The bovine papillomavirus type 1 E6 oncoprotein sensitizes cells to tumor necrosis factor alpha-induced apoptosis

In this report, we show that ionizing radiation (IR) at a clinically relevant dose (4 Gy) causes apoptosis in macrovascular and microvascular human endothelial cells. Treatment of irradiated cells with a low dose of bacterial endotoxin (LPS), similar to the levels observed in serum during endotoxemia, enhanced the rate of apoptosis, although LPS alone was unable to induce programmed cell death. The cytokine and endotoxin antagonist interleukin-10 (IL-10) reduced the rate of LPS + IR-induced apoptosis to levels obtained with irradiation alone. Using neutralizing antibodies against tumor necrosis factor- alpha (TNF), we could show crucial involvement of TNF in the LPS- mediated enhancement of IR-induced apoptosis, but not in the IR-induced apoptosis per se. However, further analysis strongly suggested the transmembrane form of TNF (mTNF), but not soluble TNF, to be accountable for the LPS-mediated cytotoxic effects. Studies with anatagonistic receptor specific antibodies clearly showed that TNF receptor type I (TR60) is essential and sufficient to elicit this effect. These findings are of potential clinical importance because they may disclose a relevant mechanism that leads to endothelial damage after radiotherapy or total body irradiation used for conditioning in bone marrow transplantation and that may thus contribute to transplant related complications, especially in association with endotoxemia or related inflammatory states.

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Tumor necrosis factor alpha-receptor type 1 activation in the hypothalamic paraventricular nucleus contributes to glutamate signaling and angiotensin II-dependent hypertension

Journal of Neuroscience ◽

10.1523/jneurosci.2360-19.2020 ◽

2020 ◽

pp. JN-RM-2360-19

Author(s):

Clara Woods ◽

Jose Marques-Lopes ◽

Natalina H. Contoreggi ◽

Teresa A. Milner ◽

Virginia M. Pickel ◽

...

Keyword(s):

Angiotensin Ii ◽

Tumor Necrosis Factor ◽

Tumor Necrosis Factor Alpha ◽

Paraventricular Nucleus ◽

Tumor Necrosis ◽

Necrosis Factor Alpha ◽

Glutamate Signaling ◽

Factor Alpha ◽

Necrosis Factor

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Tumor Necrosis Factor Alpha-Induced Apoptosis Requires p73 and c-ABL Activation Downstream of RB Degradation

Molecular and Cellular Biology ◽

10.1128/mcb.24.10.4438-4447.2004 ◽

2004 ◽

Vol 24 (10) ◽

pp. 4438-4447 ◽

Cited By ~ 45

Author(s):

B. Nelson Chau ◽

Tung-Ti Chen ◽

Yisong Y. Wan ◽

James DeGregori ◽

Jean Y. J. Wang

Keyword(s):

Tumor Necrosis Factor ◽

Tumor Necrosis Factor Alpha ◽

Tumor Necrosis ◽

Wild Type ◽

Necrosis Factor Alpha ◽

Abl Tyrosine Kinase ◽

Tnf Α ◽

Factor Alpha ◽

Induced Apoptosis ◽

Necrosis Factor

ABSTRACT The retinoblastoma protein (RB) suppresses cell proliferation and apoptosis. We have previously shown that RB degradation is required for tumor necrosis factor alpha (TNF-α) to induce apoptosis. We show here the identification of two apoptotic effectors, i.e., c-ABL tyrosine kinase and p73, which are activated by TNF-α following RB degradation. In cells expressing a degradation-resistant RB protein (RB-MI), TNF-α does not activate c-ABL. RB-MI also inhibits TNF-α-mediated activation of p73. Genetic deletion and pharmacological inhibition of c-ABL or p73 diminish the apoptotic response to TNF-α in human cell lines and mouse fibroblasts. Thymocytes isolated from RbMI/MI , Abl −/−, or p73 −/− mice are resistant to TNF-α-induced apoptosis compared to their wild-type counterparts. This is in contrast to p53 −/− thymocytes, which exhibit a wild-type level of apoptosis in response to TNF-α. Thus, c-ABL and p73 contribute to apoptosis induced by TNF-α, in addition to their role in promoting DNA damage-associated cell death.

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Neutralization of Tumor Necrosis Factor Alpha Suppresses Antigen-Specific Type 1 Cytokine Responses and Reverses the Inhibition of Mycobacterial Survival in Cocultures of Immune Guinea Pig T Lymphocytes and Infected Macrophages

Infection and Immunity ◽

10.1128/iai.73.12.8437-8441.2005 ◽

2005 ◽

Vol 73 (12) ◽

pp. 8437-8441 ◽

Cited By ~ 12

Author(s):

Hyosun Cho ◽

David N. McMurray

Keyword(s):

Tumor Necrosis Factor ◽

Tumor Necrosis Factor Alpha ◽

Tumor Necrosis ◽

T Cell Response ◽

Interleukin 12 ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Factor Alpha ◽

Necrosis Factor

ABSTRACT Neutralization of tumor necrosis factor alpha (TNF-α) significantly down-regulated antigen-induced lymphoproliferation and the expression of interleukin-12 p40 and gamma interferon mRNA and enhanced the viability of intracellular attenuated and virulent mycobacteria in cocultures of immune T cells and macrophages obtained from Mycobacterium bovis BCG-vaccinated guinea pigs. This suggests the crucial role of TNF-α in the activation of a type 1 T-cell response against Mycobacterium tuberculosis infection.

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