Project description:In view of emerging drug-resistant tuberculosis, host directed therapies are urgently needed to improve treatment outcomes with currently available anti-tuberculosis therapies. One option is to interfere with the formation of lipid-laden “foamy” macrophages in the infected host. Here, we provide evidence that WNT6, a member of the evolutionary conserved WNT signaling pathway, promotes foam cell formation by regulating key lipid metabolic genes including acetyl-CoA carboxylase-2 (ACC2) during pulmonary TB. In addition, we demonstrate that Mycobacterium tuberculosis (Mtb) facilitates its intracellular growth and dissemination in the host by exploiting the WNT6-ACC2 pathway. Using genetic and pharmacological approaches, we show that lack of functional WNT6 or ACC2 significantly reduces intracellular TAG levels, Mtb growth and necrotic cell death of macrophages. In combination with the anti-TB drug isoniazid, pharmacological inhibition of ACC2 improved anti-mycobacterial treatment in vitro and in vivo. Therefore, we propose the WNT6-ACC2 signaling pathway as a promising target for a host-directed therapy to reduce intracellular replication of Mtb by modulating neutral lipid metabolism.
Project description:Investigation of whole genome gene expression level changes in BMDM adhered for 4 or 18hrs to Lab Tek Chamber slides pre-coated with 4ug/ml of human serum albumin (HSA) (control protein) or purified human C1q and treated with lipopolysaccharide (LPS: 20ng/ml) Mycobacterium avium 101 (M avium) or apoptotic Jurkat T cells. BMDM were obtained from C57Bl/6 and generated as previously described in Bohlson, SS, Strasser, JA, Bower JJ, Schorey J S 2001 Role of complement in Mycobacterium avium pathogenesis: in vivo and in vitro analyses of the host response to infection in the absence of complement component C3 Infec Immun 69: 7729-7735. Mybacterium avium 101 was obtained from Dr Jeff Schorey (University of Notre Dame). The human Jurkat T cell line was obtained from ATCC (Manassas, VA) and induced to undergo apoptosis with dexamethasone as described in Lillis, AP, Greenlee, M C, Mikhailenko I, Pizzo, S V, Tenner, A J, Strickland, D K, Bohlson, S S 2008 Murine Low-Density Lipoprotein Receptor-Related Protein 1 (LRP) Is Required for Phagocytosis of Targets Bearing LRP Ligands but Is Not Required for C1q-triggered Enhancement of Phagocytosis J Immunol 181: 364: 373. A six chip study using total RNA from 5 separate cultures of BMDM adhered to HSA for 4 hrs, 5 separate cultures of BMDM adhered to C1q for 4 hrs, 5 separate cultures of BMDM adhered to HSA for 4 hrs and infected with M avium at a 1:500 ratio of BMDM to M avium, 5 separate cultures of BMDM adhered to C1q for 4hrs and infected with M avium at a 1:500 ratio ofBMDM to M avium, 5 separate cultures of BMDM adhered to HSA for 4 hrs and infected with M avium at a 1:1000 ratio of BMDM to M avium, 5 separate cultures of BMDM adhered to HSA for 4 hrs and treated with 20ng/ml LPS, 5 separate cultures of BMDM adhered to C1q for 4 hrs and treated with 20ng/ml LPS, 5 separate cultures of BMDM adhered to HSA for 4 hrs and treated with 20ng/ml LPS and co-cultured with apoptotic Jurkat cells at a 1:3 ratio of BMDM to apoptotic cells, 5 separate cultures of BMDM adhered to C1q for 4 hrs and treated with 20ng/ml LPS and co-cultured with apoptotic Jurkat cells at a 1:3 ratio of BMDM to apoptotic cells, 5 separate cultures of BMDM adhered to HSA for 18 hrs, 5 separate cultures of BMDM adhered to C1q for 18 hrs, 5 separate cultures of BMDM adhered to HSA for 18 hrs and infected with M avium at a 1:500 ratio of BMDM to M avium, 5 separate cultures of BMDM adhered to C1q for 18hrs and infected with M avium at a 1:500 ratio of BMDM to M avium, 5 separate cultures of BMDM adhered to HSA for 18 hrs and infected with M avium at a 1:1000 ratio of BMDM to M avium. The chip utilized for these studies is a mouse whole-genome 12-plex expression microarray design by NimbleGen designed from the MM9 genome Candidate probe sequences were verified to have no cross-hybridization to human (HG19) or Mycobacterium avium (NC_008595) targets Note: Study sample BMDM_HSA & M avium (1:500)_18hr_rep2 was not included in this submission due to quality control concerns.
Project description:To investigate the effect pf PD-1 knockout during Mtb infection, wild type mice and PD-1 knockout mice were infected with Mtb and BMDC were isolated for the transcriptome analysis.
Project description:We examined the microRNA profiles of THP-1 macrophages upon the MTB infection of (1) Beijing/W and non-Beijing/W clinical strains, and (2) susceptible and multidrug-resistant (MDR-) MTB strains.
Project description:Global gene expressions of Mtb-infected mouse lungs were compared between with and without PDE4 inhibitor treatment. A lot of host genes are differentially expressed 21d and 28d post-Mtb infection. PDE4 inhibitor, however, downregulate 10% of genes among those and genes differentially regulated by PDE4 inhibitor are mainly involved immune response. Total RNA was isolated from Mtb-infected mouse lungs with or without CC-3052 (25 mg/kg/day) using Trizol reagent and gene profile was analyed using Affymetrix mouse ST 1.0