title: Vaccination with Bivalent DNA Vaccine of α1-Giardin and CWP2 Delivered by Attenuated Salmonella typhimurium Reduces Trophozoites and Cysts in the Feces of Mice Infected with Giardia lamblia.
abstract: BACKGROUND
  Giardia lamblia is one of the most common infectious protozoans in human that may cause diarrhea in travelers. Searching for antigens that induced effectively protective immunity has become a key point in the development of vaccine against giardiasis.
  
  
  RESULTS
  Mice vaccinated with G. lamblia trophozozite-specific α1-giardin DNA vaccine delivered orally by attenuated Salmonella typhimurium SL7027 elicited 74.2% trophozoite reduction, but only 28% reduction in cyst shedding compared with PBS buffer control. Oral vaccination with Salmonella-delivered cyst-specific CWP2 DNA produced 89% reduction in cysts shedding in feces of vaccinated mice. Significantly, the mice vaccinated with Salmonella-delivered bivalent α1-giardin and CWP2 DNA vaccines produced significant reduction in both trophozoite (79%) and cyst (93%) in feces of vaccinated mice. This parasite reduction is associated with the strong local mucosal IgA secretion and the IgG2a-dominant systemic immune responses in vaccinated mice.
  
  
  CONCLUSIONS
  The results demonstrate that bivalent vaccines targeting α1-giardin and CWP2 can protect mice against the colonization of Giardia trophozoite and block the transformation of cyst in host at the same time, and can be used to prevent Giardia infection and block the transmission of giardiasis.
authors.affiliation: The Department of Pathogenic Biology, Jilin Medical University, Jilin City, China.
authors.forename: Xian-Min
authors.initials: XM
authors.lastname: Feng
authors.affiliation: The Center Hospital of Jilin City, Jilin City, China.
authors.forename: Wen-Yu
authors.initials: WY
authors.lastname: Zheng
authors.affiliation: The Department of Pathogenic Biology, Jilin Medical University, Jilin City, China.
authors.forename: Hong-Mei
authors.initials: HM
authors.lastname: Zhang
authors.affiliation: The Department of Pathogenic Biology, Jilin Medical University, Jilin City, China.
authors.forename: Wen-Yan
authors.initials: WY
authors.lastname: Shi
authors.affiliation: The Department of Pathogenic Biology, Jilin Medical University, Jilin City, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Li
authors.affiliation: The Department of Pathogenic Biology, Jilin Medical University, Jilin City, China.
authors.forename: Bai-Ji
authors.initials: BJ
authors.lastname: Cui
authors.affiliation: The Department of Pathogenic Biology, Jilin Medical University, Jilin City, China.
authors.forename: Hui-Yan
authors.initials: HY
authors.lastname: Wang
mesh_terms: D000818:Animals; D000917:Antibody Formation / Q000276:immunology; D003598:Cytoskeletal Proteins / Q000276:immunology; D005243:Feces / Q000382:microbiology* / Q000469:parasitology; D005260:Female; D005455:Fluorescent Antibody Technique; D016829:Giardia lamblia / Q000276:immunology*; D005873:Giardiasis / Q000097:blood / Q000276:immunology* / Q000469:parasitology; D007109:Immunity; D007074:Immunoglobulin G / Q000276:immunology; D007413:Intestinal Mucosa / Q000469:parasitology / Q000473:pathology; D008198:Lymph Nodes / Q000473:pathology; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000378:metabolism; D015800:Protozoan Proteins / Q000276:immunology*; D012486:Salmonella typhimurium / Q000378:metabolism*; D053058:Trophozoites / Q000276:immunology*; D014611:Vaccination; D019444:Vaccines, DNA / Q000276:immunology*
chemical_list: D003598:Cytoskeletal Proteins; D007074:Immunoglobulin G; D015800:Protozoan Proteins; D019444:Vaccines, DNA; C038207:giardin protein, Giardia lamblia