Inhibitory effect of dietary n-3 polyunsaturated fatty acids to intestinal IL-15 expression is associated with reduction of TCRalphabeta+CD8alpha+CD8beta-intestinal intraepithelial lymphocytes.
Intestinal intraepithelial lymphocytes (IELs) and their cytokines play an important role in the regulation of gut immune response and take part in gut immune barrier function. n-3 polyunsaturated fatty acid (PUFA) is an immunoregulator that has been shown to influence the process of gut inflammation. Interleukin (IL)-15 is a T-cell growth factor that has been shown to influence the differentiation of IEL. The aim of this study was to analyze the effects of dietary n-3 PUFA on IEL. IEL phenotype and cytokine (TNF-alpha, IFN-gamma, IL-4, IL-10 and TGF-beta1) profile were measured by FACS and real-time RT-PCR in healthy adult rats fed with fish oil diet for 90 days. Rats fed with corn oil diet served as controls. Intestinal IL-15 expression was measured by immunohistochemistry and real-time RT-PCR. The results demonstrated a decrease of intestinal IL-15 expression in the fish oil group. Associated with this deduction, n-3 PUFA significantly decreased the proportion of TCRalphabeta+CD8alpha+CD8beta- cells and IEL-derived TNF-alpha, IFN-gamma, IL-4 and IL-10. In conclusion, n-3 PUFA could inhibit intestinal mucosal expression of IL-15 and may influence phenotype and function of IEL through this mechanism.
Wang
Jian
J
Department of Surgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 21002, China.
Zhang
Haiyun
H
Ma
Hao
H
Lu
Bin
B
Wang
Jinhua
J
Li
Yousheng
Y
Li
Jieshou
J
D000818:Animals; D016827:CD8 Antigens / Q000502:physiology*; D016207:Cytokines / Q000096:biosynthesis; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage / Q000494:pharmacology*; D019409:Interleukin-15 / Q000096:biosynthesis*; D007413:Intestinal Mucosa / Q000166:cytology; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology*; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000502:physiology*
D016827:CD8 Antigens; C409469:CD8 antigen, alpha chain; C531085:CD8beta antigen, rat; D016207:Cytokines; D015525:Fatty Acids, Omega-3; D019409:Interleukin-15; D016693:Receptors, Antigen, T-Cell, alpha-beta