Increased apoptosis of immunoreactive host cells and augmented donor leukocyte chimerism, not sustained inhibition of B7 molecule expression are associated with prolonged cardiac allograft survival in mice preconditioned with immature donor dendritic cells plus anti-CD40L mAb.

BACKGROUND: We previously reported the association among donor leukocyte chimerism, apoptosis of presumedly IL-2-deficient graft-infiltrating host cells, and the spontaneous donor-specific tolerance induced by liver but not heart allografts in mice. Survival of the rejection-prone heart allografts in the same strain combination is modestly prolonged by the pretransplant infusion of immature, costimulatory molecule-(CM) deficient donor dendritic cells (DC), an effect that is markedly potentiated by concomitant CM blockade with anti-CD40L (CD154) monoclonal antibody (mAb). We investigated whether the long survival of the heart allografts in the pretreated mice was associated with donor leukocyte chimerism and apoptosis of graft-infiltrating cells, if these end points were similar to those in the spontaneously tolerant liver transplant model, and whether the pretreatment effect was dependent on sustained inhibition of CM expression of the infused immature donor DC. In addition, apoptosis was assessed in the host spleen and lymph nodes, a critical determination not reported in previous studies of either spontaneous or "treatment-aided" organ tolerance models. METHODS: Seven days before transplantation of hearts from B10 (H-2b) donors, 2x10(6) donor-derived immature DC were infused i.v. into C3H (H-2k) recipient mice with or without a concomitant i.p. injection of anti-CD40L mAb. Donor cells were detected posttransplantation by immunohistochemical staining for major histocompatibility complex class II (I-Ab) in the cells of recipient lymphoid tissue. CM expression was determined by two-color labeling. Host responses to donor alloantigen were quantified by mixed leukocyte reaction, and cytotoxic T lymphocyte (CTL) assays. Apoptotic death in graft-infiltrating cells and in areas of T-dependent lymphoid tissue was visualized by terminal deoxynucleotidyltransferase-catalyzed dUTP-digoxigenin nick-end labeling and quantitative spectrofluorometry. Interleukin-2 production and localization were estimated by immunohistochemistry. RESULTS: Compared with control heart transplantation or heart transplantation after only DC administration, concomitant pretreatment with immature donor DC and anti-CD40L mAb caused sustained elevation of donor (I-Ab+) cells (microchimerism) in the spleen including T cell areas. More than 80% of the I-Ab+ cells in combined treatment animals also were CD86+, reflecting failure of the mAb to inhibit CD40/ CD80/CD86 up-regulation on immature DC in vitro after their interaction with host T cells. Donor-specific CTL activity in graft-infiltrating cells and spleen cell populations of these animals was present on day 8, but decreased strikingly to normal control levels by day 14. The decrease was associated with enhanced apoptosis of graft-infiltrating cells and of cells in the spleen where interleukin-2 production was inhibited. The highest levels of splenic microchimerism were found in mice with long surviving grafts (>100 days). In contrast, CTL activity was persistently elevated in control heart graft recipients with comparatively low levels of apoptotic activity and high levels of interleukin-2. CONCLUSION: The donor-specific acceptance of rejection-prone heart allografts by recipients pretreated with immature donor DC and anti-CD40L mAb is not dependent on sustained inhibition of donor DC CM (CD86) expression. Instead, the pretreatment facilitates a tolerogenic cascade similar to that in spontaneously tolerant liver recipients that involves: (1) chimerism-driven immune activation, succeeded by deletion of host immune responder cells by apoptosis in the spleen and allograft that is linked to interleukin-2 deficiency in both locations and (2) persistence of comparatively large numbers of donor-derived leukocytes. These tolerogenic mechanisms are thought to be generic, explaining the tolerance induced by allografts spontaneously, or with the aid of various kinds of immunosuppression.     

白细胞介素12对肝癌基因治疗的实验研究

目的 研究携带白细胞介素１２（ＩＬ－１２）基因逆转录病毒载体对体内肝癌生长抑制作用,探索基因治疗肝癌新途径。方法 构建携带ＩＬ－１２的逆转录病毒载体,转染逆转录病毒包装细胞系ＰＡ３１７,应用该包装细胞对实验性肝癌大鼠进行治疗,观察抗肿瘤作用,免疫功能变化。     

急性非淋巴细胞白血病中MGMT与p53基因突变的研究

目的 探讨肿瘤抑制基因ｐ５３、ＭＧＭＴ在急性非淋巴细胞白血病（ＡＮＬＬ）中的改变。方法 用聚合酶链反应－单链构象多态性（ＰＣＲ－ＳＳＣＰ）技术对３１例ＡＮＬＬ患者、２２例正常人ｐ５３基因第５、６、７、８外显子和ＭＧＭＴ基因第１、４外显子进行突变分析。结果 ３１例ＡＮＬＬ中５例存在ｐ５３基因突变、４例存在ＭＧＭＴ基因突变,其中２例ｐ５３与ＭＧＭＴ同时发生突变。结论 ｐ５３基因突变在白血病发生中起一定     

铝-铬天青-溴化十六烷基啶胶束增溶分光光度法测定血清铝的方法研究

在溶液p H6-5 ～5-5 范围内,铝铬天青S(CAS)溴化十六烷基吡啶(CPB) 生成兰色三元胶束配合物,它的最大吸收在618n m 波长,摩尔吸光系数ε为9-642 ×104L.m ol-1 .c m -1 。在铝含量0 ～6-0 ×10 -6m ol.L- 1,遵循比耳定律,AlCASCPB三元配合物的组成摩尔比是1∶2∶3 。一定量的抗坏血酸和盐酸羟胺可以消除血清中与铝共存的其它阳离子Fe3 ,Cu2 等的干扰。该方法的检出限为6-60 ×10 - 7mol .L-1 ,平均回收率(96-11 ±2-87) % ,相对标准差小于3 % 。方法简便易行,有较高的准确度和灵敏度,用于血清铝的测定可获得满意结果     

中俄,中哈边境地区莱姆病自然疫源地调查研究

目的：调查边境地区莱杂姆病和自然疫源地的状况。方法;对血清学、病原学、宿主、媒介,病例和地理景观方面进行调查。结果：用ＩＦＡ和ＥＬＩＳＡ法共检测人畜血清１５０１份,从１９９份人血清中检出抗体阳性１８份,阳性率为９．０５％,并发现莱姆病典型患者１５例;检查马血清２０份,阳性５份,阳性率为２５．００％;检查牛血清３９９份,阳性６９份,阳性率１７．２９％;检查羊血清８８３份,阳性１９９份,阳性率２２．５     

健康教育行为干预对降低小学生肠道寄生虫感染率的研究

为研究健康教育行为干预对降低小学生肠道寄生虫感染率的效果,探讨小学生肠道寄生虫病的防治方法,在苍山县随机选取860名小学生进行为期2年的研究.单纯健康教育行为干预组、行为干预加驱虫组、单纯驱虫组及对照组,肠道寄生虫感染率实验前分别为64.13%、61.23%、63.12%和60.70%,实验后分别为41.67%、26.52%、53.57%和60.61%.结果表明:健康教育行为干预对降低小学生肠道寄生虫感染率具有重要作用;健康教育行为干预加针对性驱虫是控制小学生肠道寄生虫感染的最佳模式.     

准分子激光原位角膜磨镶术后屈光回退与术中角膜床厚度的关系

目的　探讨准分子激光原位角膜磨镶术（ｅｘｃｉｍｅｒ ｌａｓｅｒ ｉｎｓｉｔｕ ｋｅｒａｔｏｍｉｌｅｕｓｉｓ ＬＡＳＩＫ） 矫治高度近视后屈光回退与术中角膜床厚度的关系。方法　对４７６ 例９３８ 只眼在我院接受Ｌａｓｉｋ 治疗的患者中,发生屈光回退的病例９６ 例,１８９ 只眼与未发生屈光回退的病例３８０ 例７４９ 只眼术中角膜床厚度及术前、术后１ ｗ ｋ 、１ 、３ 、６ ｍ ｏ 屈光状态的资料进行对比分析。结果　有屈光回退眼组比无屈光回退眼组平均角膜床厚度小;屈光回退眼组屈光回退程度（ 术后６ ｍｏ 时） 与角膜床厚度呈负相关系,上述结果经统计学检验均有显著性差异（ Ｐ ＜ ００１） ;有屈光回退眼组术后早期（１ ｗｋ） 屈光状态略成过矫,但其后屈光回退程度在０ ．５ａ 内呈加重趋势。结论　高度近视准分子激光原位角膜磨镶术中的角膜床厚度是影响术后屈光稳定性的重要因素     

复发性单纯疱疹性角膜炎患者血清IL-2及SIL-2R水平的研究

目的研究复发性单纯疱疹性角膜炎患者血清白细胞介素-2（IL－2）及其可溶性白细胞介素-2受体（SIL－2R）水平。方法本文测定了30例复发性单纯疱疹性角膜炎患者（实验组）和25例健康人（对照组）血清白细胞介素－2（IL－2）及其可溶性白细胞介素－2受体（SIL－2R）的水平。结果对照组IL－2的水平为5．41±1．45mg·L－1,实验组IL－2R水平为2．80±1.47mg·L-1,2组比较t＝2．90,P＜0．01,说明复发性单纯疱疹性角膜炎患者血清IL－2水平较对照组明显降低。对照组SIL－2R水平为90．86±17．90mg·L－1,实验组SIL－2R水平为171·46±19.30mg·L－1,2组比较t＝5．17,P＜0．01。复发性单纯疱疹性角膜炎患者血清SlL－2R水平较对照组显著升高。结论复发性单纯疱疹性角膜炎患者体内免疫功能紊乱,血清IL－2活性降低、SlL－2R水平升高可能是其原因之一,这也为免疫治疗提供了一定依据。     

Prevention of experimental autoimmune anterior uveitis by anterior chamber-associated immune deviation

目的实验性自身免疫性前葡萄膜炎（ＥＡＡＵ）是研究人前葡萄膜炎的有用模型。本研究旨在观察前房相关免疫偏离（ＡＣＡＩＤ）能否阻止ＥＡＡＵ发生。方法将溶于磷酸盐缓冲液（ＰＢＳ）的牛黑色素蛋白（ＢＭＰ）注射于大鼠右眼前房;对照组动物仅注射ＰＢＳ。７ｄ后,使用添加完全福氏佐剂（ＣＦＡ）的ＢＭＰ和百日咳毒素免疫所有动物。通过临床观察和组织病理学检测葡萄膜炎的严重程度和发病率。通过由注射ＢＭＰ刺激的足垫水肿反应评估迟发型超敏反应（ＤＴＨ）。结果与对照组相比,预先眼内注射ＢＭＰ的大鼠,其ＥＡＡＵ的严重程度和发病率减低,且ＤＴＨ反应受到显著抑制。结论这些资料提示ＡＣＡＩＤ可以用来阻止ＥＡＡＵ的发生。