降钙素基因相关肽诱导人单核细胞合成趋化因子白细胞介素8的研究

Calcitonin gene-related peptide induces chemokine interleukine-8 synthesis in human monocytes

目的 探讨神经肽对免疫细胞的神经免疫调节作用。方法 以人单核细胞株为体外实验模型 ,将降钙素基因相关肽 (CGRP)作用于脂多糖活化的单核细胞 ,用ELISA测定其分泌趋化因子白细胞介素 8(IL 8) ,采用逆转录多聚酶联链反应 (RT PCR)检测IL 8mRNA的表达 ,利用 4 8孔微型趋化小室分析单核细胞对中性粒细胞和淋巴细胞的趋化活性 ,并通过受体拮抗剂CGRP8 37了解CGRP对人单核细胞趋化功能的调节作用。结果 CGRP诱导活化的单核细胞分泌表达IL 8蛋白(112 0pg/ml± 15pg/ml)和IL 8mRNA增加 (IL 8/肌动蛋白比值为 1 84 5± 0 5 87) ,用受体拮抗剂CGRP8 37后IL 8减少 (6 70pg/ml± 15pg/ml) ,IL 8/肌动蛋白比值为 1 339± 0 4 34。CGRP增加活化的单核细胞对中性粒细胞和淋巴细胞的趋化活性 ,其趋化指数分别是CI =3 78± 0 0 8和CI =3 4± 0 2 7;受体拮抗剂CGRP8 37则使趋化作用减弱。结论 外周感觉神经末梢的神经肽CGRP通过受体介导 ,作用于单核细胞 ,在一定条件下诱导其合成和分泌趋化因子IL 8。

Objective To study the effect of calcitonin gene related peptide (CGRP) on the function of immune cells. Methods Human monocytes were cultured with calcitonin gene related peptide in vitro and activated with lipopolysaccharide (LPS). The IL 8 level in the supernatant was measured with ELISA and the IL 8 mRNA expression in monocytes was observed by reverse transcription polymerase chain reaction (RT PCR). The chemotactic activity of monocytes to neutrophils and lymphocytes was analyzed with micro chemotacxis chamber. Chemotactic index (CI) was calculated by the formula: number of monocytes migrating to the underside of membrane in the LPS+CGRP group/ number of monocytes migrating to the underside of membrane in the control group. CGRP receptor antagonist CGRP8 37 was added into the culture to study the effect of CGRP. Blank control and cultures of monocytes with LPS or with CGRP only were used as controls. Results The level of IL 8 protein in the supernatant of the LPS+CGRP group was 1 120 pg/ml±14.80 pg/ml, significantly higher than those in other groups (670 pg/ml±15.10 pg/ml in LPS+CGRP+CGRP8 37 group). The expression of IL 8 mRNA in the LPS+CGRP group was the highest(IL 8/β actin=1.845±0.587), IL 8/ β actin in the LPS+CGRP+CGRP8 37 group was1.339±0.434 . The chemotactic activities of the monocytes to neutrophils and lymphocytes were enhanced in the LPS+CGRP group(CI=3.78±0.08 to neutrophils and CI=3.4±0.27 to lymphocytes). The CI values were 1.15±0.31 and 1.21±0.06 respectively in the LPS+CGRP+CGRP 8 37 group. Conclusion CGRP in the peripheral nerve ending induces monocytes to synthtize and secret chemotactic factor IL 8 and enhance the chemotactic activity of monocytes, thus promoting the directional migration and aggregation of neutrophils and lymphocytes to foci of inflammation.