Medical Microbiology Commons^™

Avirulent Strains Of Toxoplasma Gondii Infect Macrophages By Active Invasion From The Phagosome, Yanlin Zhao, Andrew H. Marple, David J. P. Ferguson, David J. Bzik, George S. Yap

Dartmouth Scholarship

Unlike most intracellular pathogens that gain access into host cells through endocytic pathways, Toxoplasma gondii initiates infection at the cell surface by active penetration through a moving junction and subsequent formation of a parasitophorous vacuole. Here, we describe a noncanonical pathway for T. gondii infection of macrophages, in which parasites are initially internalized through phagocytosis, and then actively invade from within a phagosomal compartment to form a parasitophorous vacuole. This phagosome to vacuole invasion (PTVI) pathway may represent an intermediary link between the endocytic and the penetrative routes for host cell entry by intracellular pathogens. The PTVI pathway is preferentially …

Expression And Function Of Hypoxia Inducible Factor-1 Alpha In Human Melanoma Under Non-Hypoxic Conditions, Caroline N. Mills, Sandeep S. Joshi, Richard M. Niles

Richard M. Niles

Background Hypoxia inducible factor-1 alpha (HIF-1α) protein is rapidly degraded under normoxic conditions. When oxygen tensions fall HIF-1α protein stabilizes and transactivates genes involved in adaptation to hypoxic conditions. We have examined the normoxic expression of HIF-1α RNA and protein in normal human melanocytes and a series of human melanoma cell lines isolated from radial growth phase (RGP), vertical growth phase (VGP) and metastatic (MET) melanomas. Results HIF-1α mRNA and protein was increased in RGP vs melanocytes, VGP vs RGP and MET vs VGP melanoma cell lines. We also detected expression of a HIF-1α mRNA splice variant that lacks part …

Expression And Function Of Hypoxia Inducible Factor-1 Alpha In Human Melanoma Under Non-Hypoxic Conditions, Caroline N. Mills, Sandeep S. Joshi, Richard M. Niles

Biochemistry and Microbiology

Background

Hypoxia inducible factor-1 alpha (HIF-1α) protein is rapidly degraded under normoxic conditions. When oxygen tensions fall HIF-1α protein stabilizes and transactivates genes involved in adaptation to hypoxic conditions. We have examined the normoxic expression of HIF-1α RNA and protein in normal human melanocytes and a series of human melanoma cell lines isolated from radial growth phase (RGP), vertical growth phase (VGP) and metastatic (MET) melanomas.

Results

HIF-1α mRNA and protein was increased in RGP vs melanocytes, VGP vs RGP and MET vs VGP melanoma cell lines. We also detected expression of a HIF-1α mRNA splice variant that lacks part …

Corr4a And Vrt325 Do Not Reduce The Inflammatory Response To P. Aeruginosa In Human Cystic Fibrosis Airway Epithelial Cells, Laleh Talebian, Bonita Coutermarsh, Jacqueline Y. Channon, Bruce A. Stanton

Dartmouth Scholarship

P. aeruginosa chronically colonizes the lung in CF patients and elicits a proinflammatory response. Excessive secretion of IL-6 and IL-8 by CF airway cells in response to P. aeruginosa infection in the CF airway is though to contribute to lung injury. Accordingly, the goal of this study was to test the hypothesis that Corr4a and VRT325, investigational compounds that increase ΔF508-CFTR mediated Cl⁻ secretion in human CF airway cells, reduce the pro-inflammatory response to P. aeruginosa.

Marek's Disease Virus (Mdv) Encodes An Interleukin-8 Homolog (Vil-8): Characterization Of The Vil-8 Protein And A Vil-8 Deletion Mutant Mdv, Mark S. Parcells, Su-Fang Lin, Robert L. Dienglewicz, Vladimir Majerciak, Dan R. Robinson, Hua-Chien Chen, Zining Wu, George R. Dubyak, Peter Brunovskis, Henry D. Hunt

Dartmouth Scholarship

Chemokines induce chemotaxis, cell migration, and inflammatory responses. We report the identification of an interleukin-8 (IL-8) homolog, termed vIL-8, encoded within the genome of Marek's disease virus (MDV). The 134-amino-acid vIL-8 shares closest homology to mammalian and avian IL-8, molecules representing the prototype CXC chemokine. The gene for vIL-8 consists of three exons which map to the BamHI-L fragment within the repeats flanking the unique long region of the MDV genome. A 0.7-kb transcript encoding vIL-8 was detected in an n-butyrate-treated, MDV-transformed T-lymphoblastoid cell line, MSB-1. This induction is essentially abolished by cycloheximide and herpesvirus DNA polymerase inhibitor phosphonoacetate, indicating …