Adenovirus-Mediated Expression of a Dominant Negative Mutant of p65/RelA Inhibits Proinflammatory Gene Expression in Endothelial Cells Without Sensitizing to Apoptosis

• Published in: The Journal of immunology (1950) Vol. 161; no. 9; pp. 4572 - 4582
• Main Authors: Soares, Miguel P, Muniappan, Ashok, Kaczmarek, Elzbieta, Koziak, Katarzyna, Wrighton, Christopher J, Steinhauslin, Florence, Ferran, Christiane, Winkler, Hans, Bach, Fritz H, Anrather, Josef
• Format: Journal Article
• Language: English
• Published: United States Am Assoc Immnol 01.11.1998
• Subjects: Adenoviridae - genetics; Animals; Apoptosis - genetics; Cells, Cultured; Cysteine Endopeptidases; DNA-Binding Proteins - biosynthesis; DNA-Binding Proteins - genetics; DNA-Binding Proteins - physiology; Endothelium, Vascular - cytology; Endothelium, Vascular - metabolism; Gene Expression Regulation; Genes, Dominant; Genetic Vectors - genetics; Homeodomain Proteins; Humans; I-kappa B Proteins; Intracellular Signaling Peptides and Proteins; Mice; Minor Histocompatibility Antigens; NF-kappa B - antagonists & inhibitors; NF-kappa B - genetics; NF-kappa B - physiology; NF-KappaB Inhibitor alpha; Nuclear Proteins; Organ Specificity; Protein Biosynthesis; Proteins - genetics; Proto-Oncogene Proteins c-bcl-2; Proto-Oncogene Proteins c-myc - biosynthesis; Proto-Oncogene Proteins c-myc - genetics; Recombinant Fusion Proteins - physiology; Replication Protein C; Repressor Proteins; Saccharomyces cerevisiae Proteins; Sequence Deletion; Superoxide Dismutase - biosynthesis; Superoxide Dismutase - genetics; Swine; Transcription Factor RelA; Transcription, Genetic; Transfection; Transgenes; Tumor Necrosis Factor alpha-Induced Protein 3
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.161.9.4572

We hypothesized that blocking the induction of proinflammatory genes associated with endothelial cell (EC) activation, by inhibiting the transcription factor nuclear factor kappaB (NF-kappaB), would prolong survival of vascularized xenografts. Our previous studies have shown that inhibition of NF-kappaB by adenovirus-mediated overexpression of I kappaB alpha suppresses the induction of proinflammatory genes in EC. However, I kappaB alpha sensitizes EC to TNF-alpha-mediated apoptosis, presumably by suppressing the induction of the NF-kappaB-dependent anti-apoptotic genes A20, A1, manganese superoxide dismutase (MnSOD), and cellular inhibitor of apoptosis 2. We report here that adenovirus mediated expression of a dominant negative C-terminal truncation mutant of p65/RelA (p65RHD) inhibits the induction of proinflammatory genes, such as E-selectin, ICAM-1, VCAM-1, IL-8, and inducible nitric oxide synthase, in EC as efficiently as does I kappaB alpha. However, contrary to I kappaB alpha, p65RHD does not sensitize EC to TNF-alpha-mediated apoptosis although both inhibitors suppressed the induction of the anti-apoptotic genes A20, A1, and MnSOD equally well. We present evidence that this difference in sensitization of EC to apoptosis is due to the ability of p65RHD, but not I kappaB alpha, to inhibit the constitutive expression of c-myc, a gene involved in the regulation of TNF-alpha-mediated apoptosis. These data demonstrate that it is possible to block the expression of proinflammatory genes during EC activation by targeting NF-kappaB, without sensitizing EC to apoptosis and establishes the role of c-myc in controlling induction of apoptosis during EC activation. Finally, these data provide the basis for a potential approach to suppress EC activation in vivo in transgenic pigs to be used as donors for xenotransplantation.