title: Mice intranasally immunized with a recombinant 16-kilodalton antigen from roundworm Ascaris parasites are protected against larval migration of Ascaris suum.
abstract: Protective immunity to the pig roundworm, Ascaris suum, has been demonstrated by immunization of pigs with antigens derived from the parasite's larval stages. We identified a protective antigen commonly expressed in the human and pig Ascaris infections as a 16-kDa protein (As16), which has no similarity at the amino acid level to mammalian proteins but has some similarity to those of the filarial parasites and Caenorhabditis elegans gene product. Localization analysis revealed that the native As16 was highly expressed in the adult worm intestine, hypodermis, and cuticles. In addition, As16 was detected in the parasite excretory and secretory products. Mice intranasally vaccinated with Escherichia coli-expressed recombinant As16 (rAs16), coupled with cholera toxin B subunit, generated a significant increase in the level of rAs16-specific immunoglobulin G (IgG) and IgE in serum. Mucosal IgA levels were also increased. The recombinant protein evoked a mixed (both Th1 and Th2) type of immune response characterized by elevated levels of gamma interferon and interleukin-10 in the culture supernatants of activated spleen cells. An increased level of IgG1 and IgG2a in serum was also observed. The vaccinated mice showed a reduction by 58% in the recovery of challenged larvae compared to a nonvaccinated control. These results suggest the possibility of developing a mucosal vaccine for human and pig ascariasis.
authors.affiliation: Laboratory of Parasitic Diseases, National Institute of Animal Health, National Agricultural Research Organization, Tsukuba, Ibaraki 305-0856, Japan. tsujin@affrc.go.jp
authors.forename: Naotoshi
authors.initials: N
authors.lastname: Tsuji
authors.forename: Kayo
authors.initials: K
authors.lastname: Suzuki
authors.forename: Harue
authors.initials: H
authors.lastname: Kasuga-Aoki
authors.forename: Takashi
authors.initials: T
authors.lastname: Isobe
authors.forename: Takeshi
authors.initials: T
authors.lastname: Arakawa
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Matsumoto
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000281:Administration, Intranasal; D000595:Amino Acid Sequence; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000947:Antigens, Helminth / Q000008:administration & dosage* / Q000737:chemistry / Q000235:genetics; D001196:Ascariasis / Q000276:immunology* / Q000469:parasitology / Q000517:prevention & control*; D017165:Ascaris suum / Q000235:genetics / Q000276:immunology* / Q000502:physiology; D001483:Base Sequence; D002772:Cholera Toxin / Q000008:administration & dosage; D016207:Cytokines / Q000096:biosynthesis; D018076:DNA, Complementary / Q000235:genetics; D018509:DNA, Helminth / Q000235:genetics; D005260:Female; D015801:Helminth Proteins / Q000008:administration & dosage* / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D034421:Sus scrofa; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics
chemical_list: D000276:Adjuvants, Immunologic; D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D016207:Cytokines; D018076:DNA, Complementary; D018509:DNA, Helminth; D015801:Helminth Proteins; D011993:Recombinant Fusion Proteins; D014614:Vaccines, Synthetic; D002772:Cholera Toxin