Issue |
Vet. Res.
Volume 36, Number 2, March-April 2005
|
|
---|---|---|
Page(s) | 229 - 240 | |
DOI | https://doi.org/10.1051/vetres:2004058 | |
How to cite this article | Vet. Res. (2005) 229-240 |
DOI: 10.1051/vetres:2004058
NF-
B inhibition accelerates apoptosis
of bovine neutrophils
Sofie Notebaert, Luc Duchateau and Evelyne Meyer Department of Physiology, Biochemistry and Biometrics, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
(Received 13 August 2004; accepted 14 October 2004)
Abstract - Apoptosis is one of the major events that contribute to the regulation of the immune system. For human neutrophils, evidence
has been produced that the transcription factor NF-
B is critical in influencing the ultimate outcome of a cell's fate. However, such research has not yet been performed on bovine
neutrophils. This urged us to examine the possible involvement of NF-
B in apoptosis of these cells. At first, we investigated whether p65 and p50, the most important members of the NF-
B family, are expressed in isolated blood neutrophils. The presence of both members was demonstrated on the RNA and protein
level. Then the effect on bovine neutrophil apoptosis of gliotoxin, a potent and specific inhibitor of NF-
B, was examined. The rate of constitutive apoptosis was found to be greatly accelerated by inhibition of NF-
B. Furthermore, gliotoxin dramatically augmented the limited pro-apoptotic effect of TNF-
, an important inflammatory mediator. The results were obtained in six cows by annexin-V-FITC staining of externalized phosphatidylserine
and subsequent flow cytometric analysis. Additional measurement of caspase-3/7 activity and evaluation of morphological criteria
confirmed the outcome of this experiment. Finally, NF-
B activity was assessed under these conditions. The activity of p50 was found to be minimally affected by gliotoxin, while
significantly lower active p65 values were observed. Still, the highest percentage of apoptosis, which was caused by incubation
with both gliotoxin and TNF-
, did not correspond to the lowest activity of p65. We conclude that NF-
B p65 promotes the survival of bovine neutrophils by delaying the initiation of apoptosis.
Key words: bovine neutrophil / NF-

Corresponding author: Evelyne Meyer Evelyne.Meyer@UGent.be
© INRA, EDP Sciences 2005