八珍汤对TGF-β1抑制的T淋巴细胞增殖及其活化影响

目的:研究八珍汤对TGF-β1抑制下人T淋巴细胞的增殖及活化的影响.方法:以正常人外周血来源的T淋巴细胞为研究对象, 设对照组、 PHA组、 PHA+八珍汤组、 PHA+TGF-β1组、 PHA+TGF-β1组+八珍汤组.以MTT法检测八珍汤对TGF-β1抑制的T淋巴细胞增殖的影响;流式细胞术(FCM)检测八珍汤对TGF-β1抑制的T淋巴细胞活化的影响及对CD4+CD25+调节性T淋巴细胞的数量的影响;ELISA法检测八珍汤对TGF-β1抑制的T淋巴细胞分泌IFN-γ、 IL-2的影响.结果:八珍汤可以使TGF-β1抑制的T淋巴细胞的增殖率回升(P<0.01), 但仍低于对照组(P<0.01), 并随TGF-β1作用时间的延长, 恢复难度增加.八珍汤可以使T淋巴细胞活化率增加, TGF-β1+八珍汤组与TGF-β1组的活化标志CD69表达有统计学差异(P<0.01);八珍汤能使CD4+CD25+调节性T淋巴细胞的比例降低(P<0.01);能使T淋巴细胞分泌IFN-γ、 IL-2的能力恢复(P<0.01), 但都未能恢复到TGF-β1抑制前的水平, 明显低于PHA组水平(P<0.01).结论:八珍汤对TGF-β1抑制的T淋巴细胞增殖率、 T淋巴细胞的活化、 CD4+CD25+调节性T细胞比例、 IFN-γ、 IL-2的分泌水平都有一定的恢复作用.     

TGF-β1对单核细胞来源的树突状细胞表型和功能的影响

目的:研究 TGF-β1对树突状细胞(DC)的分化、成熟及功能影响.方法:应用100万U/L粒-巨噬细胞集落刺激因子(GM-CSF)和白细胞介素-4(IL-4)7 d诱导单核细胞分化为不成熟DC,加入终浓度20万U/L的肿瘤坏死因子-α(TNF-α)48 h后获得成熟DC的体外模型,将TGF-β1加入该模型中,用流式细胞术分别检测DC分化,成熟阶段细胞表型的变化,应用ELISA检测DC IL-12的分泌水平,应用MTT法检测DC刺激同种异体T细胞增殖的能力.结果:TGF-β1对不成熟DC的特征性分子 CD1a的表达无明显影响,但在诱导DC的成熟阶段,TGF-β1明显抑制CD40、CD86及CD83上调.此外,TGF-β1显著减少DC IL-12的分泌,显著抑制DC刺激同种异体T 细胞增殖的能力.结论:DC是TGF-β1免疫抑制活性的靶细胞.TGF-β1不影响DC的分化,但抑制DC的成熟和细胞因子的分泌,降低DC刺激同种异体反应T细胞增殖的能力.     

TGF-β1诱导的调节性T细胞体内输注延长小鼠皮肤移植物存活

目的 利用TGF-β1体外诱导naYve T细胞分化为凋节性T细胞(Treg),通过体内输注延长小鼠皮肤移植物存活时间,并研究其相关机制. 方法 根据诱导条件不同分为3组:对照组(加入IL-2培养的C57BL/6小鼠T细胞)、MLR组(即混合淋巴细胞反应组,经同种抗原刺激活化的C57BL/6小鼠T细胞)和TGF-β组(经同种抗原刺激活化的C57BL/6小鼠T细胞,同时加入5.0ng/ml TGF-β1诱导).利用FACS检测CD4+CD25+T细胞比例,并用RT-PCR检测Foxp3的表达水平.建立小鼠皮肤移植模型,并于第0、l、2和3天输注上述细胞,观察皮肤移植物存活时间.术后第9天,取部分受鼠行移植物病理检测,用FACS检测脾脏中THl、TH2和CD4+CD25+Treg比例,并用Alamar Blue法检测淋巴细胞增殖能力. 结果 TGF-β组中CD4+CD25+T细胞比例高于对照组和MLR组(P<0.05),且其高表达Foxp3.将培养的细胞输注给受鼠后发现,输注MLR组细胞的受鼠其移植物平均存活时间(mean survival time,MST)为(9.4±1.3)d,低于对照组(P<0.05);而输注TGF-13组细胞小鼠MST为(22.8±1.9)d,较对照组和MLR组明显延长(P<0.05).病理检测亦显示TGF-β组受鼠移植物结构完整,无明显淋巴细胞浸润.FACS结果显示TGF-β组小鼠体内TH1细胞(CD4+TIM-3+)比例低于对照组和MLR组(P0.05),但低于对照组(P<0.05);而且TGF-β组中CD4+CD25+Treg比例明显高于对照组和MLR组(P<0.05).用Alamar Blue法检测受鼠外周淋巴细胞增殖活性显示,TGF-β组受鼠淋巴细胞增殖能力被明显抑制,低于对照组(P<0.05). 结论 TGF-β1可诱导T细胞分化为具有抑制能力的Treg将诱导后的细胞进行过继输注可使小鼠体内CD4+CD25+Treg比例升高,同时抑制TH1和TH2细胞分化扩增,并使得外周淋巴细胞增殖能力减弱,从而延长小鼠皮肤移植物存活时间.     

肺癌小鼠MDSC和T细胞变化

目的:探讨肺癌小鼠CD4+T细胞、CD8+T细胞和骨髓源性抑制细胞(MDSC)的比例和数量变化。方法:采用LLC细胞皮下接种制备小鼠肺癌肿瘤模型,流式细胞仪检测肿瘤小鼠骨髓、脾脏、淋巴结内CD4+T细胞、CD8+T细胞和MDSC的数量变化。结果:与正常对照小鼠相比,肿瘤小鼠脾脏、淋巴结内CD4+T细胞、CD8+T细胞的比例和数量显著降低,骨髓CD4+T细胞变化不明显,但CD8+T细胞显著减少。MDSC在肿瘤小鼠骨髓、脾脏和淋巴结内的比例和数量则显著增加。结论:肺癌小鼠T细胞数量降低而MDSC细胞数量增加,诱导对肿瘤细胞的免疫耐受。     

慢病毒介导RNA抑制黑素瘤细胞Foxp3蛋白表达

目的:利用RNA干扰(RNAi)技术在体外干扰小鼠B16黑素瘤细胞Foxp3基因表达,探讨RNA干扰用于黑素瘤治疗的可行性。方法:针对Foxp3基因设计小干扰RNA(siR-NA),构建起短发夹状RNA(shRNA)慢病毒表达载体,并转染小鼠B16细胞,在体外诱导RNA干扰。分别采用Westernblot和RT-PCR检测Foxp3基因的表达情况;ELISA检测TGF-β1、TGF-β2和IL-10等细胞因子的变化;将干扰后的小鼠B16细胞与CD4+CD25-T淋巴细胞共培养,CCK8法检测CD4+CD25-T淋巴细胞增殖能力。结果:通过Foxp3 shRNA的转染,可实现对B16细胞Foxp3表达的沉默,可下调肿瘤细胞对CD4+CD25-T淋巴细胞增殖抑制的能力,并且下调TGF-β1、TGF-β2和IL-10等细胞因子的表达,尤其是TGF-β2的表达。结论:RNA干扰可抑制小鼠黑素瘤细胞靶基因Foxp3的表达及细胞增殖,并对CD4+CD25-T淋巴细胞增殖抑制的能力减弱,同时减弱抑制性细胞因子的分泌,为黑素瘤的基因治疗提供了新思路。     

全葡聚糖颗粒对DC诱导CD4+T细胞向Th17细胞分化的影响

目的研究全葡聚糖颗粒(whole glucan particle,WGP)对DC诱导CD4~+T细胞向Th17细胞分化的影响。方法采用重组小鼠FMS样酪氨酸激酶3配体(Flt3L)法诱导C57BL/6小鼠骨髓来源树突状细胞(BMDC)。用MACS磁珠分选法对OT-Ⅱ小鼠的脾脏和淋巴结中CD4~+T细胞进行纯化,加入特异性抗原卵清蛋白(OVA),与DC共培养。实验分组为:CON组、WGP组、TGP-β组、WGP+TGF-β组,培养5 d后,利用流式细胞术(FCM)检测各组中CD4~+T细胞增殖和Th17细胞变化情况,ELISA检测各组细胞上清液中IL-17A的含量,Q-PCR检测各组细胞中Th17细胞核转录因子维甲酸孤儿受体-γt(retinoid-related orphan receptor-γt,ROR-γt)mRNA表达水平。结果 TGF-β可以促进DC诱导CD4~+T细胞向Th17分化,而经WGP激发后,T细胞显著下调ROR-γt的转录水平,并减少对IL-17A的分泌。结论 WGP显著抑制TGF-β诱导CD4+T细胞向Th17细胞分化。     

GM-CSF与TGF-β联合处理小鼠供体骨髓细胞诱导特异性免疫耐受

目的:观察用GM-CSF和TGF-β在体外处理供体骨髓细胞(BM)后,输给受体鼠,观察能否诱导受体鼠对供体鼠淋巴细胞的特异性耐受。方法:体外用GM-CSF与TGF-β联合处理供体BM细胞诱导非成熟树突状细胞(iDC),并检测其成熟度。将BALB/c受体鼠随机分为3组,进行不同的预处理:(1)BM预免疫组:经尾静脉输入体外诱导的iDC,1×105细胞/只;(2)脾细胞预免疫组:经尾静脉输入C57BL/6供体鼠脾细胞,1×105/只;(3)阴性对照组:经尾静脉输入同体积的PBS。每组小鼠均需经过2次预免疫,每次间隔1周。第2次处理后1周,所有组的小鼠均接受相同剂量的C57BL/6来源的脾细胞腹腔注射,1×105/只。脾细胞攻击后3d,检测各组小鼠对C57BL/6小鼠脾细胞的同种异体反应水平,检测指标包括:采用单向混合淋巴细胞培养方法检测受体鼠淋巴细胞对供体鼠淋巴细胞的增殖指数;采用双抗体夹心ELISA检测受体鼠血清中IFN-γ和IL-10水平、FCM检测脾脏CD4+CD25highTreg细胞含量、及NK细胞抑制性受体KLRG1的表达、采用乳酸脱氢酶释放法检测NK细胞杀伤功能。结果:经GM-CSF和TGF-β体外处理的供体BM细胞能够抵抗脂多糖(LPS)促成熟的作用;与脾细胞预免疫组相比,经此BM细胞预处理的小鼠,再次遭遇供体小鼠淋巴细胞时,血清IL-10的含量降低(P0.05)、脾脏中CD4+CD25highTreg细胞的比例明显升高、对C57BL/6小鼠淋巴细胞增殖反应减弱(P0.01);NK细胞杀伤率降低。结论:用GM-CSF与TGF-β联合处理供体小鼠BM细胞在一定程度上能够诱导小鼠对供体小鼠脾细胞的免疫耐受,除Treg外,NK细胞可能也参与了诱导免疫耐受。     

双氢青蒿素通过调节TGF-β/Smad通路改善小鼠接触性皮炎北大核心CSCD

目的:探讨双氢青蒿素(DHA)对小鼠接触性皮炎(CHS)的抑制作用及机制。方法:0.5%2,4-二硝基氟苯(DNFB)涂抹小鼠腹部连续2 d致敏,5 d后用0.25%DNFB涂抹左耳发敏,右耳涂抹丙酮和橄榄油混合液作为对照,于致敏前2 d灌胃给予DHA处理。HE染色观察小鼠皮肤组织病理学变化,免疫组化染色观察小鼠耳部皮肤CD4^(+)T、CD8^(+)T细胞浸润情况,测定脾脏指数。ELISA检测血清IL-6、IFN-γ、IL-10、TGF-β和单核细胞趋化蛋白(MCP)-1变化,Western blot检测皮肤Smad2和Smad3磷酸化水平,流式细胞术检测皮肤和脾脏免疫细胞浸润情况。结果:DHA可显著改善CHS小鼠耳朵肿胀、皮肤红斑及脾脏指数(P<0.05)。组织病理学结果显示,DHA处理可明显抑制CHS小鼠皮肤增厚和炎症细胞浸润。流式细胞术结果显示,DHA处理后皮肤和脾脏中浸润的CD4^(+)T细胞、CD8^(+)T细胞、树突状细胞和巨噬细胞显著减少(P<0.05)。ELISA结果显示,相对于模型组,DHA处理组血清IL-6、IFN-γ、TGF-β和MCP-1水平明显降低(P<0.05)。Western blot结果表明DHA处理显著抑制皮肤Smad2和Smad3磷酸化水平(P<0.05)。结论:DHA通过减少免疫细胞浸润和调节TGF-β/Smad信号传导抑制CHS,为治疗CHS提供了新的药物选择和实验依据。     

瘦素对小鼠乳腺癌调节性T细胞的影响

目的探讨瘦素对小鼠乳腺癌调节性T细胞的影响及生物学意义。方法培养4T1乳腺癌细胞株并接种于Balb/c小鼠建立乳腺癌模型,将成瘤小鼠随机分为对照组和实验组,分别用等量生理盐水(normal saline,NS)和瘦素(leptin)处理,监测小鼠肿瘤的生长;流式细胞技术检测各组Balb/c荷瘤小鼠外周血、淋巴结、脾脏中调节性T淋巴细胞的数量及比例变化;ELISA检测各组荷瘤小鼠血清TGF-β1、IL-10含量。结果与NS组比较,实验组肿瘤生长速度随瘦素质量浓度的增加而加快;外周血和脾脏中调节性T细胞比例随瘦素质量浓度的增加而升高(P0.05),淋巴结中调节性T细胞比例变化不明显(P0.05),血清中TGF-β1、IL-10的含量随瘦素质量浓度的增加而升高(P0.05)。结论瘦素通过上调乳腺肿瘤微环境中调节性T细胞的数量比例,分泌抑制因子,抑制机体肿瘤免疫,进而促进小鼠乳腺肿瘤的生长。     

调节性DC分泌的外体诱导免疫耐受功能的体外研究

为了探讨树突状细胞(DC)分泌的外体(Dex)在诱导T细胞免疫耐受中的作用,体外研究采用供体Dex降低同种异体移植排斥的可能性。从正常人外周血单个核细胞中诱导培养未成熟DC(imDC),用TGF-β1联合IL-10诱导调节性DC,LPS诱导DC成熟。采用流式细胞术方法观察TGF-β1和IL-10对DC表型、吞噬功能的影响;采用超速离心和超滤的方法提纯Dex;Western blot方法检测imDC分泌的Dex(imDex)与调节性DC分泌的Dex(rDex)表达的相关分子;通过CCK-8法分析异源iDex和mDex在混合淋巴细胞反应(MLR)中的生物学功能,并比较rDex与iDex诱导免疫耐受的能力。结果显示,TGF-β1和IL-10可下调DC表面的共刺激分子CD80、CD83、CD86的表达,并诱导调节性DC分泌更多的rDex;异源的mDC分泌的Dex(mDex)在mDC存在时增强MLR,而异源的imDex在imDC存在时一定程度上抑制MLR,rDex诱导的抑制T细胞增殖作用显著强于iDex;rDex表达更多的FasL,提示TGF-β1和IL-10诱导的调节性DC分泌的rDex在免疫耐受中发挥重要作用,有望应用于同种异体移植抗免疫排斥。     

香加皮杠柳苷对荷瘤小鼠的免疫调节作用

目的:研究香加皮杠柳苷(CPP)对荷瘤小鼠的免疫调节作用及其作用机制.方法:建立BALB/c小鼠H22皮下移植瘤,观察低、中、高剂量CPP(0.25、0.50、1.00 mg/kg)对荷瘤小鼠免疫器官的影响,应用流式细胞术检测各组小鼠脾T淋巴细胞亚群的分布,应用MTT法检测ConA诱导的小鼠脾淋巴细胞增殖活性,用ELISA试剂盒测定各组荷瘤小鼠血清中细胞因子TNF-α、IL-2和IL-12的含量.结果:对照组荷瘤小鼠的胸腺指数及脾脏指数均明显低于未荷瘤正常小鼠(P<0.05),而CPP组荷瘤小鼠的胸腺指数及脾脏指数较对照组明显增高,甚至高于正常对照组(P<0.05).CPP对荷瘤小鼠体内CD8+T细胞数量无影响,但可明显上调CD3+、CD4+T细胞数及CD4+/CD8+比值,其中CD3+、CD4+细胞百分率与正常小鼠无差别(P>0.05),CD4+/CD8+比值高于正常小鼠(P<0.05).CPP可明显增强ConA诱导的荷瘤小鼠脾淋巴细胞的增殖能力,SI甚至超过正常对照组(P<0.05).不同剂量CPP组小鼠血清中TNF-α、IL-2和IL-12水平均较对照组明显增高(P<0.05),并随剂量增加呈升高趋势,至接近或超过正常小鼠水平.结论:CPP可保护荷瘤小鼠的免疫器官不受损害,并可明显提高CD4+T细胞百分率和CD4+/CD8+比值,增强荷瘤小鼠T细胞增殖能力,促进细胞因子TNF-α、IL-2和IL-12的产生,表明CPP具有显著的免疫增强作用.     

Subsets, expansion and activation of myeloid-derived suppressor cells

Tumor cells and microorganisms manipulate the immune system to minimize any counter response in order to survive. Myeloid-derived suppressor cells (MDSC) in the mouse represent activated Gr-1⁺ CD11b⁺ myeloid precursor cells. Activation may occur through endogenous or exogenous factors leading to the suppression of immune responses. Under steady state conditions the same precursors differentiate into dendritic cells, macrophages and neutrophils. Their linkage to tumor progression and several suppression mechanisms employing the arginine metabolism are well documented, but knowledge of their role in chronic infections, autoimmune diseases and graft-versus-host reactions is just emerging. Several factors have been described to promote MDSC expansion and activation in bone marrow, spleen and tumor sites. New evidence suggests that the Gr-1 antibody itself may differentially trigger myelopoiesis under steady state conditions or induce apoptosis in inflammatory situations after binding to a common epitope expressed on Ly-6C and Ly-6G molecules, respectively. Moreover, two subsets of neutrophil- and monocyte-related MDSC have been described in tumor-bearing and healthy mice. In the present review, we summarize some early work leading to recent findings on these two MDSC subsets, the factors supporting MDSC expansion and activation, as well as novel insights on Gr-1 antibody functions.     

GBEE对荷瘤小鼠IL-2、IL-12、TNF-α及TGF-α水平的影响

目的:研究银杏外种皮提取物(GBEE)的抗肿瘤作用及其对荷瘤小鼠免疫功能的影响。方法:采用ICR小鼠,建立S180移植瘤模型,GBEE连续灌胃16天,观察荷瘤小鼠移植瘤抑制率;体外培养荷瘤小鼠脾脏细胞,应用LPS诱生IL-12,应用ConA诱生IL-2;采用双抗体夹心ABC-ELISA法测定IL-12及荷瘤小鼠血清TNF-α含量;采用MTT法检测IL-2活性;采用放射免疫分析法测定荷瘤小鼠血清TGF-α的含量。结果:GBEE可明显抑制小鼠S180移植瘤的生长,其中200 mg/(kg.d)剂量组抑瘤率达38.36%;GBEE可提高荷瘤小鼠血清TNF-α含量,促进脾淋巴细胞IL-12的形成,增强脾脏T淋巴细胞IL-2活性,降低荷瘤小鼠血清TGF-α水平。结论:GBEE可抑制瘤细胞分泌TGF-α,具有显著抗肿瘤作用;可促进细胞因子IL-2、IL-12和TNF-α的生成,具有增强荷瘤机体免疫功能的作用。GBEE的免疫增强效应可能是其发挥抗肿瘤作用的重要途径之一。     

B7-H1 on myeloid-derived suppressor cells in immune suppression by a mouse model of ovarian cancer

Myeloid-derived suppressor cells (MDSCs) accumulate in tumor-bearing hosts and are associated with immune suppression. Here, we described high level of expression of B7-H1 (CD274), PD-1 (CD279) and CTLA4 (CD152) by Gr-1⁺CD11b⁺ MDSCs obtained from both ascites and spleens of mice bearing the 1D8 ovarian carcinoma, whereas B7-DC (CD273), CD40 and CD86 were absent. In contrast, B7-H1, PD-1 and CTLA-4 expression was not detected on Gr-1⁺CD11b⁺ cells from naive mice. Expression of B7-H1 by Gr-1⁺CD11b⁺ cells from naive mice could be induced by co-culture with 1D8 ovarian carcinoma cells. Gr-1⁺CD11b⁺ cells derived from 1D8 tumor-bearing mice markedly suppressed antigen-specific immune responses, whereas Gr-1⁺CD11b⁺ cells from naive mice did not. siRNA-mediated knockdown of B7-H1 in Gr-1⁺CD11b⁺ cells of 1D8 tumor-bearing mice alleviated suppression of antigen-specific immune responses. Suppression of antigen-specific immune responses via B7-H1 on Gr-1⁺CD11b⁺ myeloid cells was mediated by CD4⁺CD25⁺ Foxp3⁺ T regulatory cells and required PD-1. Antibody blockade of either B7-H1 or PD-1 retarded the growth of 1D8 tumor in mice. This suggests that expression of B7-H1 on Gr-1⁺CD11b⁺ myeloid cells triggered by the 1D8 mouse model of ovarian carcinoma suppresses antigen-specific immunity via interaction with PD-1 on CD4⁺CD25⁺ Foxp3⁺ regulatory T cells.     

Chronic exposure to superantigen induces regulatory CD4(+) T cells with IL-10-mediated suppressive activity

The repeated injection of bacterial superantigens (SAg), such as staphylococcus enterotoxin (SE) A or B, has been shown in mice to induce a state of unresponsiveness characterized by the lack of secretion of Th1 lymphokines, such as IL-2 and IFN-gamma, following subsequent SAg challenge. We made the observation, in vivo as well as in vitro, that unresponsiveness to SAg could be transferred from SEA- to SEB-reactive T cells (and reversibly from SEB- to SEA-specific T cells) in C57BL/6 mice but not in BALB/c mice. Since C57BL/6 mice, unlike BALB/c mice, possess TCR V(beta)3+ and V(beta)11+ T cells able to react with both SEA and SEB, we hypothesized that SAg-unresponsive V(beta)3(+) and V(beta)11+ T cells could mediate linked suppression of other SAg-reactive T cells. To analyze further this possibility, spleen cells from BALB/c mice made unresponsive to SEB were tested for their capacity to suppress the response of normal BALB/c cells to SEB. The production of both IFN-gamma and IL-2 following SEB stimulation was greatly impaired in co-cultures containing CD4(+) T cells, but not CD8(+) T cells, isolated from unresponsive animals. In vivo, the production of both IFN-gamma and IL-2 responses to SEB was dramatically reduced in animals adoptively transferred with unresponsive spleen cells. This suppression was abrogated in recipients injected with neutralizing anti-IL-10 antibodies. Moreover, in animals made unresponsive to SEB, SAg-reactive CD4(+) T cells were found to express high levels of CTLA-4, a molecule recently described to play an essential role in the suppressive function of regulatory T cells. Taken together these results demonstrate that the repetitive injection of SAg induces the differentiation of regulatory CD4(+) T cells capable of suppressing SAg-reactive naive T cells.     

组蛋白去乙酰化酶抑制剂TSA对小鼠胶原诱导性关节炎的治疗作用

目的 研究组蛋白去乙酰酶化抑制剂制滴菌素A(TSA)对小鼠胶原诱导性关节炎的作用,初步探讨其作用机制.方法 将雄性DBA/1小鼠随机分为胶原诱导性关节炎(CIA)模型组、预防性给药组、治疗性给药组、正常组.免疫后第35天处死小鼠,检测小鼠足爪炎症的肿胀度,病理切片观察炎症变化,MTT法检测脾淋巴细胞对胶原的增殖反应,实时荧光定量PCR检测TSA对小鼠脾细胞IFN-γ、IL-4 mRNA表达的影响,ELISA检测IFN-γ、IL-4的含量.结果 CIA模型组关节炎评分、对CⅡ的增殖反应、IFN-γ水平均高于正常对照组;给药组关节炎评分、对CⅡ的增殖反应低于CIA模型组;给药组IFN-γ水平低于CIA组,但IL-4水平高于CIA组.结论 TSA对CIA具有抑制作用,其可能机制是抑制T细胞的活化、增殖,调节Th1/Th2的失衡状态.     

Cannabinoid receptor activation leads to massive mobilization of myeloid-derived suppressor cells with potent immunosuppressive properties

Cannabinoid receptor activation by agents such as Δ(9)-tetrahydrocannabinol (THC) is known to trigger immune suppression. Here, we show that administration of THC in mice leads to rapid and massive expansion of CD11b(+)Gr-1(+) myeloid-derived suppressor cells (MDSC) expressing functional arginase and exhibiting potent immunosuppressive properties both in vitro and in vivo. The induction of MDSC by THC was associated with a significant increase in granulocyte CSF. Moreover, administration of anti-granulocyte CSF Ab inhibited the induction of MDSC by THC. THC was able to induce MDSC in TLR4 mutant C3H and C57BL10/ScN mice and hence acted independently of TLR4. Accumulation of MDSC in the periphery with a corresponding decrease in the proportion of CD11b(+)Gr-1(+) cells in the bone marrow, as well as in vivo BrdU labeling and cell-cycle analysis, showed that THC induced mobilization of these cells from bone marrow and their expansion in the periphery. Use of selective antagonists SR141716A and SR144528 against cannabinoid receptors 1 and 2, respectively, as well as receptor-deficient mice showed that induction of MDSC was mediated through activation of both cannabinoid receptors 1 and 2. These studies demonstrate that cannabinoid receptor signaling may play a crucial role in immune regulation via the induction of MDSC.     

Effects of boar seminal immunosuppressive fraction on production of cytokines by Concanavalin A-stimulated spleen cells and on proliferation of B lymphoma cell lines

PROBLEM: The immunosuppressive fraction (ISF) of boar seminal vesicle fluid has recently been demonstrated to inhibit mitogen-stimulated proliferation of lymphocytes and antibody response to corpuscular and soluble antigens. The effects of ISF on in vitro and in vivo production of cytokines as well as its possible inhibitory effect on proliferation of B lymphoma cells remain to be elucidated. METHODS: The effect of ISF on proliferation of normal mouse spleen cells stimulated by Concanavalin A (Con A) and on mouse B lymphoma cells was measured by 3H-thymidine incorporation. Cytokines were determined in the supernatants of mouse spleen cells stimulated with Con A in the presence or absence of ISF by enzyme-linked immunosorbent assay (ELISA). In vivo cytokine production in the sera samples of mice treated with ISF and immunized with keyhole limpet hemocyanin (KLH) was followed by ELISA, too. RESULTS: We confirmed the inhibitory effect of ISF on Con A-stimulated lymphocyte proliferation. ISF affected cytokine production in the Con A-stimulated spleen cells: production of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) was lowered, but production of IL-4, IL-6, and IL-10 was enhanced. Similarly, in the sera samples of mice immunized with keyhole limpet hemocyanin (KLH), IL-2 and IFN-gamma levels were decreased by ISF. ISF inhibited proliferation of Ag 8 and X 63-IL-2 B lymphoma cells as well. CONCLUSIONS: ISF inhibited production of T helper1 (Th1) cytokines (IL-2 and IFN-gamma) and enhanced production of Th2 cytokines (IL-4, IL-6, and IL-10). ISF seems to shift the Th1/Th2 pattern in favor of Th2. ISF exhibited an antiproliferative activity on mouse B lymphoma cells.     

IL-2预孵育影响G-CSF动员的小鼠脾淋巴细胞增殖及极化观察

目的 探讨IL-2预孵育对粒细胞集落刺激因子(G-CSF)动员后的小鼠脾淋巴细胞功能的影响,从而为减轻异基因造血干细胞移植时急性移植物抗宿主病(GVHD)的发生提供一种新途径.方法 IL-2(50 U/ml)预孵育rhG-CSF(每天0.25 μg/g)体内动员的C57BL/6N小鼠脾细胞和na(i)ve CD4+T细胞6 h,然后在体外以BALB/c小鼠异基因抗原分别对其进行刺激,测定动员后的C57BL/6N小鼠脾细胞和na(i)ve CD4+T细胞的增殖能力以及上清液IL-4、IFN-γ的浓度,实验分为G-CSF+IL-2组、G-CSF组、IL-2组和对照组.结果 G-CSF+IL-2组较列照组A值降低(P＜0.01);G-CSF+IL-2组IL-4水平高于对照组(P＜0.01),而IFN-γ水平低于对照组(P＜0.01).结论 rhG-CSF动员的C57BL/6N小鼠脾细胞和na(i)ve CD4+T细胞经IL-2预孵育后对同种异基因抗原免疫增殖能力明显减弱并向Th2方向分化,两者合用对诱导T淋巴细胞免疫耐受有协同效应.

Abstract：

Objective To explore the influence of IL-2 pretreatment on splenic lymphocyte following mobilization with G-CSF, which may provide a new approach to attenuate acute graft-versus-host disease (GVHD). Methods Splenic cells and na(i)ve CD4+T cells from C57BL/6N mice receiving G-CSF-mobilized were pretreated with IL-2(50 U/ml) , and cocultured with the allogeneic antigens from BALB/c mice. The proliferation responses and the polarization of T cells were determined. C57BL/6N mice were randomly divided into 4 groups: G-CSF + IL-2 group, G-CSF group, IL-2 group , control group. Results Compared with the control group, IL-4 increased obviously while IFN-γ decreased significantly in the group of G-CSF + IL-2. The proliferation responses were also suppressed in vitro. Conclusion The proliferation responses of splenic cells and naive CD4 + T cells from C57BI/6N mice receiving G-CSF-mobilized to the allogeneic antigens were significantly abrogated by the pretreatment with IL-2, T cells were polarized toward the production of type-2 cytokines. The combination of G-CSF and IL-2 is potentially synergetic in the induction of T lymphocyte immune tolerance.     

Natural Killer Cell Activity, Lymphocyte Proliferation, and Cytokine Profile in Tumor-Bearing Mice Treated with MAPA, a Magnesium Aggregated Polymer from Aspergillus oryzae

The present study examined the effects of MAPA, an antitumor aggregated polymer of protein magnesium ammonium phospholinoleate-palmitoleate anhydride, isolated from Aspergillus oryzae, on concanavalin A (Con A)-induced spleen cell proliferation, cytokine production and on natural killer (NK) cell activity in Ehrlich ascites tumor-bearing mice. The Ehrlich ascites tumor (EAT) growth led to diminished mitogen-induced expansion of spleen cell populations and total NK activity. This was accompanied by striking spleen enlargement, with a marked increase in total cell counts. Moreover, a substantial enhancement in IL-10 levels, paralleled by a significant decrease in IL-2 was observed, while production of IL-4 and interferon-γ (IFN-γ) was not altered. Treatment of mice with 5 mg/kg MAPA for 7 days promoted spleen cell proliferation, IL-2 production and NK cell activity regardless of tumor outgrowth. In addition, MAPA treatment markedly enhanced IFN-γ levels and reduced IL-10 production relative to EAT mice. A 35% reduction in splenomegaly with normal number of nucleated cells was also found. Altogether, our results suggest that MAPA directly and/or indirectly modulates immune cell activity, and probably disengages tumor-induced suppression of these responses. Clearly, MAPA has an impact and may delay tumor outgrowth through immunotherapeutic mechanisms.