附子多糖与阿霉素长循环热敏脂质体的抗肿瘤作用及其机制探讨

目的:观察附子多糖(MPS)与阿霉素(ADM)长循环热敏脂质体(ALTSL)联合靶向治疗荷肝癌H22小鼠的作用,并探讨其抗肿瘤作用机制。方法:以荷瘤小鼠的瘤重为指标,观察药物的抗肿瘤活性。以荷瘤小鼠的存活天数计算生命延长率。以乳酸脱氢酶释放法检测NK细胞的杀伤活性。以MTT比色法检测淋巴细胞的转化率。以流式细胞术检测肿瘤细胞的凋亡及p53、Fas、FasL和caspase-3的表达。用RT-PCR法测定IL-2mRNA及IL-12mRNA的表达。制作病理切片观察肿瘤、心、肝、肾脏的组织学变化,探讨抗肿瘤机制。结果:MPS ALTSL联合治疗对肿瘤的抑制作用比单一ALTSL靶向治疗更为显著,抑瘤率达80.4%,并可显著延长荷瘤小鼠的存活时间(P<0.01)。与对照组和ADM组比较,ALTSL可使NK细胞的杀伤活性显著增加,而MPS ALTSL则可使NK细胞的杀伤活性和淋巴细胞转化率进一步提高(P<0.01)。应用ALTSL可使脾细胞中IL-2mRNA和IL-12mRNA的表达明显增高;而MPS ALTSL则可使他们的表达进一步增强。病理切片的结果显示,热敏脂质体配合肿瘤局部加热,可使肿瘤细胞凝固坏死。联合应用MPS,可见肿瘤组织中出现大量的淋巴细胞浸润。结论:ALTSL能提高化疗药物ADM的抗肿瘤效果,并降低其心肺毒性,保护机体的免疫功能。MPS ALTSL能进一步诱导肿瘤细胞凋亡,激活并促进T细胞转化和NK细胞的杀伤活性,增强机体的免疫功能,发挥抗肿瘤的协同作用。     

rhIL-2与阿霉素白蛋白磁微球靶向治疗肿瘤的协同作用

目的：观察重组人白细胞介素-2(rhIL-2)瘤内注射和阿霉素白蛋白磁微球(ADM-MAM)联合外磁场联合治疗H22荷瘤小鼠的协同作用，并探讨其抗肿瘤作用机制。方法：以荷瘤小鼠的瘤重为指标，观察药物的抗肿瘤活性。以乳酸脱氢酶释放法测NK细胞的杀伤活性。以MTT比色法测淋巴细胞的转化率。以流式细胞术检测肿瘤细胞的凋亡及p53、Fas和FasL的表达。用RT—PCR法测定IL—2及IL—12的表达。探讨抗肿瘤机制。结果：ADM—MAM靶向治疗与rhIL—2联用，可显著减小荷瘤小鼠的瘤重；提高NK细胞的杀伤活性和脾脏淋巴细胞的转化率；减小肿瘤细胞的增殖指数，上调肿瘤细胞p53、Fas和FasL的表达，以及增加脾脏淋巴细胞上IL—2及IL—12的表达。结论：ADM—MAM联合外磁场，具有显著增强抑瘤的作用。rhIL—2能增强ADM—MAM靶向治疗的抗肿瘤作用，其抗肿瘤协同作用主要是通过促进T细胞增殖，刺激NK细胞增长等提高机体的免疫功能而实现的。     

三取代型钛钨硅酸盐体内抑瘤效应的免疫机制探讨

目的:探讨三取代型钛钨硅酸盐(WT)体内抑瘤效应的免疫机制。方法:建立荷H22肝癌小鼠模型,WT连续灌胃10d,取出肿瘤称重测定抑瘤率。用MTT比色法测定荷H22肝癌小鼠淋巴细胞转化的活性及NK细胞的杀伤活性。通过形态学观察和流式细胞仪检测WT诱导BEL-7402细胞的凋亡。结果:WT可显著抑制荷瘤小鼠肿瘤生长(P<0.05),提高荷瘤小鼠淋巴细胞转化的活性及NK细胞的杀伤活性(P<0.05),并诱导肿瘤细胞发生凋亡。结论:WT的抑瘤作用与机体免疫功能的增强有关。     

中药复方抑瘤饮影响荷S180瘤小鼠免疫功能的动态研究

研究荷S180瘤小鼠灌服中药复方抑瘤饮(简称抑瘤饮)不同时间点脾细胞免疫功能的动态变化,揭示其体内抗瘤的免疫机制。于BALB/c小鼠右腋皮下接种S180细胞,24 h后,抑瘤饮组开始每日灌服抑瘤饮,对照组灌服等量凉开水。分别于灌服第0、10、20、30、40天处死动物,称取体重和瘤重;无菌获取脾细胞,MTT法检测NK细胞杀伤活性、ConA诱导转化及IL-2诱生活性,流式细胞仪检测CD4+细胞和CD8+细胞百分率。结果显示,抑瘤饮对小鼠体内S180移植肿瘤的生长,有明显的渐增性抑制作用;抑瘤饮能够明显逆转S180移植肿瘤对小鼠脾细胞的NK细胞杀伤率、转化指数、IL-2诱生活性、CD4+细胞和CD8+细胞百分率的抑制作用,且逆转作用呈时间依赖性增强。表明抑瘤饮体内能够渐增地上调被S180移植肿瘤抑制的免疫功能,从而发挥抗瘤作用。     

IL-2与眼镜蛇毒协同抗肿瘤作用的实验研究

本文研究了白细胞介素2(IL-2)和眼镜蛇毒对小鼠移植鼠肝癌的抑制作用以及对荷移植窟小鼠NK细胞杀伤活性的影响。结果表明:IL-2或眼镜蛇毒单独使用时,前者能明显增强荷瘤鼠的NK细胞活性,可是抑瘤作用不很明显;后者虽然严重地减弱荷瘤鼠的NK活性,但抑瘤作用反而较前者为强。当两者联合使用时,其抑瘤作用及NK活性则都显著提高(P<0.005)。提示IL-2与眼镜蛇毒具有良好的协同抗小鼠移植鼠肝癌的作用。     

艾灸对荷瘤小鼠免疫功能的增强作用

作者通过观察艾灸大椎穴对荷瘤小鼠脾淋巴细胞转化,NK细胞,LAK细胞活性,IL-2产生水平,探讨艾灸抑瘤效应的免疫学机理。结果显示:艾灸对荷瘤小鼠免疫功能低下或受抑状态,可起到正向免疫调节作用;艾灸治疗组小鼠T淋巴细胞转化,NK、LAK细胞活性;IL-2产生水平较荷瘤对照组明显增高。本研究结果也显示艾灸的治疗作用有选择性的相对的腧穴特异性,艾灸大椎穴组T细胞转化率、NK细胞活性明显高于艾灸非经穴对照组。艾灸抑瘤效应,可能是通过改善荷瘤机体非特异性免疫功能状态,抑制移植性肿瘤在新宿主的早期生长、发展的结果。     

双氢青蒿素通过调控PI3K/AKT通路增强肝癌H22细胞荷瘤小鼠放疗效果

目的:探讨双氢青蒿素(DHA)调控磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(AKT)通路对肝细胞癌H22细胞荷瘤小鼠放疗增效的影响。方法:构建肝癌H22细胞荷瘤小鼠模型,实验分为模型组、单放疗组、5-氟尿嘧啶(5-FU)组和低、中、高剂量DHA组,每组8只,按照分组进行给药和放疗治疗。隔天测量各组荷瘤小鼠体重和瘤体积,给药结束后鼠尾取血后立刻脱颈处死小鼠。观察DHA对放疗的增效作用和对肿瘤生长的抑制作用,测定淋巴细胞转化程度和自然杀伤(NK)细胞活性,ELISA法检测小鼠血清白细胞介素2(IL-2)和IL-4水平,Western blot法测定小鼠肿瘤组织中PI3K、AKT和p-AKT蛋白水平。结果:成功构建肝癌H22细胞荷瘤小鼠模型。与模型组相比,单放疗组肿瘤3倍倍增时间(TGT3)显著升高(P0.05),瘤重、淋巴细胞转化程度、NK细胞活性、IL-2和IL-4水平、PI3K表达水平和AKT磷酸化水平均显著降低(P0.05);与单放疗组相比,随着DHA剂量升高,TGT3、增敏系数、抑瘤率、淋巴细胞转化程度、NK细胞活性及IL-2和IL-4水平随之升高(P0.05),PI3K表达水平和AKT磷酸化水平随之降低(P0.05)。结论:DHA可能通过抑制PI3K/AKT信号通路活性,提高荷瘤小鼠免疫能力,从而增强放疗效果。     

树突状细胞激活的肿瘤浸润淋巴细胞对荷瘤小鼠免疫功能影响的研究

目的:探讨H22细胞全细胞性抗原致敏的DC激活的TIL体外抗小鼠肝癌活性;并将H22细胞全细胞性抗原致敏的DC激活的TIL(H22-DC-TIL)过继免疫荷瘤小鼠,研究其对荷瘤小鼠免疫功能的影响。方法:从小鼠四肢长骨骨髓中获取DC,应用粒/巨噬细胞集落刺激因子(GM-CSF)、白介素-4(IL-4)和肿瘤全细胞性抗原致敏DC,然后用DC激活TIL,观察TIL在体外对H22细胞、Hepal-6细胞和B16细胞的杀伤活性;检测应用H22-DC-TIL后荷瘤小鼠的脾淋巴细胞的NK、LAK、CTL活性及血清TNF活性,并与对照组相比较。结果:(1)H22-DC-TIL具有很强的对H22细胞杀伤活性(杀伤率为71.31%±3.11%),明显高于其对Hepal-6和B16细胞的杀伤活性(杀伤率分别为50.11%±3.03%和30.31%±2.89%);也明显高于未经DC激活的TIL、H22-DC-小鼠脾淋巴细胞和未经DC激活的小鼠脾淋巴细胞对H22细胞杀伤活性(杀伤率分别为49.80%±3.21%、48.76%±3.60%和19.23%±2.71%)和对Hepal-6细胞杀伤活性(杀伤率分别为39.40%±3.21%、38.62%±2.87%和18.73%±2.40%)以及对B16细胞杀伤活性(杀伤率分别为26.38%±2.51%、25.82%±2.70%和18.34%±3.01%),同时B16-DC-TIL(TIL来源于H22瘤体)也可诱导相对较低的对B16细胞的特异性细胞杀伤活性。(2)H22-DC-TIL可明显诱导提高荷瘤小鼠脾淋巴细胞NK、LAK和CTL活性(活性分别为30.43%±1.35%、31.40%±1.80%和35.30%±1.20%),并可检测到血清TNF水平明显上升[血清TNF为(40.41±1.85)U/m l],它们均达正常对照组水平,与未经DC激活的TIL组、H22-DC-小鼠脾淋巴细胞组、未经DC激活的小鼠脾淋巴细胞组、生理盐水组分别对应比较,差异均有显著性(P<0.01)。结论:(1)H22-DC-TIL可产生很强的体外针对H22细胞的特异性杀伤活性。(2)H22-DC-TIL可明显诱导提高荷瘤小鼠特异性抗肿瘤免疫反应。     

IL-21基因治疗小鼠H22细胞皮下移植肝癌模型的效果评价

用已构建的mIL-21/pcDNA3.1重组质粒对H22细胞建立的小鼠肝癌模型进行基因治疗,观察IL-21对小鼠体内抗肿瘤免疫应答的影响及对小鼠生存的影响。采用BALB/c小鼠左腋皮下注射腹水型肝癌细胞株H22细胞建立小鼠移植肝癌模型,给荷瘤小鼠瘤体内注射mIL-21/pcDNA3.1进行基因治疗,MTT比色法检测IL-21对荷瘤小鼠T细胞增殖水平及NK细胞杀伤活性的影响,观察治疗后荷瘤小鼠生存情况及肿瘤生长情况的改变。病理检测结果显示,成功建立了小鼠移植型肝癌模型,MTT比色法显示基因治疗后小鼠T细胞增殖水平及NK细胞杀伤活性显著升高,荷瘤小鼠肿瘤生长速度减慢,生存期显著延长。IL-21基因治疗肝癌荷瘤小鼠可显著提高荷瘤小鼠体内抗肿瘤免疫应答水平,抑制肿瘤生长,延长荷瘤小鼠生存期。     

小鼠IL-1β在H22细胞的表达及对NK细胞杀伤活性的影响

目的：重组表达小鼠IL-1β全长基因，转染H22肝癌细胞，分析对NK细胞杀伤活性的影响。方法：构建小鼠IL-1β重组表达载体pIRES2-EGFP-mIL-1β，利用jetPEI转染H22肝癌细胞，RT—PCR和激光扫描共聚焦显微镜分析IL-1β重组载体的表达，MTT方法分析转染前后，野生型小鼠脾脏NK细胞对H22细胞杀伤活性的变化。结果：RT—PCR扩增出小鼠IL-1β，长度约843bp。纯化的PCR产物与pIRES2-EGFP同时经Xho I和EcoR I双酶切，在T4连接酶作用下连接，转化大肠杆菌，提取质粒经PCR、限制性酶谱分析（XhoI＋EcoRI）和DNA序列测定后，确认获得重组表达载体pIRES2-EGFP-mIL-1β。将该质粒转染至H22小鼠肝癌细胞中，RT—PCR和荧光观察证实，H22细胞能表达高水平IL-1β重组表达载体，与转染空载体的对照组细胞相比，IL-1β转基因后H22细胞对NK92细胞杀伤抵抗性明显增强，同时野生型小鼠脾脏NK细胞对pIRES2-EGFP-mIL-1β转基因细胞的杀伤活性明显下降，效靶比40：1时下降了约10％。结论：IL-1β能够明显增强H22肝癌细胞对NK细胞杀伤的抵抗性，可能是肝癌细胞借以逃逸天然免疫应答的重要机制。     

阿霉素联合致敏树突状细胞对荷宫颈癌小鼠的治疗作用

 目的：探讨阿霉素(adriamycin,ADM)联合冻融抗原致敏的树突状细胞(dendritic cells,DCs)对荷宫颈癌小鼠的免疫治疗作用。方法：建立小鼠皮下移植瘤模型;应用反复冻融法处理小鼠宫颈癌U14细胞,并致敏小鼠骨髓来源的DCs,制备DCs疫苗;流式细胞术鉴定DCs成熟表型;荷瘤小鼠分为对照组（PBS组）、DCs疫苗组、ADM组和ADM联合DCs疫苗组,进行3个周期的治疗。观察肿瘤大小,第21 d取血,ELISA法检测小鼠血清IL-2、IL-12和IFN-γ含量;处死动物,称肿瘤重量。结果：肿瘤冻融抗原致敏DCs后,可高表达白细胞分化抗原CD11c、CD80和CD86;经3个周期的治疗后,ADM联合DCs疫苗组平均瘤重及平均瘤体积均小于ADM组、DCs疫苗组和对照组(P＜0.05),联合治疗组抑瘤率大于其它3组(P＜0.05),且血清IL-2、IL-12和IFN-γ水平明显升高 (P＜0.05)。结论：ADM联合肿瘤抗原致敏的DCs疫苗可增强动物的抗肿瘤免疫应答,能有效抑制荷宫颈癌小鼠肿瘤的生长。     

Tumor-induced suppression of interferon-gamma production and enhancement of interleukin-10 production by natural killer (NK) cells: paralleled to CD4+ T cells

The predominance of type two cytokines in syngeneic B16 tumor-bearing mice was confirmed by analysing supernatant contents and mRNA copies of IFN-gamma, IL-4, IL-5, IL-10 and IL-13 from splenocytes. The cytokine-producing lymphocytes were then examined by double-staining flowcytometry. Both CD4+IFN-gamma+ T cells and DX5+IFN-gamma+ NK cells from spleen significantly declined, interestingly, the declining degrees of DX5+IFN-gamma+ NK cells were much greater than those of CD4+IFN-gamma+ T cells by the percentage in whole NK or T cells or the absolute amounts per spleen at early tumor stage (day 10) or tumor-advanced stage (day 20). In contrast to DX5+IFN-gamma+ NK cells, DX5+IL-10+ NK cells increased during tumor progression, the increasing degrees of DX5+IL-10+ NK cells were also much greater than those of CD4+IL-10+ T cells by the percentage or the absolute amounts. Though the percentage of DX5+IL-4+ NK cells only increased in early tumor stage (day 10), the increasing degree was also greater than that of CD4+IL-4+ T cells. In 20xfield view under laser confocal microscope, the mean numbers of DX5+IFN-gamma+ NK cells and CD4+IFN-gamma+ T cells dramatically declined after tumor inoculation. These results suggest that cytokines produced by NK cells, at least partly, account for the balance of type one and two cytokines as done by T cells, and in some conditions, that the NK1 or NK2 cells were possibly more sensitive to tumor progression.     

Activity of recombinant human interleukin-15 against tumor recurrence and metastasis in mice

Transplantable experimental tumor models were constructed to study the activities of recombinant human interleukin-15 （rhIL-15） against tumor recurrence and metastasis. The results showed that tumor nodule formation was retarded and tumor growth was inhibited in the subcutaneous tumor model of LA795 lung adenocarcinoma after treatment with rhIL-15, and the survival rate of T739 tumor-bearing mice treated with rhIL-15 was much higher than that of mice treated with either saline or with the same dose of rhIL-2. This indicats that rhIL-15 had better antitumor effect than rhIL-2 at the same dose level. In some rhIL-15 treated mice, the tumor cells inoculated subcutaneously were eradicated and there was no tumor formation even 138 days after tumor cell inoculation. The tumor-free mice were rechallenged with live tumor cells and no tumor reoccurred in the following two months in all of these mice, indicating that long-lasting antitumor systemic immunity developed. It was also shown that tumor recurrence and metastasis were inhibited markedly after treatment with rhIL-15, but not with the same dose of rhIL-2, in both subcutaneously and intravenously disseminated tumor models of LA795 lung adenocarcinoma. Simultaneously, the CTL and NK cell activities of the splenocytes obtained from tumor-bearing mice that had been treated with either rhIL-15 or rhIL-2 were both markedly enhanced. However, the enhancement of CTL and NK cell activities was more significant in rhIL-15 treated mice than that in rhIL-2 treated mice. This suggests that the anti-tumor effect of rhIL-15 in vivo was achieved by enhancing the CTL and NK cell activities in tumor immune response.     

Natural killer cell-dependent immunoglobulin G2a anti-bovine serum albumin (BSA) response elicited by high molecular weight dextran-BSA conjugates associated with dextran-mediated macrophage-natural killer cell interaction

The roles of the interferon-gamma (IFN-gamma) and interleukin-12 (IL-12) produced during natural killer (NK) cell interaction with macrophages (M phi) were investigated as the basis for the induction of immunoglobulin G2a (IgG2a) anti-bovine serum albumin (BSA) responses by high molecular weight dextran conjugated to BSA (HMW-DEX-BSA). BALB/c mice immunized with HMW-DEX-BSA produced significantly higher levels of both IgG1 and IgG2a anti-BSA than did mice immunized with BSA alone. Both IgG1 and IgG2a anti-BSA levels were higher in mice immunized with BSA conjugated to dextran of molecular weight (MW) 5 000 000-40 000 000 compared with dextran of MW 10,000-60,000. The enhancement of anti-BSA IgG2a levels but not of anti-BSA IgG1 levels was inhibited when free BSA was added to the HMW-DEX-BSA conjugate. NK cell depletion during HMW-DEX-BSA immunization of mice resulted in significantly lower anti-BSA IgG2a levels without affecting anti-BSA IgG1 levels. Naive splenocytes or M phi + NK cell co-cultures incubated with HMW-DEX or HMW-DEX-BSA produced higher IFN-gamma levels than splenocytes or co-cultures incubated with BSA alone. HMW-DEX stimulated both IFN-gamma and IL-12 production by M phi + NK cell co-cultures in a dose-dependent manner. DEX-induced IFN-gamma production by NK cells was dependent upon the presence of IL-12, and IL-12 production by M phi was dependent upon the presence of IFN-gamma in these co-cultures. Both M phi and NK cells bound DEX to their surfaces. These data demonstrate that BSA linked to HMW-DEX enhanced both T-helper-1- and T-helper-2-associated antibody responses to BSA. The results also indicate an IL-12-dependent positive feedback interaction between NK cells and M phi that supports a NK cell/IFN-gamma-dependent mechanism for enhancement of anti-BSA IgG2a antibody responses in mice immunized with HMW-DEX-BSA protein conjugates.     

Differential IL-12 responsiveness of T cells but not of NK cells from tumor-bearing mice in IL-12-responsive versus -unresponsive tumor models

While IL-12 administration induces tumor regression through stimulating T cells in tumor-bearing mice, this IL-12 effect is observed in some but not all tumor models. The present study aimed to compare IL-12 responsiveness of T cells from tumor-bearing mice in IL-12-responsive (CSA1M and OV-HM) and -unresponsive (Meth A) tumor models. Tumor regression in IL-12-responsive tumor models required the participation of T cells, but not of NK1.1(+) cells. Because a NK1.1(+) cell population was the major producer of IFN-gamma, comparable levels of IFN-gamma production were induced in IL-12-responsive and -unresponsive tumor-bearing mice. This indicates that the amount of IFN-gamma produced in tumor-bearing individuals does not correlate with the anti-tumor efficacy of IL-12. In contrast, IL-12 responsiveness of T cells differed between the responsive and unresponsive models: purified T cells from CSA1M/OV-HM-bearing or Meth A-bearing mice exhibited high or low IL-12 responsiveness respectively, when evaluated by the amounts of IFN-gamma produced in response to IL-12. T cells from CSA1M- or OV-HM-bearing but not from Meth A-bearing mice exhibited enhanced levels of mRNA for the IL-12 receptor (IL-12R). These results indicate that a fundamental difference exists in IL-12 responsiveness of T cells between IL-12-responsive and -unresponsive tumor models, and that such a difference is associated with the expression of IL-12R on T cells.     

Interleukin 12 is produced in vivo during endotoxemia and stimulates synthesis of gamma interferon.

Gamma interferon (IFN-gamma) is produced in response to circulating lipopolysaccharide (LPS) and contributes to the lethality of endotoxic shock. To address the cellular source of IFN-gamma production in vivo, T cells and B cells were magnetically purified from C57BL/6 mouse spleens 5 h following endotoxin injection. IFN-gamma RNA was abundant in splenic CD4+ and CD8+ T cells and in a T- and B-cell-depleted population of splenocytes containing 34% NK1.1+ natural killer (NK) cells. Because interleukin 12 (IL-12) is a known inducer of IFN-gamma synthesis by cultured T cells and NK cells, we examined whether IL-12 might be involved in IFN-gamma release during endotoxemia. mRNA encoding the p40 subunit of IL-12 increased markedly in the spleens of C57BL/6 mice at 2 h after LPS injection, whereas p35 IL-12 mRNA was constitutively expressed at all times. Bioactive IL-12 (p70 heterodimer) was detected in mouse serum at 2 to 4 h after LPS injection. Similar results were obtained using a p40 subunit-specific enzyme-linked immunosorbent assay. Endotoxin-insensitive C3H/HeJ mice generated threefold less IL-12 p70 and IFN-gamma at these times than endotoxin-sensitive C3H/HeOuJ mice. Pretreatment of mice with polyclonal anti-mouse IL-12 antibody reduced IFN-gamma levels present at 6 h post-LPS nearly sixfold in three separate experiments. These studies support a role for IL-12 as a proximal stimulator of IFN-gamma release during endotoxemia.     

转染IL-21的CD34~+脐血造血干细胞抗裸鼠卵巢癌作用研究

目的 探讨IL-21转染的脐血造血干细胞(CD34~+UBSC·IL-21)对荷卵巢癌裸鼠的治疗作用.方法 从脐血分离CD34~+造血干细胞,体外培养扩增后用于重组体pIRES2-IL-21-EGFP转染.以肿瘤大小、荷瘤鼠生存期判断CD34~+UBSC-IL-21对荷瘤裸鼠的治疗效应.以RT-PCR、免疫荧光、ELISA、Western blot、脾细胞增殖试验及免疫组化法分别鉴定CD34~+UBSC和肿瘤组织中IL-21的表达及活性.裸鼠脾细胞中NK细胞含量及脾细胞的杀伤效应、血清中IFN-γ和TNF-α水平分别用FCM与ELISA检测.结果 pIRES2-IL-21-EGFP成功转染CD34~+UBSC.CD34~+UBSC-IL-21能抑制肿瘤生长,延长荷瘤裸鼠生存期,治疗鼠肿瘤局部能表达IL-21、血清IFN-γ和TNF-α水平升高,NK细胞含量及NK细胞杀伤活性明显增强,与其他组相比,差异有统计学意义(P<0.01).结论 转染IL-21的CD34~+UBSC有良好的抗裸鼠卵巢癌作用,该结果为临床使用UBSC为载体的基因治疗卵巢癌研究奠定了基础.     

Tissue distribution and antitumor effect of liposome-entrapped doxorubicin (adriamycin) in Ehrlich solid tumor-bearing mouse

The usefulness of liposomes (in neutral, positively and negatively charged forms) as a carrier for adriamycin (ADM) was studied by examining the distribution of ADM and related fluorescent compounds in Ehrlich solid tumor-bearing mice. The mice were given free or liposome-entrapped ADM intraperitoneally. The distribution of ADM and related fluorescent compounds between the administration of the free form and liposome-entrapped form was measured by high performance liquid chromatography : The distribution was dependent on the form of the liposomes. The amounts of ADM and its metabolites in the mouse serum 20 min after administration of neutral-liposome-entrapped ADM were 10 times those after the administration of free ADM, 6 times those after the administration of a negatively charged form, and 3.5 times those in the administration of positively charged form. There was no marked difference in the concentrations of these compounds 5 h after administration. The concentration of these compounds in the liver 60 min after administration of each liposome-entrapped form of ADM were in inverse correlation with the concentrations in the serum obtained at 20 min after administration. Total concentrations of ADM and its metabolites in the tumors 20 min after administration of each entrapped form of ADM were 4-5 times that in administration of free ADM after 20 min. There were no marked differences in the concentration of ADM for administration of the various liposome forms. Statistically significant decreases in mean tumor weight were seen in the groups given neutral, positively and negatively charged liposome-entrapped forms compared to corresponding control groups given with free ADM.     

乏氧对人外周血NK细胞NKG2A、NKG2D及CD44表达的影响

目的： 观察乏氧微环境对人外周血自然杀伤细胞(NK)表面自然杀伤细胞2族成员A(NKG2A)、自然杀伤细胞2族成员D(NKG2D)及CD44分子表达的影响,探讨乏氧抑制NK细胞杀伤活性的分子机制。方法: 采用密度梯度离心法分离健康人外周血单个核细胞（PBMC）,贴壁去除单核细胞获得外周血淋巴细胞（PBL）,分别置常氧（21％O2）、乏氧（1％O2）以及有或无人重组白细胞介素2(rhIL-2)（1×106 U/L）刺激条件下培养16 h,流式细胞术（FCM）检测不同 NK细胞亚群 NKG2A、NKG2D以及CD44分子的表达。结果: 常氧条件,人外周血CD3-CD56+NK细胞NKG2A、NKG2D表达的阳性率分别为16.16%和78.45%,乏氧条件下二者表达的阳性率分别为15.16%和71.08%;rhIL-2上调NKG2A和NKG2D的表达,乏氧不影响 rhIL-2对NKG2D、 NKG2A的上调作用;rhIL-2显著上调NK细胞CD44的表达,乏氧抑制CD44的表达（P<0.05）。结论: 乏氧下调外周血NK细胞表面受体NKG2D及CD44的表达,但对NKG2A的表达无显著影响。由此提示,NKG2D及CD44分子可能在乏氧引起的NK细胞杀伤活性抑制中具有重要作用。