睾酮在体外对脾淋巴细胞增殖反应和分泌IgG的影响

为探讨雄激素对大鼠脾淋巴细胞产生免疫球蛋白和增殖反应的影响 ,用不同浓度睾酮作用于脾淋巴细胞 ,用中性红活染比色法和四甲基偶氮唑兰法 (MTT)分别观察睾酮对培养的大鼠脾淋巴细胞增殖的影响 ;用酶联免疫法 (ELISA)检测不同浓度睾酮处理的脾淋巴细胞由刀豆素A(ConA)刺激产生白细胞介素 6(IL- 6)和免疫球蛋白 (IgG)的影响。结果发现在睾酮作用下 ,细胞增殖反应下降 ;睾酮可下调脾淋巴细胞产生的IgG。提示睾酮在体外可以通过改变脾淋巴细胞增殖能力和产生的IgG来调节免疫反应     

噪声应激对大鼠淋巴细胞增殖功能和ACTH的影响

目的观察噪声应激对大鼠淋巴细胞增殖功能和血浆促肾上腺皮质激素(ACTH)的影响。方法将大鼠暴露于白噪声发生器输出放大的(100±1.5)dB(A)噪声中,检测不同噪声暴露时间(1、7、21d)大鼠淋巴细胞增殖功能和血浆中ACTH的变化。结果在接噪期间淋巴细胞增殖功能降低;血浆ACTH水平暴露1d后显著升高,连续暴露21d后显著降低。结论短期、长期噪声暴露均可抑制细胞免疫功能,其抑制机制可能与下丘脑-垂体-肾上腺(HPA)轴有关。     

镉对小鼠淋巴细胞增殖功能、IL-2影响与cAMP的关系

目的：观察镉对小鼠脾T淋巴细胞增殖功能、cAMP(环磷酸腺苷)、IL-2(白细胞介素-2)等的影响，探讨它们在镉的免疫毒性中作用和关系。方法：对BALB／C小鼠体外、体内染镉后，测定脾T淋巴细胞增殖功能、IL-2活性、cAMP含量等。结果：体内、体外染镉均引起了小鼠脾T淋巴细胞增殖功能、IL-2水平有剂量一效应关系的降低，两者的变化呈正直线相关。体内染镉引起IL-2水平对数的降低与cAMP水平的升高呈负直线相关。体外染镉引起T淋巴细胞增殖功能、IL-2水平的降低与cAMP水平升高呈负直线相关。结论：镉有抑制小鼠脾T淋巴细胞IL-2活性的免疫毒性作用；IL-2在镉抑制T淋巴细胞增殖活性中有重要作用；cAMP信使系统可能参与介导了镉对脾T淋巴细胞增殖功能、IL-2.     

CRF阻断镉对大鼠脾淋巴细胞免疫毒性的体外实验研究

目的：探讨体外镉的免疫功能抑制过程中促肾上腺皮质激素释放因子（CRF）的修饰调节作用。方法：离体培养大鼠脾淋巴细胞,用^3H-TdR掺入法测定分别在给氯化镉、CRF及两者联合作用条件下的T、B淋巴细胞的增殖转化功能。结果：镉抑制大鼠脾淋巴细胞的增殖转化,各染镉实验组T、B淋巴细胞增殖指数低于对照组（P＜0．05）;且有随剂量升高而而降低的趋势;1．0－100．0nmol/L CRF标准浓度组T、B淋巴细胞增殖指数明显高于对照组（P＜0．05）;当以1．0nmol/L CRF与5－20 μmol/L氯化镉联合作用时两种免疫细胞的增殖功能依然明显受到刺激,各实验组^3H-TdR掺入率高于对照组（P＜0．05）。结论：体外CRF能增强免疫细胞增殖活性并可阻断镉对T、B淋巴细胞的增殖抑制毒性。     

促肾上腺皮质激素释放因子对镉的淋巴细胞免疫毒性的体内外双向调节作用

目的 探讨体内外镉的免疫功能抑制过程中促肾上腺皮质激素释放因子（CRF）的修饰调节使用。方法 用垂体前叶细胞培养法测定中枢下丘脑和外周血浆CRF水平,用[^3H-TdR]掺入法分别检测体内、体外染毒的鼠脾T、B淋巴细胞增殖转化功能。结果 （1）整体实验动物各镉剂量组中枢下丘脑组织CRF水平均升高,有丝分裂原诱导脾T、B淋巴细胞增殖转化的刺激指数均低于对照组,差异有显著性（P＜0．05）;下丘脑CRF水平与T、B淋巴细胞增殖指数之间呈负相关关系（r＝－0．6750、－0．7560,P＜0．05）;外周血浆CRF水平各组间差异无显著性（P＜＞0．05。（2）体外染毒时,镉明显抑制大鼠脾淋巴细胞的增殖转化;1．0-100．0nmol/LCRF明显增强T、B淋巴细胞增殖转化能力;当以1．0nmol/LCRF与5－20μmol/L氯化镉联合作用对各实验组两种免疫组织[^3H-TdR]掺入率依然高于对照组,差异均有显著性（P＜0．05）。体内染镉时存在中枢组织CRF介导的免疫功能抑制性调节作用,但体外CRF却能增强免疫细胞活性并阻断镉对鼠脾淋巴细胞的直接免疫功能抑制。CRF对镉的淋巴细胞免疫毒性具有双向调节作用。     

亚砷酸钠对人淋巴细胞增殖抑制机制的实验研究

目的探讨亚砷酸钠(NaAsO2)对人淋巴细胞体外增殖抑制的影响。方法用不同浓度的NaAsO2处理细胞后,通过噻唑蓝还原法,吖啶橙荧光染色法和流式细胞术观察NaAsO2对淋巴细胞增殖的影响。结果NaAsO2低、中、高剂量对淋巴细胞增殖有抑制作用,荧光染色法测得凋亡率分别为10.07%、18.79%、28.35%。结论NaAsO2抑制淋巴细胞增殖,可能与其诱导凋亡有关。     

肝郁脾虚因素刺激对DMH诱发大肠癌大鼠免疫功能的影响

目的探讨肝郁脾虚因素刺激对二甲肼（DMH）诱发大鼠实验性大肠癌的发生及T淋巴细胞功能的影响，及用疏肝健脾方对动物模型进行防治。方法SD大鼠经肝郁脾虚因素刺激和DMI-120mg／kg颈部皮下注射，每周1次连续15周后停用MHC，预防和治疗组给予疏肝健脾方药2ml／只灌胃（2.0g/kg），大鼠分别在实验第9、14、19周取脾测定T淋巴细胞增殖和产生能力IFN-r和IL-2能力。结果SD大鼠经肝郁脾虚因素刺激和DMH作用下，与单纯DMH诱发大肠癌比较，单纯诱癌组T淋巴细胞增殖能力和产生IFN-r和IL-2能力的显著下降（P值分别＜0．005）；然而，经疏肝健脾方防治后，大鼠T淋巴细胞增殖能力和产生IFN-r和IL-2能力明显恢复。结论应用疏肝健脾方防治后能显著改善肝郁脾虚因素刺激对二甲肼诱发大鼠实验性大肠癌的发生及T淋巴细胞功能，能减轻大肠癌的发生发展过程。     

Ag85B蛋白诱导小鼠脾淋巴细胞表达IL-2、IFN-γ及促进细胞增殖的实验研究

目的探讨结核分枝杆菌Ag85B蛋白在体外诱导BALB/c小鼠脾淋巴细胞表达IL-2和IFN-γ的能力及对细胞增殖的影响,以了解Ag85B基因表达在特异性细胞免疫应答中的作用。方法体外分离培养BALB/c小鼠脾淋巴细胞,除去蛋白中的内毒素,采用BCA法对Ag85B蛋白进行定量,10μg/ml浓度的蛋白与小鼠脾淋巴细胞共同孵育24、72 h,RT-PCR方法检测细胞培养液上清中IL-2和IFN-γ的表达;用不同浓度的Ag85B蛋白刺激小鼠脾淋巴细胞24、48、72 h,MTT法检测其对小鼠脾淋巴细胞增殖能力的影响。结果小鼠脾淋巴细胞在体外分离培养成功;经RT-PCR检测,Ag85B蛋白能诱导小鼠脾淋巴细胞表达IL-2和IFN-γ,对照组表达呈阴性;MTT法检测到Ag85B蛋白对小鼠脾淋巴细胞的增殖具有促进作用,在一定范围内呈时间和剂量依赖性,在同对照组的增殖比较中,除0.5μg/ml组在24、48 h差异无统计学意义外,其他浓度组在各个时间点差异均有统计学意义(P0.05)。结论结核分枝杆菌Ag85B蛋白能诱导小鼠脾细胞产生IL-2和IFN-γ因子,能在体外促进小鼠脾淋巴细胞增殖,诱导了特异性的T细胞免疫应答。     

过氧化氢和环磷酰胺对辐射损伤小鼠脾淋巴细胞增殖的作用

目的：探讨化学因子对辐射损伤小鼠脾淋巴细胞增殖的影响。方法：采用^3H—TdR掺入法观察小鼠脾淋巴细胞增殖的变化。结果：与刀豆球蛋白A(Concanavalin A，Con A)同时作用于小鼠脾淋巴细胞的10^-6mol/L，和10^-5mol/L的H2O2对Con A刺激的小鼠脾淋巴细胞增殖有明显的促进作用，H2O2在Con A作用于小鼠脾淋巴细胞56h加入，H2O2对小鼠脾淋巴细胞增殖表现为抑制效应.当环磷酰胺(cyclophosphamide，CP)浓度≥10^-3mol/L和≥10^-3mol／L时，CP对脂多糖(lipopolysaccharide，LPS)和Con A刺激的小鼠脾淋巴细胞增殖分别表现为明显的抑制作用。当H2O2浓度≥10^-6mol／L和CP浓度≥10^-3mol／L时，H2O2和CP对辐射损伤的小鼠脾淋巴细胞增殖具有明显的抑制作用。结论：低浓度H2O2可以诱导小鼠脾淋巴细胞增殖的适应性反应，而H2O2联合CP不能诱导对辐射损伤小鼠脾淋巴细胞增殖的抗性．     

他莫昔芬对小鼠淋巴细胞功能的影响

[目的]研究他莫昔芬对小鼠淋巴细胞功能的影响.[方法]通过体外培养淋巴细胞,用MTT法分析他莫昔芬对小鼠淋巴细胞增殖及NK细胞杀伤活性的影响;用溶血空斑试验检测他莫昔芬对小鼠B淋巴细胞功能的影响. [结果]1、10、100、1 000 nmol/L他莫昔芬对小鼠T、B淋巴细胞增殖活性无明显增强或抑制作用(P＞0.05);1、10、100、1 000 nmol/L他莫昔芬显著增加小鼠溶血空斑形成细胞的数量(P<0.05);10、100、1 000 nmol/L他莫昔芬对小鼠NK细胞的杀伤活性有明显增强作用(P<0.01). [结论]他莫昔芬能增加小鼠溶血空斑形成细胞的数量和提高NK细胞的杀伤活性,对免疫功能有不同程度的调节作用.     

Effects of chromium on humoral and cell-mediated immune responses and host resistance to disease in a freshwater catfish, Saccobranchus fossilis (Bloch).

The effects of subtoxic levels of Cr on humoral and cell-mediated immune responses, blood parameters, susceptibility to bacterial (Aeromonas hydrophila) infection, and macrophage activity in the freshwater air-breathing Asian catfish, Saccobranchus fossilis, during a 28-day exposure were examined by a static bioassay test procedure. At 0.1, 1.0, and 3.2 mg / liter Cr, dose-dependent Cr accumulation in kidney, liver, and spleen was observed at the end of the experiment. Chromium exposure caused a significant change in spleen to body weight ratio. Fish exposed to Cr concentrations had lower antibody titer values, reduced numbers of splenic and kidney plaque-forming cells, and higher counts of splenic lymphocytes but reduced counts of kidney cells when compared with the control group. At 0.1, 1.0, and 3.2 mg /liter Cr, dose-dependent decreases in red blood cell counts, hemoglobin content, and packed cell volume were observed. Differential leukocyte counts revealed that Cr exposure caused a significant decrease in large and small lymphocytes, whereas neutrophils and thrombocytes increased. Effects of Cr exposure to mitogen (Con A) on proliferation of splenic and pronephric lymphocytes suggests a decrease in mitogenic response. The eye-allograft rejection time, as a parameter of cell-mediated immunity, was statistically increased at 1.0 and 3.2 mg/liter Cr. Fish exposed to Cr for 28 days exhibited higher susceptibility to A. hydrophila infection than control fish. The results suggest that Cr exposure reduced the resistance of catfish to bacterial infections. The phagocytic activity of splenic and pronephros macrophages was examined in vitro and found to be significantly decreased.     

α-硫辛酸对氧化损伤大鼠肝细胞及代谢酶影响

目的 探讨α-硫辛酸(α-liplic acid,α-LA)对过氧化氢(H_2O_2)氧化损伤的大鼠肝细胞及糖代谢酶的影响.方法 分别将50,100,200 μmol/Lα-LA作用于大鼠肝细胞24 h后,用H_2O_20.2 moVL损伤1 h,分别检测细胞活力、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力和丙二醛(MDA)、细胞中葡萄糖激酶(GK)、糖原合成酶激酶-3(GSK-3)的含量.结果 α-LA各剂量组GsH-Px活力与SOD活性分别为141.552～208.171和10.852～13.151U/(mg·prot),均高于H_2O_2损伤组(P<0.05).α-LA各剂量组MDA含量为12.064～14.142 nmol/(mg·prot),明显低于H_2O_2损伤组(P<0.05).α-LA各剂量组葡萄糖激酶(GK)含量为0.928～1.020 mg/L,明显高于H_2O_2损伤组(P<0.05),不同剂量α-LA组GSK-3含量与H_2O_2损伤组比较差异无统计学意义(P<0.05).结论 α-LA对H_2O_2所致大鼠肝细胞氧化损伤具有一定的保护作用,且提高葡萄糖激酶含量.     

An evaluation of the effect of eicosapentaenoic acid in the diet on macrophage PGE production and lymphocyte proliferation in a burned guinea pig model

This study was undertaken to determine if dietary eicosapentaenoic acid (EPA) could affect the production of PGE (PGE₂ and/or PGE₃) by splenic macrophages and the mitogen-induced proliferation of splenic lymphocytes.Guinea pigs received a 30% total body surface area burn following installation of gastrostomy feeding tubes. All animals received identical diets except for the lipid component which equalled 10% of total energy. The control diet contained only linoleic acid (LA) as the lipid component. The experimental diets contained increasing amounts of EPA. Fourteen days postburn, the animals were sacrificed and splenic lymphocytes and macrophages were obtained and cultured for lymphocyte proliferation with and without mitogen stimulation and for PGE₂ synthesis in response to bacterial lipopolysaccharide (LPS), respectively.Increasing amounts of EPA in the diets had no statistically significant effect on the total production of PGE (PGE₂ and/or PGE₃) by macrophages stimulated with LPS, however, when 100% EPA was used as the lipid component, the production of PGE₂ was increased. Also, increasing amounts of EPA in the diet did not affect lymphocyte proliferation following stimulation of the cells with various mitogens, although at an EPA:LA ratio of 75:25%, a significant increase in proliferation of unstimulated but not stimulated lymphocytes was observed. However, at a 100:0 ratio of EPA:LA, lymphocyte proliferation was back down to the control level. This study shows that dietary EPA in high concentrations may have some complex interaction with the immune system at least in the animal under the stress of a burn.     

维生素A与铁缺乏对小鼠免疫功能的影响

目的 :　通过建立动物模型 ,观察维生素 A( VA)与铁 ( Fe)缺乏对小鼠免疫功能的影响 ,为在人群中科学而合理地实施 VA与铁的联合干预提供理论依据。方法 :　人工制备缺 VA( - VA)、缺 Fe( - Fe)和缺 VA、Fe( - VA- Fe)三种饲料 ,相对等饲喂养小鼠 5 w,眼窝静脉采血测定全血铁、血红蛋白、血清 VA、血清溶血素及 T淋巴细胞 α-醋酸萘酯酶 ( ANAE)阳性率 ,无菌摘取免疫器官制备脾细胞悬液进行细胞培养 ,测定脾脏抗体生成细胞 ( PFC)数并用颜色反应 ( MTT)法检测 T淋巴细胞增殖功能。结果 :　摄入 - VA- Fe饲料组小鼠血清 VA与全血铁分别为 ( 0 .85±0 .0 1 )μ mol/L和 ( 6.0 6± 1 .43) mmol/L,显著低于对照组和其它实验组 ;特异性细胞免疫指标MTT值与α- ANAE阳性率分别为 ( 0 .36± 0 .0 3) %和 ( 4 0 .37± 8.2 2 ) % ,均显著低于对照组和低VA组 ;体液免疫指标 PFC亦以 - VA- Fe组最低 ,为 1 877.5 0± 2 73.37( /5× 1 0 6脾细胞 )。结论 :　 VA与 Fe同时缺乏对小鼠细胞免疫和体液免疫功能均有不同程度损伤 ,这种损伤较单独缺乏时广泛而严重。     

Low-level exposure to methylmercury modifies muscarinic cholinergic receptor binding characteristics in rat brain and lymphocytes: physiologic implications and new opportunities in biologic monitoring

Methylmercury (MeHg) affects several parameters of cholinergic function. These alterations are thought to play a role in MeHg neurotoxicity. In vitro experiments have indicated that MeHg acts as a strong competitive inhibitor of radioligand binding to muscarinic cholinergic receptors (mAChRs) in rat brain. Furthermore, rat brain mAChRs share several pharmacologic characteristics of similar receptors present on lymphocytes. Using the muscarinic antagonist [(3)H]quinuclidinyl benzilate (QNB) to label receptors, we investigated the in vivo interactions of MeHg with rat brain mAChRs. We also investigated whether MeHg-induced central mAChR changes are reflected by similar alterations in splenic lymphocytes. Exposure to low doses of MeHg--0.5 or 2 mg/kg/day in drinking water--for 16 days significantly increased (20-44% of control) mAChRs density (B(max)) in the hippocampus and cerebellum without affecting receptor affinity (K(d)). The effect of MeHg did not occur immediately; it was not apparent until 2 weeks after the termination of treatment. No significant changes in [(3)H]QNB binding were observed in the cerebral cortex. In splenic lymphocytes, mAChR density was remarkably increased (95-198% of control) by day 14 of MeHg exposure and remained enhanced 14 days after the cessation of treatment. These results suggest up-regulation of mAChRs in selected brain regions (hippocampus and cerebellum) after prolonged low-level ingestion of MeHg in rats. These cerebral effects are delayed in onset and are preceded by a marked increase in density of mAChRs on lymphocytes. In chronic MeHg exposure, peripheral lymphocytes may represent a sensitive target for the interaction of MeHg with mAChRs and, therefore, may be predictive indicators of later adaptive response involving cerebral mAChRs. Additionally, the effect of MeHg on lymphocyte mAChRs in vivo indicates that this receptor system should be investigated further as a possible target for MeHg immunotoxicity.     

Propanil exposure induces delayed but sustained abrogation of cell-mediated immunity through direct interference with cytotoxic T-lymphocyte effectors

The postemergent herbicide propanil (PRN ; also known as 3,4-dichloropropionanilide) is used on rice and wheat crops and has well-known immunotoxic effects on various compartments of the immune system, including T-helper lymphocytes, B lymphocytes, and macrophages. It is unclear, however, whether PRN also adversely affects cytotoxic T lymphocytes (CTLs) , the primary (1 degrees ) effectors of cell-mediated immunity. In this study we examined both the direct and indirect effects of PRN exposure on CTL activation and effector cell function to gauge its likely impact on cell-mediated immunity. Initial experiments addressed whether PRN alters the class I major histocompatibility complex (MHC) pathway for antigen processing and presentation by antigen-presenting cells (APCs) , thereby indirectly affecting effector function. These experiments demonstrated that PRN does not impair the activation of CTLs by PRN-treated APCs. Subsequent experiments addressed whether PRN treatment of CTLs directly inhibits their activation and revealed that 1 degrees alloreactive CTLs exposed to PRN are unimpaired in their proliferative response and only marginally inhibited in their lytic activity. Surprisingly, secondary stimulation of these alloreactive CTL effectors, however, even in the absence of further PRN exposure, resulted in complete abrogation of CTL lytic function and a delayed but significant long-term effect on CTL responsiveness. These findings may have important implications for the diagnosis and clinical management of anomalies of cell-mediated immunity resulting from environmental exposure to various herbicides and other pesticides.     

Effects of 0.60 PPM nitrogen dioxide on circulating and bronchoalveolar lavage lymphocyte phenotypes in healthy subjects

Nitrogen dioxide (NO2) is a common oxidant air pollutant. Animal studies have suggested that NO2 exposure causes a decrease in the numbers of some splenic lymphocyte subtypes and impairs lymphocyte-dependent immune responses. To investigate whether ambient levels of NO2 alter circulating and bronchoalveolar lavage fluid (BALF) human lymphocytes, we studied five healthy nonsmoking adult volunteers. In each subject, blood and bronchoalveolar lavage fluid was obtained and then, more than 2 weeks later, volunteers were exposured to 0.60 ppm NO2 for 2 hr with intermittent light to moderate exercise on 4 separate days within a 6-day period. We measured standard tests of pulmonary function (airway resistance, thoracic gas volume, maximal expiratory flow) and had the subjects rate the severity of respiratory symptoms before and after each NO2 exposure. Circulating and BALF lymphocytes were labeled with fluorochrome-conjugated monoclonal antibodies to human lymphocyte antigens and a flow cytometer was used to count lymphocyte subtypes. Neither any single day's exposure nor all four exposures caused a change in symptoms or in the results of tests of pulmonary function. The total number of circulating lymphocytes obtained after NO2 exposure was slightly greater than at baseline (1792 +/- 544 vs 1598 +/- 549 cells/mm3 at baseline; P = not significant) but the proportions of lymphocyte subtypes did not differ. In the BALF obtained after NO2 exposure and in the baseline state, the total number of lymphocytes and the percentages of T cells (CD 3), B cells (CD 20), T cytotoxic-suppressor cells (CD 8), T helper-inducer cells (CD 4), and large granular lymphocytes (CD 57) also did not differ after NO2 exposure. A slightly but significantly greater proportion of natural killer cells (CD 16) was found in the BALF obtained after NO2 exposure (7.2 +/- 3.1 vs 4.2 +/- 2.4% of total lymphocytes). We conclude that repeated exposures of healthy nonsmoking adults to 0.60 ppm NO2 are not associated with clinically significant symptoms, changes in airway caliber, or alterations in circulating and BALF lymphocyte subtypes. We suggest that brief, daily exposures to NO2 at levels higher than those achieved in urban atmosphere are unlikely to provoke acute respiratory impairment in healthy, nonsmoking adults.     

6种多糖对小鼠免疫细胞活性作用的比较研究

目的探讨香菇多糖等6种多糖(LPS)对小鼠免疫细胞活性的作用,并比较其免疫调节作用的途径和强度。方法6种多糖体外作用于小鼠免疫细胞,MTT法测脾淋巴细胞增殖活性,ELISA法测LPS诱导的脾淋巴细胞分泌IgG水平,吞噬中性红法测腹腔巨噬细胞吞噬功能,乳酸脱氢酶测定法测脾NK细胞活性。结果协同ConA促进脾淋巴细胞增殖作用强弱依次是香菇多糖、灵芝多糖、黄芪多糖、人参多糖、海带多糖和地衣多糖(P<0.05);协同LPS促进脾淋巴细胞增殖作用依次是灵芝多糖、香菇多糖、地衣多糖、黄芪多糖和人参多糖(P<0.05);促进脾淋巴细胞分泌IgG的依次是黄芪多糖、灵芝多糖、人参多糖、地衣多糖和>香菇多糖(P<0.05);增强腹腔巨噬细胞吞噬活性的依次是黄芪多糖、地衣多糖、香菇多糖、海带多糖、灵芝多糖和人参多糖(P<0.05);增强脾NK细胞活性的依次是黄芪多糖、地衣多糖、海带多糖、香菇多糖和灵芝多糖(P<0.05)。结论6种多糖作用的机制和效果各不相同,香菇多糖、灵芝多糖、地衣多糖和黄芪多糖分别在增强细胞免疫、体液免疫和非特异免疫的某一功能上效果显著,可以适宜的剂量比例组合成复合多糖。