白细胞移动抑制因子(LMIF)释放的测定及条件性抑制LMIF的作用

An assay of leukocyte migration inhibitory factor(LMIF) and the conditioned suppression effect on LMIF

目的选用与迟发过敏（ＤＴＨ）反应密切相关的白细胞移动抑制因子（ＬＭＩＦ）的体外测定方法，分析在条件性免疫抑制反应中ＬＭＩＦ活性的变化。方法ＬＭＩＦ测定是以间接毛细管方法结合分光光度计，测定游出细胞的吸光度（Ａ值）。在条件性反应训练和建立ＤＴＨ反应模型的第７天，取耳称重，同时取小鼠肠系膜淋巴结细胞，制备ＬＭＩＦ。结果ＬＭＩＦ在条件反应组的作用明显减弱（Ａ值升高），与不经过条件性训练的对照组相比，差异有非常显著意义（Ｐ＜０．０１，方差分析，ｎ＝７），但与非条件反应组相比没有差异，说明已形成了条件性抑制ＬＭＩＦ的反应。结论本工作建立了稳定的ＬＭＩＦ吸光度检测法，建立了环磷酰胺条件性抑制ＬＭＩＦ的模型。

Objective Our previous work showed that a conditioned immunosuppressive response could be induced in mice by following procedures: Camphor odor and intraperitoneal injection of cyclophosphamide were used as conditioned and nonconditioned stimulus, respectively. DTH response was induced by smearing 2,4-dinitrochlorobenzene (DNCB) on the abdominal skin (sensitization) and on the left ear (challenge) 5 days after the sensitization. Our previous work also showed that when the serum from the conditioned mice was injected into normal mice, DTH response was found to be suppressed significantly, indicating that a suppressive element existed in the conditioned serum. We in the present study want to build up a conditioned DTH response model in vitro so as to further analyze the property of this suppressive element. Methods With capillary incubation and EIA reader, the role of LMIF was judged by measuring the optical density (OD value) of migrated leukocyte. The procedures of conditioned response and DTH response were same as before except for the LMIF preparation. On the 7th day, the lymphocytes from the mice were stimulated with phytohemagglutinin(PHA) and then the OD value was measured. Results The OD value was increased both in conditioned group ( P< 0.01 as compared with control group) and in nonconditioned group ( P <0.05 as compared with control group), but there was no significant difference between the conditioned group and the nonconditioned group. Conclusions An improved assay of LMIF has been developed and that a model of conditioned LMIF response in vitro has been established. This model could be used for the analysis about the mechanism of the conditioned serum.