Evaluation of protective immune response in mice by vaccination the recombinant adenovirus for expressing Schistosoma japonicum inhibitor apoptosis protein

Parasitol Res. 2014 Nov;113(11):4261-9. doi: 10.1007/s00436-014-4104-5. Epub 2014 Sep 4.

Abstract

Schistosomiasis is a worldwide parasitic disease, and while it can be successfully treated with chemotherapy, this does not prevent reinfection with the parasite. Adenovirus vectors have been widely used for vaccine delivery, and a vaccination approach has the potential to prevent infection with Schistosoma. Here, we developed a recombinant adenoviral vector that expresses Schistosoma japonicum inhibitor apoptosis protein (Ad-SjIAP) and assessed its immunoprotective functions against schistosomiasis in mice. Murine immune responses following vaccination were investigated using enzyme-linked immunosorbent assays (ELISA), lymphocyte proliferation, and cytokine assays. The protective immunity in mice was evaluated by challenging with S. japonicum cercariae. Our results indicated that immunization with the Ad-SjIAP in mice induced a strong serum IgG response against IAP including IgG1, IgG2a, and IgG2b. In addition, lymphocyte proliferation experiments showed that mice treated with Ad-SjIAP significantly increased the lymphocyte response upon stimulation with recombinant Schistosoma japonicum inhibitor apoptosis protein (rSjIAP). Moreover, cytokine assays indicated that vaccination of Ad-SjIAP significantly increased the production of interferon (IFN)-γ and IL-2 as compared to the corresponding control group. Furthermore, following the challenge with S. japonicum cercariae, the vaccine conferred moderate protection, with an average rate of 37.95% for worm reduction and 31.7% for egg reduction. Taken together, our preliminarily results suggested that schistosoma IAP may be a potential vaccine against S. japonicum and that adenoviral vectors may serve as an alternative delivery vehicle for schistosome vaccine development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae
  • Animals
  • Antibodies, Helminth / blood
  • Enzyme-Linked Immunosorbent Assay
  • Helminth Proteins / immunology*
  • Immunoglobulin G / blood
  • Inhibitor of Apoptosis Proteins / immunology*
  • Interferon-gamma / immunology
  • Interleukin-2 / immunology
  • Lymphocyte Activation / immunology
  • Mice, Inbred BALB C
  • Parasite Egg Count
  • Schistosoma japonicum
  • Schistosomiasis japonica / immunology*
  • Spleen / cytology
  • Spleen / immunology
  • Vaccines, Synthetic / immunology*

Substances

  • Antibodies, Helminth
  • Helminth Proteins
  • Immunoglobulin G
  • Inhibitor of Apoptosis Proteins
  • Interleukin-2
  • Vaccines, Synthetic
  • Interferon-gamma