Protective vaccination alters gene expression of the liver of Balb/c mice in response to early prepatent blood-stage malaria of Plasmodium chabaudi

Abstract

Current knowledge about liver responses to blood-stage malaria and their modulation by vaccination is still unclear. This study investigated effects of protective vaccination on liver gene and lincRNA expression of Balb/c mice at early prepatency of Plasmodium chabaudi blood-stage malaria. When a blood-stage vaccine was used to induce > 80% survival of otherwise lethal malaria, significant differences (p < 0.01) were detectable in global liver gene expression between vaccination-protected (potentially surviving) and non-protected non-vaccinated mice on day 1 p.i.. In the livers of protected mice, gene expression microarrays identified 224 and 419 genes, whose expression was up- and downregulated by > 3-fold, respectively. There were 24 genes upregulated by > 10-fold, including 10 IFN-inducible genes encompassing GTPases Irgm1, 2, and 3, and guanylate-binding protein Gbp11, the IL-1 decoy receptors Il1f9 and Il1ra1, the Il6 gene, and the gene for facilitated glucose transportation. Moreover, the IL-18 decoy receptor gene Il18bp, Gzmb, the genes Lif and Osmr encoding proteins of the IL-6 family, and the taurine transporter gene Slc6a6 were expressed > 3-fold in vaccinated mice. The genes Gbp10, 6, 4 were expressed by > 50% in vaccination-protected than in non-vaccinated mice. In addition, 43 lincRNA species were up- and 36 downregulated. Our data suggested novel regulatory elements of potential anti-malaria activity activated by protective vaccination in the liver, evidenced in response to early prepatent infections in vaccination-protected mice of otherwise lethal blood-stage malaria of P. chabaudi.

Keywords: Blood-stage malaria; Gene expression; Liver; Plasmodium chabaudi; Prepatent infections; Protective vaccination.