Glycyrrhizinate dipotassium (DG) is a widely used anti-inflammatory, anti-microbial and anti-viral agent isolated from the licorice root. This study aims to investigate the potential antiviral activity of DG and its underlying mechanisms of protection against infectious bursal disease virus (IBDV) in vivo. The international guiding principles for Biomedical Research Involving Animals were followed during animal experiment. Measured the indices of immune organs including spleen, thymus and bursa of Fabricius, level of anti-IBDV antibody (Ab), IFN-γ and IFN-β in serum through ELISA, lymphocyte proliferation and the ratio of CD4⁺/CD8⁺ in blood using MTT and flow cytometry respectively and the expression of IBDV VP1 and TLR3 host gene in bursa of Fabricius were also evaluated by qRT-PCR. The DG treatment groups showed increased immunological index of spleen, thymus and bursa of Fabricius, a much higher ratio of CD4⁺/CD8⁺, the levels of anti-IBDV Ab, IFN-γ and IFN-β in serum were up-regulated varyingly, inhibit the VP1 expression and also up-regulated the TLR3 expression in bursa of Fabricius. These findings suggested that DG inhibited IBDV infection in vivo through multiple pathways and DG is a promising drug candidate for further development.

To Cite This Article: Sun N, Sun P, Xie N, Khan A, Sun Y, Fan K, Yin W and Li H, 2019. Antiviral and immunomodulatory effects of dipotassium glycyrrhizinate in chicks artificially infected with infectious bursal disease virus. Pak Vet J, 39(1): 43-48. http://dx.doi.org/10.29261/pakvetj/2018.109