Étude de l'immunité intestinale de la truite arc-en-ciel (Oncorhynchus mykiss) et perspectives de modulation par des additifs alimentaires : approches cellulaires et moléculaires

Abstract : The impact of nutrition on rainbow trout intestinal immunity, a farmed fish with high economic value, remains unclear. Consequently, the objectives of this thesis were to better characterize the intestinal immune system of that fish and to determine if it is possible to modulate its intestinal immune response by dietary free nucleotides. Our results show that intestinal phagocytes are less activated by yeast cells but when they are activated they can ingest as many yeast cells as their head kidney (HK) counterparts. We noted that the natural cytotoxic activity of intestinal leukocytes is twice higher than the one of HK leukocytes. This natural cytotoxic activity is correlated with an increase of transcripts encoding the natural killer enhancement factor (NKEF). Intestinal leukocytes did not respond to an in vitro mitogenic stimulation. This lack of response is not due to apoptosis. We also observed a high expression of CD8a and CD3 transcripts in gut leukocytes, suggesting that the intestine could contain a high proportion of T cells expressing the aa homodimeric form of CD8. Finally, we observed that dietary free nucleotides stimulate the spontaneous proliferation and the phagocytic activity of intestinal leucocytes in vitro. However, they did not modulate natural cytotoxicity activity nor did they affect the amounts of transcripts encoding specific markers of T and B lymphocytes and inflammatory cytokines. In the future, it will be interesting to repeat these experiments using infected fish in order to study the effect of nucleotides on the inflammatory and specific immune responses
Document type :
Theses
Complete list of metadatas

Cited literature [146 references]  Display  Hide  Download

https://hal.univ-lorraine.fr/tel-01750165
Contributor : Thèses Ul <>
Submitted on : Thursday, March 29, 2018 - 12:39:51 PM
Last modification on : Wednesday, August 29, 2018 - 10:29:39 AM

File

DDOC_T_2013_0125_MARTIN.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01750165, version 1

Collections

Citation

Ève Martin. Étude de l'immunité intestinale de la truite arc-en-ciel (Oncorhynchus mykiss) et perspectives de modulation par des additifs alimentaires : approches cellulaires et moléculaires. Biologie animale. Université de Lorraine, 2013. Français. ⟨NNT : 2013LORR0125⟩. ⟨tel-01750165⟩

Share

Metrics

Record views

44

Files downloads

48