Please Note:

The Open Access Repository will be moving to a new authentication system on the 1st of November.

From this date onwards, account holders will be required to login using their University of Tasmania credentials.
If your current repository username differs from your University username, please email E.Prints@utas.edu.au so we can update these details on your behalf.

Due to the change, there will be a short outage of the repository from 9am on the morning of the 1st of November

Open Access Repository

Molecular cloning and expression analysis of tumour necrosis factor-alpha in amoebic gill disease (AGD)-affected Atlantic salmon (Salmo salar L.)

Downloads

Downloads per month over past year

Morrison, RN and Zou, J and Secombes, CJ and Scapigliati, G and Adams, MB and Nowak, BF (2007) Molecular cloning and expression analysis of tumour necrosis factor-alpha in amoebic gill disease (AGD)-affected Atlantic salmon (Salmo salar L.). Fish and Shellfish Immunology, 23 (5). pp. 1015-1031. ISSN 1050-4648

[img] PDF
4195.pdf | Request a copy
Full text restricted
Available under University of Tasmania Standard License.

Abstract

Tumour necrosis factor-alpha (TNF-a) is a key mediator of inflammation during amoebiasis of humans and mice. Atlantic
salmon (Salmo salar L.) are also susceptible to infection by amoebae (Neoparamoeba spp.), inflicting a condition known as amoebic
gill disease (AGD). Here, the role of TNF-a in AGD-pathogenesis was examined. Two Atlantic salmon TNF-a transcripts designated
TNF-a1 and TNF-a2 together with their respective genes were cloned and sequenced. TNF-a1 is 1379 bp and consists of
a 738 bp open reading frame (ORF) translating into a predicted protein of 246 amino acids. TNF-a2 is 1412 bp containing an ORF
and translated protein the same lengths as TNF-a1. An anti-rainbow trout TNF-a polyclonal antibody that bound recombinant
Atlantic salmon TNF-a1 and TNF-a2 was used to detect constitutive and inducible expression of TNF-a in various tissues. The
anti-TNF-a antibody bound to a TNF-like protein z60 kDa that was constitutively expressed in a number of tissues in healthy
Atlantic salmon. However, this protein was not detected in lysates from mitogen-stimulated head kidney leucocytes, despite up-regulation
of TNF-a mRNAs under the same conditions. During the early onset of AGD in Atlantic salmon, there were no demonstrable
differences in the gill tissue expression of TNF-a1, TNF-a2 nor the interleukin-1 beta (IL-1b), inducible nitric oxide synthase (iNOS)
and interferon gamma (IFN-g) mRNAs compared to tissue from healthy fish. In Atlantic salmon with advanced AGD, IL-1b but not
TNF-a1 or TNF-a2 mRNAs was up-regulated and was lesion-restricted. Given that Neoparamoeba spp. modulated both TNF-a2 and
IL-1b in head kidney leucocytes in vitro, it appears that rather than being recalcitrant to Neoparamoeba spp.-mediated TNF-a expression,
either the parasite can influence the cytokine response during infection, there is ineffective signalling for TNF-a expression, or
there are too few cells at the site of infection with the capacity to produce TNF-a. These data support our previous observation that
IL-1b mRNA expression is up-regulated in AGD-affected tissue and that TNF-a is not intrinsic in AGD-pathogenesis.

Item Type: Article
Keywords: TNF-a; IL-1b; Atlantic salmon; Amoebic gill disease
Journal or Publication Title: Fish and Shellfish Immunology
Publisher: Academic Press
Page Range: pp. 1015-1031
ISSN: 1050-4648
Identification Number - DOI: 10.1016/j.fsi.2007.04.003
Additional Information:

The definitive version is available at http://www.sciencedirect.com

Date Deposited: 07 Apr 2008 14:27
Last Modified: 18 Nov 2014 03:34
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page
TOP