Effect Of ω-3 Polyunsaturated Fatty Acids On Dendritic Cells From Human Peripheral Blood

Objective:ω-3 polyunsaturated fatty acids (ω-3 PUFAs) is a small molecule which is an important part of its main components in immune nutrition, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Dendritic cells (DCs) can activate immune rejection and induce immune tolerance. It is an effective way to prolong graft survival according to tolerance induction by DCs. In this study, we cultured the monoeyte-derived DCs in vitro, observed cell morphology, detected cytokine and immuno-phenotype. We discussed the role ofω-3 PUFAs on the dendritic cell maturation and immune function. Methods:The samples of healthy adult peripheral blood was gradient separated by lymphocyte separation medium. The mononuclear cells was obtained by middle white film cells which is obtained by adherenting to cell wall,then added some materials containing 10% fetal bovine serum RPMI 1640 complete medium, recombinant human colony-stimulating factor (rhGM-CSF), recombinant human interleukin-4 (rhIL-4) to a final concentration of:rhGM-CSF 500U/ml, rhIL-4250U/ml. Medium was changed every other day and a half, induced 5 days.Then we can obtained immature dendritic cells (imDC). EPA, DHA or SA treated cells 24h, and will be divided into 5 groups:immature DCs group, mature DCs group, EPA treatment group, DHA treatment group and SA treatment group. After Endotoxin lipopoly-saccharide (LPS) induced cell maturation, the cells seeded Wright-Giemsa staining of DCs in each group form; detected DCs costimulatory molecule CD80mRNA, CD86mRNA and surface antigen-presenting molecule HLA-DR mRNA expression by semi-quantitative RT-PCR; detected cell supernatant of each group of interleukin-12 (IL-12) and tumor necrosis factor-a (TNF-a) levels by enzyme linked immunosorbent assay (ELISA). Results:The relative expression quantities of CD80mRNA, CD86mRNA and HLA-DRmRNA in immature DCs group was 0.369±0.023, 0.573±0.033,0.467±0.020 respectively. Mature DCs expressed high level of costimulatory molecules and HLA-DR. The relative expression quantities of CD80mRNA, CD86mRNA and HLA-DRmRNA in mature DCs group was 0.767±0.017,1.160±0.047,0.801±0.016 respectively; The relative expression quantities of CD80mRNA, CD86mRNA and HLA-DRmRNA in EPA group and DHA group was 0.547±0.034,0.849±0.043,0.657±0.023 and 0.465±0.032, 0.875±0.042,0.619±0.019. Compared with mature DCs group, they decreased obviously (P<0.01). The relative expression quantities of CD80mRNA, CD86mRNA and HLA-DRmRNA in SA-treated DCs group was 0.757±0.020, 1.132±0.064,0.792±0.018 respectively, Compared with mature DCs group,they had no difference (P>0.05). The levels of IL-12P70 and TNF-a in 5 different DCs groups were 190.73±16.26,768.05±62.73,358.71±52.79,412.63±62.64, 709.48±47.81 and 637.61±38.40,2405.73±125.48,1605.64±138.39,1807.38±140.34,2353.34±194.74 pg/ml respectively. The levels of IL-12P70 and TNF-a EPA-and DHA-treated DCs group were decreased significantly as compared with those in mature DCs group (P<0.01).Compared with mature DCs group, SA-treated DCs group had no difference (P> 0.05). Conclusion:ω-3 polyunsaturated fatty acids can reduce dendritic cell costimulatory molecules CD80, CD86 and surface antigen-presenting molecule HLA-DR expression in vitro, reduce cytokine Interleukin-12 and tumor necrosis factor-a release, decrease dendritic cells capability in antigen presentation, inhibit the maturation of dendritic cells and enhance the immune tolerance.All of those suggested thatω-3 polyunsaturated fatty acids could reduce organ transplant rejection.