Mycobacterium tuberculosis H37Rv infection regulates alternative splicing in Macrophages

Abstract

Objective: The objective of this study was to evaluate the expression of genes encoding SR proteinsand alternative splicing of IL4 and TLR4 in Mycobacterium tuberculosis (M. tb) H37Rv-infected macrophages. Materials and methods: THP-1 cells were induced to differentiate into macrophages with 200 nM PMA, and H37Rv strains were used for macrophage infection. After RNA extraction, qRT-PCR was performed to evaluate the expression of many SR proteins as well as the alternative splicing of IL4 and TLR4. Results: IL4 and TLR4 play significant roles in host immunity to tuberculosis. The level of IL-4 splice variants in THP-1 cells increased after M. tb H37Rv infection. Three splice variants of TLR4 were detected in M. tb-infected THP-1 cells, when compared with uninfected controls; the expression level of these splicing variants in M. tb-infected THP-1 cell was down-regulated. Since SR proteins are RNA-binding proteins that regulate RNA splicing, the expression of SR proteins was examined, and SRSF2 and SRSF3 were significantly down-regulated. In addition, splicing factors SRp75 and SF3a were also significantly down-regulated post M. tb infection. Conclusion: Our findings indicate that alternative splicing may be involved in host gene regulation post M. tb infection of macrophage cells.

Sp1 transcription factor represses transcription of phosphatase and tensin homolog to aggravate lung injury in mice with type 2 diabetes mellitus-pulmonary tuberculosis

“…Proinflammatory cytokines, including interleukins (IL)-12, IL-23, IL-18, and tumor necrosis factor-α (TNF-α) produced by infected macrophages and dendritic cells can induce the differentiation of Th1 cell and production of Th1 and Th1-like cytokines, such as interferon-γ (IFN-γ) and IL-2 which play critical roles in the expression of host resistance against mycobacterial infections [ 14 , 15 ]. By contrast, immunosuppressive cytokines such as IL-4, IL-10 and TGF-β produced by M2 macrophages are associated with immunodeficiency and the persistence and advanced infection with pathogens including MTB [ 15 , 41 ]. After successful treatment of PTB in infected patients, the type 2 inflammatory environment shifts back to type 1 [ 14 , 42 ].…”

Meta-analysis of active tuberculosis gene expression ascertains host directed drug targets

“…The disruption in the RNA splicing mechanism can lead to crosstalk in the intricate network interactions. The Mtb infection alters the patterns of alternate splicing within the macrophages by affecting the expression of SR proteins ( Zhang et al., 2018 ).…”

Transcriptome-Based Molecular Networks Uncovered Interplay Between Druggable Genes of CD8+ T Cells and Changes in Immune Cell Landscape in Patients With Pulmonary Tuberculosis

“…In order to verify our bioinformatics findings, we validated the expression of 9 druggable genes by the RT-PCR method. In brief, the RNA collected from THP-1 cell lines infected with the MTB strain (H37Rv) was collected after the post-incubation period as previously described (22). In brief, total RNA was reverse transcribed as complementary DNA (cDNA) and then amplified by the RT-PCR method using gene-specific oligonucleotide primers.…”