title: The extracellular matrix protein mindin as a novel adjuvant elicits stronger immune responses for rBAG1, rSRS4 and rSRS9 antigens of Toxoplasma gondii in BALB/c mice.
abstract: BACKGROUND
  Vaccines are the most effective agents to control infections. However, recombinant vaccines often do not elicit strong immune responses. Protein antigens combined with proper adjuvants have been widely used to induce immune responses, especially the humoral immune responses, against various pathogens, including parasites. The extracellular matrix protein mindin has been recognised as an immune facilitator for initiating innate immune responses. It has therefore been expected to be a potentially potent adjuvant in the development of novel vaccines. The aim of this study was to investigate whether mindin could facilitate the induction of antigen-specific immune responses to recombinant antigens (rBAG1, rSRS4 and rSRS9) of Toxoplasma gondii in BALB/c mice.
  
  
  METHODS
  In this study, we explored the adjuvant effect of the recombinant mindin in the generation of specific Th1 and Th2 responses to each of three T. gondii antigens, BAG1, SRS4 and SRS9. All mice in the experimental groups received either antigen alone or in combination with Freund's adjuvant or with the recombinant mindin. The immune responses after immunisation were measured by ELISA and lymphoproliferative assays. The immunised mice were challenged with live T. gondii tachyzoites, and the protection efficiency was compared between the groups.
  
  
  RESULTS
  Our results revealed that mindin as an adjuvant could facilitate the recombinant proteins to efficiently stimulate humoral and cellular responses, including antigen-specific IgG1 and IgG2a, as well as lymphocyte proliferation. Furthermore, significantly improved protection against T. gondii infection was observed in the mindin group compared with that of Freund's adjuvant and no-adjuvant groups.
  
  
  CONCLUSIONS
  The extracellular matrix protein mindin can effectively induce antigen-specific humoral and cell-mediated immune responses. Our study provides a valuable basis for the development of an efficient, safe, non-toxic vaccine adjuvant for future use in humans and animals.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Sun
authors.forename: Mei
authors.initials: M
authors.lastname: Mei
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.forename: Fusong
authors.initials: F
authors.lastname: Han
authors.forename: Boyin
authors.initials: B
authors.lastname: Jia
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Wei
authors.forename: Zhiguang
authors.initials: Z
authors.lastname: Chang
authors.forename: Huijun
authors.initials: H
authors.lastname: Lu
authors.forename: Jigang
authors.initials: J
authors.lastname: Yin
authors.affiliation: Key Laboratory of Zoonosis, College of Veterinary Medicine, Jilin University, Xi An Da Lu 5333, Changchun 5333, China. cqj@jlu.edu.cn.
authors.forename: Qijun
authors.initials: Q
authors.lastname: Chen
authors.forename: Ning
authors.initials: N
authors.lastname: Jiang
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000235:genetics; D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology; D000953:Antigens, Protozoan / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D016326:Extracellular Matrix Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D007114:Immunization; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D015800:Protozoan Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D016052:Protozoan Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D014122:Toxoplasma / Q000235:genetics / Q000276:immunology*; D014123:Toxoplasmosis / Q000276:immunology* / Q000469:parasitology / Q000517:prevention & control; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016326:Extracellular Matrix Proteins; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D014614:Vaccines, Synthetic; C121491:mindin
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