神经肽P物质对小鼠脾NK细胞迁移及趋化因子受体表达的影响

Effects of neuropeptide substance P on migration and chemokine receptor expression in the NK cells of mouse spleen

探讨神经肽P物质(substance P,SP)对小鼠NK细胞迁移能力和趋化因子受体表达的影响,揭示SP对NK细胞迁移功能的调节作用。采用Transwell法检测SP对C57BL/6小鼠脾NK细胞迁移活性的影响;实时荧光定量PCR检测趋化因子受体(CCR5、CXCR4)的mRNA表达水平;流式细胞术检测趋化因子受体(CCR5、CXCR4)的膜表达水平。结果显示,选用10^(-14)～10^(-6)mol/L SP处理小鼠脾NK细胞,在较低浓度范围内,NK细胞迁移作用随着SP浓度的升高而增强;在较高浓度范围内,NK细胞迁移作用随着SP浓度的升高而回落至基础水平。在所选浓度范围内,SP均可增加CCR5 mRNA和CXCR4 mRNA表达;受较低浓度SP刺激后,CCR5和CXCR4表达阳性细胞数随SP浓度升高而逐渐增加,而受较高浓度SP刺激后,CCR5和CXCR4表达阳性细胞数随SP浓度升高而逐渐回降,该趋势与SP促进NK细胞趋化活性的作用趋势基本一致。这些结果提示SP对NK细胞具有直接趋化作用,且SP对某些趋化因子受体的表达有一定的调节作用,这些趋化因子受体的表达可能参与了SP对NK细胞迁移活动的调控。

The purpose of this study was to investigate effects of neuropeptide substance P(SP)on the expression of chemokine receptors and cell migration of murine NK cells.The effects of SP on migration of splenic NK cells from C57 BL/6 mice were assayed by cell migration assay.The expression of chemokine receptors CCR5 and CXCR4 was detected by real-time fluorescent quantitative PCR and flow cytometry.The splenic NK cells were treated with SP in the range of 10-14 to 10-6 mol/L.In the lower concentration range,migration of NK cells increased with increase of SP concentration,whereas in the higher concentration range,migration of NK cells decrease to the basal level as the SP concentration increased.In all the selected concentration range,SP increased the mRNA expression of CCR5 and CXCR4.SP in lower concentration range gradually increased the number of CCR5 and CXCR4 positive cells following the increase of SP concentration,but SP in higher concentration range decreased the number of CCR5 and CXCR4 positive cells with the increase of SP concentration.This trend was consistent with effects of SP on NK cell migration activity.These results suggest that SP has a regulatory role in cell migration and expression of chemokine receptors of NK cells,and the expression of these chemokine receptors may be involved in the regulation of migration of NK cell by SP.