Evaluation of interferon gamma (IFN-γ) of Labeo rohita as an immunomodulator: in vitro expression model
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Interferon gamma (IFN-γ) or type II interferon is a cytokine that is critical for innate and adaptive immunity against viral and some bacterial and protozoal infections. The importance of IFN-γ in the immune system lies in its ability to inhibit viral replication directly and most importantly from its immunomodulatory effects. Previously, we successfully co-administered IFN-γ along with GAPDH gene of Edwardsiella tarda as bicistronic DNA vaccine in Labeo rohita. In order to ascertain the individual role of IFN-γ, the present study involves cloning and expression of 552-bp IFN-γ open-reading frame (ORF) of L. rohita in striped snakehead (SSN-1) cell line using eukaryotic expression vector system (pQE-TriSystem) followed by transfection in peripheral blood lymphocytes (PBMCs) to evaluate its immunomodulatory ability in comparison to polyinosinic-polycytidylic acid (Poly I:C)-treated PBMCs. The 18.7-kDa protein, expressed in the pQE-IFNγ-transfected SSN-1 cells, reacted with anti-His antibody in Western blot confirming it to be recombinant IFN-γ, whereas the relative expression of IFN-γ, iNOS, Mx, and IL-1β genes in PBMCs was quantified at 24 h and 48 h post treatment by qPCR. The comparative kinetics of all four genes showed significantly (p < 0.05) high upregulation pattern in both pQE-IFNγ-transfected cell group and Poly I:C-treated cell group demonstrating recombinant IFN-γ as an equally efficient inducer like Poly I:C. Thus, our in vitro experiment results highlight the immunomodulatory potential of recombinant IFN-γ as an analogue to synthetic Poly I:C which warranted future studies to further explore the potential of recombinant IFN-γ as an effective vaccine adjuvant against different microbial invasion.
KeywordsIFN-γ Labeo rohita Peripheral blood mononuclear cells Poly I:C
The authors thank the present Director Dr. Gopal Krishna and Ex-Director Dr. W S Lakra, ICAR-Central Institute of Fisheries Education, Mumbai, India, for providing necessary facilities and support for this study.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Du Y, Qi J, Lu Y, Wu J, Yoo D, Liu X, Zhang X, Li J, Sun W, Cong X, Shi J, Wang J (2012) Evaluation of a DNA vaccine candidate co-expressing GP3 and GP5 of porcine reproductive and respiratory syndrome virus (PRRSV) with interferon α/γ in immediate and long-lasting protection against HP-PRRSV challenge. Virus Genes 45(3):474–487CrossRefGoogle Scholar
- Kole S, Kumari R, Anand D, Kumar S, Sharma R, Tripathi G, Makesh M, Rajendran KV, Bedekar MK (2018) Nanoconjugation of bicistronic DNA vaccine against Edwardsiella tarda using chitosan nanoparticles: evaluation of its protective efficacy and immune modulatory effects in Labeo rohita vaccinated by different delivery routes. Vaccine 36:2155–2165CrossRefGoogle Scholar
- Kumari R, Kole S, Soman P, Rathore G, Tripathi G, Makesh M, Rajendran KV, Bedekar MK (2018) Bicistronic DNA vaccine against Edwardsiella tarda infection in Labeo rohita: construction and comparative evaluation of its protective efficacy against monocistronic DNA vaccine. Aquaculture 485(C):201–209CrossRefGoogle Scholar
- Secombes CJ (1996) The nonspecific immune system: cellular defences. In: The fish immune system: organism, pathogen, and environment. Vol 15. Academic PressGoogle Scholar
- Zhou Z, Hamming OJ, Ank N, Paludan SR, Nielsen AL, Hartman R (2007) Type III interferon (IFN) induces type I IFN-like response in the restricted subset of cell through signaling pathways involving both the jak- STAT pathway and nitrogen activated protein kinases. J Virol 81:7749–7758CrossRefGoogle Scholar