title: Protective immunity against toxoplasmosis in mice induced by single-dose immunization with rSAG1/2 protein released from poly(lactide-co-glycolide) microparticles.
abstract: Triphasic sustained release of tachyzoite chimeric protein, rSAG1/2, from poly(lactide-co-glycolide) (PLG)-encapsulated rSAG1/2 (PLG-rSAG1/2) microparticles (MPs) is a promising characteristic for developing a single-dose vaccine against Toxoplasma gondii in domestic animals. In the present study, we aimed to evaluate whether single immunization with PLG-rSAG1/2 MPs in BALB/c mice would achieve effective immunity and protection against T. gondii. Peritoneal immunization of mice with a single dose of PLG-rSAG1/2 MPs enhanced serum IgG titers and lymphocyte proliferation in a triphasic model over a long 12-week period. In addition, 12 weeks after immunization, significant production of IFN-γ was also monitored in mice vaccinated with one dose of PLG-rSAG1/2 MPs. More importantly, the immunity induced by one dose of PLG-rSAG1/2 MPs protected 70% of mice (14/20) against a lethal subcutaneous challenge of 1 × 104live tachyzoites of T. gondii (RH strain). In conclusion, a single dose of PLG-rSAG1/2 MPs capable of sustaining triphasic release of rSAG1/2 protein induces long-lasting triphasic immunity against T. gondii in mice. Our data indicate the feasibility of PLG-rSAG1/2 MPs to be developed as a single-dose vaccine against T. gondii for potential use in domestic animals.
authors.affiliation: Orthopaedic Research Center and Department of Physiology, College of Medicine, Kaohsiung Medical University, No. 100, Shih-Chuan 1st Road, Kaohsiung 807, Taiwan.
authors.forename: Shu-Chun
authors.initials: SC
authors.lastname: Chuang
authors.affiliation: Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, No. 1, Shuefu Road, Neipu, Pingtung 912, Taiwan.
authors.forename: Yao-Chi
authors.initials: YC
authors.lastname: Chung
authors.affiliation: Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, No. 1, Shuefu Road, Neipu, Pingtung 912, Taiwan.
authors.forename: Chung-Da
authors.initials: CD
authors.lastname: Yang
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000008:administration & dosage / Q000276:immunology*; D055252:Cell-Derived Microparticles / Q000737:chemistry / Q000276:immunology; D000939:Epitopes; D005260:Female; D007074:Immunoglobulin G / Q000097:blood; D007263:Infusions, Parenteral; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D019344:Lactic Acid / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D015800:Protozoan Proteins / Q000008:administration & dosage / Q000276:immunology*; D016052:Protozoan Vaccines / Q000008:administration & dosage; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000276:immunology; D013154:Spleen / Q000166:cytology / Q000276:immunology; D014122:Toxoplasma / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000276:immunology / Q000517:prevention & control*
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D000939:Epitopes; D007074:Immunoglobulin G; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D012333:RNA, Messenger; D011994:Recombinant Proteins; C047168:SAG1 antigen, Toxoplasma; C067547:surface antigen P22, Toxoplasma; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D007371:Interferon-gamma