RNA-seq analysis of the mouse brain reveals inflammatory genes associated with early artesunate treatment of experimental cerebral malaria
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ABSTRACT: Purpose:This study aimed to investigate the transcriptome-wide response of experimental cerebral malaria (ECM) and artesunate treated mice brain on 6 days post-infection. Methods: C57BL/6 mice were infected with Plasmodium berghei ANKA to construct a murine ECM in MB and AB group. AB group treated with artesunate (30mg/kg), while CB group treated with PBS for 4 days. Mice brain was tested by RNA-seq. Results: Gene ontology and KEGG pathway analyses of differentially expressed genes (DEGs) were performed. quantitative reverse transcription polymerase chain reaction (qPCR) verify DEGs such as Il6, Il1b, Il10, Tnf, Ifng, Il21, Icam1, which were up-regulated in MB vs. CB, while down-regulated in AB vs. MB. Conclusions:Our study revealed a transcriptome-wide profile in ECM and artesunate treated mice brain, and help to explore the underlying mechanism, as well as the further development of therapeutic strategies for clinical cerebral malaria.
Project description:Cerebral malaria is a pathology involving inflammation in the brain. There are many immune cell types activated during this process, but there is little information on the contribution of microglia, the brain resident macrophages, to this severe complication. We have examined the responses of microglia in a model of experimental cerebral malaria (ECM), in which C57BL/6 mice are infected with Plasmodium berghei ANKA. Genome wide transcriptomic analysis of these cells revealed that thousands of transcripts were differentially expressed at two different time points during the infection. The analysis indicated that proliferation of microglia was a dominant feature before the onset of ECM, and supporting this, we observed an increase in numbers of these cells in the brain. When cerebral malaria symptoms were manifest, genes involved in immune responses and chemokine production were upregulated, which were possibly driven by Type I Interferon. Together, our data offer a unique insight into the responses of microglia in the brain during ECM.
Project description:Whole gene methylation profiles of U87 and U251 glioma cells before and after artesunate treatment, Infinium MethylationEPIC BeadChip, samples including 3 U87 cell normal group, 3 U251 cell normal group, 3 artesunate treated U87 cell group, U251 cell group was treated with 3 artesunate.
Project description:Cerebral malaria (CM) is one of the most severe complications of malaria infection. There is evidence that repeated parasite exposure promotes resistance against CM, as indicated by the low incidence of CM in adults in malaria-endemic regions. However, the immunological basis of this infection-induced resistance remains poorly understood. Here, a microarray study done utilising the tractable Plasmodium berghei ANKA model of experimental cerebral malaria (ECM), we show that three rounds of infection and drug-cure protects against the development of ECM during a subsequent fourth infection.
Project description:Cerebral Malaria (HCM) is a serious neurological complication caused by Plasmodium falciparum infection. Currently the only treatment for HCM is the provision of anti-malarial drugs; however, such treatment by itself often fails to prevent death or development of neurological sequelae. To identify new potential adjunct treatments for HCM, we performed a non-biased whole brain transcriptomic time-course analysis of anti-malarial drug chemotherapy of murine experimental CM (ECM).
Project description:Infection of C57BL/6 mice with Plasmodium berghei ANKA (PbA) is a well-established experimental model of cerebral malaria (ECM). ECM is characterised by high levels of parasite sequestration and recruitment of pathogenic CD8+ T cells to the brain. The role of CD4+ T cells in this model has not yet been fully elucidated, although our laboratory has recently shown that CD4+ T cell depletion prior to infection results in significantly lower parasite burdens and protection from ECM. These data highlight a pathogenic role for CD4+ T cells in ECM. Our unpublished observations indicate that mice lacking the CD8+ T cell cytolytic effector molecule, Granzyme B, (GzmB), are resistant to ECM, showing markedly reduced parasite burdens. Late depletion of CD4+ T cells from PbA-infected GzmB-deficient mice results in enhanced parasite burdens, indicating that these cells may play an anti-parasitic role. In the present study, we have analysed splenic CD4+ T cell gene expression profiles in naïve C57BL/6 mice, and PbA-infected wild-type and GzmB-deficent mice to further our understanding of the CD4+ T cell response in ECM. Splenic CD4 T cells isolated by cell sorting from either uninfected C57BL/6 or PbA-infected C57BL/6 or B6.GzmB-/- mice at day 4 post-infection. Total RNA obtained from four mice per group.
Project description:Cerebral malaria is the most deadly manifestation of infection with Plasmodium falciparum. The pathology of cerebral malaria is characterised by the accumulation of infected erythrocytes in the microvasculature of the brain, due to parasite adhesins on the surface of infected erythrocytes binding to human receptors on microvascular endothelial cells. The parasite and host molecules involved in this interaction are unknown. We used the Human Brain Endothelial Cell line HBEC-5i to identify the malaria parasite ligands responsible for binding to human brain endothelial cells. Three P. falciparum strains (HB3, 3D7 and IT/FCR3) were selected for binding to HBEC5i and the whole transcriptome of selected and unselected parasites was analysed using a variant surface antigen-supplemented microarray chip. After selection, the only highly upregulated genes were a subset of group A-like var genes (HB3var3, 3D7_PFD0020c, ITvar7 and ITvar19), that showed 11 to >100-fold higher transcription levels in selected parasites. These genes are highly diverse in sequence, but do however show strong similarities in PfEMP1 architecture. Antibodies raised to the HB3var3 variant recognized the surface of infected erythrocytes and abolished the binding of infected erythrocytes to brain endothelial cells. The subset of Group A PfEMP1 variants identified here provides a new target for interventions to treat or prevent cerebral malaria.
Project description:In malaria, T cells play a dual role by both restricting parasite growth and mediating immunopathology such as the deadly neuroinflammation called cerebral malaria. During experimental cerebral malaria (ECM), IFN produced by CD4 T cells promotes CD8 T cell sequestration in brain capillaries, resulting in endothelial damage, oedema and death. However the antigen-presenting cells controlling the development of CD4 T cell responses, as well as the antigens recognized by these CD4 T cells, are unknown. Here we used mass spectrometry to characterize the MHC II immunopeptidome presented by dendritic cells during blood stage malaria in C57BL/6 mice. We identified 14 MHC II ligands derived from 13 conserved Plasmodium berghei proteins that we validated in vivo. This work profiles the first MHC II immunopeptidome in a mouse model of blood stage malaria.
Project description:Gene expression patterns were investigated in well-defined genetically cerebral malaria-resistant (CM-R) and cerebral malaria-susceptible (CM-S) mouse strains. cDNA microarrays were used to search for differentially expressed genes in mouse brain. Four mouse strains, known to differ in susceptibility to cerebral malaria upon Plasmodium berghei ANKA infection, were compared: BALB/c and DBA/2 mice are CM-R, while C57BL/6 and CBA/J mice are CM-S.
Project description:Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection, predominantly experienced by children and non-immune adults, which results in great mortality and long-term sequelae. Recent reports based on histology of post-mortem brain tissue suggest that CM may be the common end point for a range of syndromes. Here, we have analysed the gene expression profiles in brain tissue taken from experimental CM (ECM)-susceptible, Plasmodium berghei ANKA (PbA)-infected C57BL/6 (B6) and CBA/CaH (CBA) mice with ECM. Gene expression profiles were largely heterogeneous between the two ECM-susceptible strains. These results, combined with experimental data, support the existence of distinct pathogenic pathways in CM. Keywords: disease state analysis