Studies on the biochemical characteristics of Trichinella spiralis antigen and the immune method of swine trichinellosis

1. Biochemical characteristics of Trichinella spiralis antigens: four kinds of Trichinella spiralis antigens were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), isoelectric focusing (1EF), two-dimensional electrophoresis and immunoblotting (EITB) for the first time. The analysis showed that the soluble antigen of muscle larva contained at least glycoprotein, lipoprotein, glycolipid protein, simple protein, polysaccharide and esterase isozyme. Two-dimensional electrophoresis showed that there were 122 polypeptide spots, most of which were acidic peptides with molecular weight lower than 67KD.

The excretory-secretory (Es) antigen of muscle larvae contains at least glycoprotein, lipoprotein, glycolipid, pure protein and polysaccharide. Two-dimensional electrophoresis showed 61 polypeptide spots, most of which were acidic peptides with molecular weight lower than 67KD. The soluble antigens of adults and newborn larvae showed 26 and 11 protein bands respectively after SDS-PAGE.

two。 Study on immune methods of porcine trichinellosis: studies have shown that 7 antigens have good immune protective effects on mice and pigs. Among them, the immunogenicity of adult soluble antigen and inactivated newborn larva was the best, which could be induced to produce 95% in mice. Immunity (worm reduction rate) of 6% and 91.38%; immunity of 98.21% and 95.3% in pigs; and protection rates of 75.26% and 75.99% in regional trials, respectively.

The study of immune mechanism shows that the immunity induced by pig immunization with antigen not only reduces the number of worms, but also weakens the infectivity. Immune serum can kill muscle larvae in vitro. After immunization, the serum antibody increased, the number of B lymphocytes in peripheral blood decreased and the total number of T lymphocytes increased, in which the number of suppressor T cells increased, showing a temporary phenomenon of cellular immunosuppression. The immune duration was at least 6 months.

The soluble antigens of 7-day-old adults were emulsified with Baiyou Yiban adjuvant and immunized by intraperitoneal injection. Adult soluble antigen vaccine and inactivated newborn larva vaccine were preliminarily developed. With regard to the research results on the biochemical characteristics of Trichinella spiralis antigen and the immune methods of porcine trichinellosis, some biochemical characteristics of the four antigens were clarified, the immune characteristics of the antigens were clarified, and the effective immunogens and immune methods of porcine trichinosis were screened. Two kinds of vaccines with good protective effect on pigs have been developed. This achievement fills the domestic gap, reaches the domestic leading level and the international advanced level, and is of great academic significance and great potential application prospects.