinella</i> in Mice and Rats by the Passive Cutaneous Anaphylaxis Technique

“…The cytosolic fraction FCs of Trichinella was ob tained from muscular LI larvae of the parasite as pre viously described [6], with minor modifications. Briefly, the larvae suspended in phosphate-buffered saline were homogenized in a tissue grinder homogenizer and then treated with ultrasound for 30 min.…”

Genetic control of the immune response to Trichinella spiralis: recognition of muscle larval antigens

“…Certainly there are several dissimilar epitopes upon each major antigen, which in itself is interesting because this shows that not all of these can consist of just one commonly occurring molecule e.g. phosphorylcholine (which is known to be antigenic upon many parasitic nematodes, including T. spiralis) (Pery et al 1974, Maizels et al 1987, Ubeira et al 1987. The probability that one or more of the epitopes could be a carbohydrate moiety has been shown by recent work by Denkers et al (1990), using MoAb 130.…”

Characterization of two monoclonal antibodies raised in Btkxid mice that recognize phosphorylcholine‐bearing antigens from Trichinella and other helminths

“…A Trichinella spiralis strain, typed as GM‐1 in the World Health Organization classification and as ISS48 (T1a) in that of Pozio et al . (16), was maintained in CD1 mice, and larvae were obtained by HCl/pepsin digestion as described previously (17). The cestode Bothriocephalus scorpii was obtained from the intestine of turbots ( Scophthalmus maximus ) caught off the north‐west coast of Spain.…”