The use of a synthetic antigen for the serological diagnosis of human trichinellosis

Hosts infected with Trichinella produce antibodies specific for an epitope common to the TSL-1 family antigens. This epitope contained uncommon termin al 3, 6-dideoxy-D-arabinohexose (so called tyvelose) residues. The disaccha ride moiety was synthesized and an immunodiagnostic assay was developed, wh ich was specific and sensitive in swine trichinellosis. We aimed to verify the specificity and sensitivity of this immunodiagnostic test in human tric hinellosis. 15 sera from normal subjects, 12 from patients with other paras itic diseases and 50 from trichinellosis patients were tested. Indirect enz yme linked immunosorbent assay (ELISA) for specific IgG and an amplified EL ISA for specific IgE were performed using beta -tyvelose-GalNAc-bovine seru m albumin (BSA) disaccharide conjugate or T. spiralis muscle larvae excreto ry/secretory (E/S) products, as antigens. Neither control sera nor other pa rasitic infection sera resulted positive both for IgG and IgE when syntheti c or E/S antigens were used. In trichinellosis patient sera, specific IgG w ere present in 100 % of cases, irrespective of the antigen used, but wherea s specific IgE were detected in 78 % using E/S antigens, a 100% positivity rate was obtained, using the beta -tyvelose- BSA conjugate.