神经介素U在体外对猪淋巴细胞活性及自然杀伤细胞活性的影响

Effects of neuromedin U on lymphocytes and nature killer cell activities of pigs in vitro

[目的]本文旨在研究神经介素U(NMU)对猪外周血淋巴细胞(PBL)的免疫调节作用。[方法]以小梅山猪为研究对象,用半定量RT-PCR方法研究了猪PBL中NMU及其受体(NMUR1和NMUR^2)基因的表达,用免疫组织化学染色方法检测了猪PBL中NMU及其受体蛋白的分布,用Cell Counting Kit-8(CCK-8)细胞计数法研究了NMU对猪PBL细胞和NK细胞活性的影响。[结果]NMUR1 mRNA在猪PBL中表达,NMU和NMUR1蛋白在猪PBL的胞膜及胞浆均有分布。用不同浓度(0.01、0.1、1、10、100和1 000 nmol·L^(-1))NMU处理体外培养的PBL,与对照组相比,0.1、1和10 nmol·L^(-1)NMU极显著提高猪PBL的细胞活性(P<0.01),且当NMU浓度为10 nmol·L^(-1)时,PBL活性的水平达到峰值(179.4±3.0)%。用不同浓度(0.01、0.1、1、10、100和1 000 nmol·L^(-1))NMU处理体外培养的PBL细胞作为效应细胞,以K562细胞作为靶细胞。与对照组相比,在效靶比为15∶1时,0.1、1和10 nmol·L^(-1)的NMU均能显著提高NK细胞的细胞活性(P<0.01);效靶比为30∶1时,1和10 nmol·L^(-1)的NMU均能显著提高NK细胞的细胞活性(P<0.01);在效靶比为60∶1时,10 nmol·L^(-1)NMU能显著提高NK细胞的细胞活性(P<0.01)。[结论]NMU及NMUR1在猪PBL中均有表达,且NMU在一定浓度范围内能提高猪NK细胞对K562细胞的杀伤能力。

[ Objectives] The paper aims to investigate the role of neuromedin U （NMU）in immunoregulation on pig peripheral blood lymphocytes（PBL）. [ Methods ] The expression of NMU and its receptor（NMUR1 and NMUR2） mRNA and protein in pig peripheral blood lymphocytes（PBL） ,and the effects of NMU on lymphocytes and nature killer cell activities were studied in Xiaomeishan pigs by semiquantitative RT-PCR,immunohistochemistry and Cell Counting Kit-8（CCK-8） methods in vitro. [ Results ] Not only NMUR1 mRNA but also NMU and NMUR1 protein were all expressed in pig PBL. After pig PBL were treated with different doses of NMU,the cytoactive of the PBL was upregulated significantly by 0.1,1 and 10 nmol· L-1 NMU（P〈0.01 ）, with maximal effect at 10 nmol. L-1 NMU （179.4＋3.0） %. After pig NK cells were treated with different doses of NMU, compared with the control group,0.1,1 and 10 nmol. L-1 NMU significantly promoted cytotoxicity of NK cells at 15：1 ratio of effective cells to target cells（P〈0.01 ） ; 1 and 10 nmol·L-1 NMU significantly promoted cytotoxicity of NK cells at 30：1 ratio of effective cells to target cells （P〈0.01）, and 10 nmol· L-1 NMU significantly promoted cytotoxicity of NK cells at 60 ： 1 ratio of effective cells to target cells （P〈0.01）. [ Conclusions ] Our results demonstrated that NMU and NMU receptors were expressed in pigs PBLs and a certain concentration of NMU improved the capability of pig NK cells for killing K562 cells,which may be mediated by stimulating the proliferation of PBL,and this needs further study.