Publications [#119317] of Bernard M Fischer

Papers Published

1. TM Krunkosky, BM Fischer, LD Martin, N Jones, NJ Akley, KB Adler, Effects of TNF-alpha on expression of ICAM-1 in human airway epithelial cells in vitro. Signaling pathways controlling surface and gene expression., American journal of respiratory cell and molecular biology, vol. 22 no. 6 (June, 2000), pp. 685-92, ISSN 1044-1549 [doi]
   (last updated on 2013/05/16)

   Abstract:
   Signaling pathways associated with tumor necrosis factor (TNF)-alpha-induced intercellular adhesion molecule 1 (ICAM-1) surface and gene expression were investigated in well differentiated normal human bronchial epithelial (NHBE) cells in air-liquid interface primary culture. Cells were exposed to human recombinant TNF-alpha (hrTNF-alpha; 0.015 to 150 ng/ml [specific activity, 2.86 x 10(7) U/mg]). TNF-alpha enhanced ICAM-1 surface expression (measured by flow cytometry) and steady-state messenger RNA (mRNA) levels (assessed by Northern hybridization) in concentration- and time-dependent manners. TNF-alpha-induced ICAM-1 surface and gene expression were both blocked by the RNA polymerase II inhibitor actinomycin D (0.1 microg/ml), and surface expression was attenuated by a neutralizing monoclonal antibody directed against the TNF-alpha receptor p55 (TNF-RI). The intracellular signaling pathway leading to enhanced expression appeared to involve activation of a phospholipase C that hydrolyzes phosphatidylcholine (PC-PLC) because D609, a specific PC-PLC inhibitor, attenuated TNF-alpha-induced increases in production of diacyl-glycerol (DAG), a hydrolysis product of PC-PLC, and also attenuated TNF-alpha enhancement of ICAM-1 surface and gene expression. Because DAG formed by action of PC-PLC can activate protein kinase C (PKC), involvement of PKC was investigated. The specific PKC inhibitor calphostin C blocked both surface and gene expression of ICAM-1 in response to TNF-alpha in a concentration-dependent manner. Finally, TNF-alpha stimulated binding of p65 and/or c-rel complexes to the nuclear factor (NF)-kappaB consensus binding site found on the ICAM-1 promoter, and binding of these complexes was inhibited by D609. The results support the following pathway, whereby TNF-alpha enhances expression of ICAM-1 in NHBE cells: TNF-alpha --> TNF-RI --> PC-PLC --> DAG --> PKC --> (NF-kappaB?) --> ICAM-1 mRNA --> ICAM-1 surface expression.

   Keywords:
   Antibodies, Monoclonal • Bronchi • Cell Line • Epithelial Cells • Flow Cytometry • Gene Expression • Humans • Intercellular Adhesion Molecule-1 • L-Lactate Dehydrogenase • NF-kappa B • Promoter Regions, Genetic • RNA Processing, Post-Transcriptional • RNA, Messenger • Respiratory Mucosa • Signal Transduction • Tumor Necrosis Factor-alpha • cytology • cytology* • enzymology • genetics • genetics* • immunology • immunology* • metabolism • pharmacology* • physiology