Dynamics of the IgG3 responses following immunisation of BALB/c mice with somatic and excretory/secretory antigens from various Trichinella species

Comparison of the dynamics and antigen recognition profiles of IgC3 followi ng immunisation with larval crude extracts (LCE) and excretory-secretory (E S) products from muscle larvae of different species of Trichinella (T. spir alis, T. nativa, T. britovi, T. nelsoni and genotype T6) was made in BALB/c mice. High levels of IgG3 response were obtained in ELISA following immuni sation with LCE from all species with maximum levels achieved between days 59 and 64 post-immunisation (p.i,) and maintained up to the limit of the ob servation (day 164). Antigen recognition profiles as measured by western-bl ot showed dense and numerous bands in the range 45-64 kDa that were consist ent from week 5(th) with variation in epitope recognition among the differe nt species. Following immunisation with ES antigens a significant decrease in IgG3 response was observed for all species especially for T. nativa in c omparison to LCE. Antigen recognition an ES antigens showed three main band s in the range of 45-60 kDa for all species excepting T. nelsoni and T. bri tovi where an additional band was also present. These results clearly show that IgG3 epitopes are more abundant in somatic (LCE) than in ES products o f Trichinella muscle larvae and that quantitative as well as qualitative va riations exist among different species.