特发性血小板减少性紫癜与细胞免疫失调

特发性血小板减少性紫癜 (ITP)是一种常见自身免疫性出血性疾病 ,以自身抗体介导的破坏性血小板减少为特征 ,其具体发病机制十分复杂。近年来发现细胞免疫功能紊乱与ITP发病密切相关。本文就参与细胞免疫的 T淋巴细胞亚群及与细胞免疫有关的多种细胞因子在 ITP中的改变及可能机制作一综述。1　 T细胞亚群在 ITP中改变近年来实验证明 ,T淋巴细胞是参与细胞免疫的主要成分 ,而辅助 T细胞与抑制 T细胞亚群间的平衡是维持免疫内环境稳定的中心环节。宋强〔1〕等检测 42例 ITP患者 T细胞亚群的变化。研究结果显示 ,ITP患者外周血平均 C…     

特发性血小板减少性紫癜中T细胞和细胞因子异常的研究进展

特发性血小板减少性紫癜是一种慢性获得性器官特异的自身免疫性疾病，其病因尚未明确，目前公认与免疫因素有关。CD4^ T细胞是机体的重要调节细胞，CD4^ T细胞激活后增殖分化为Th1、Th2效应细胞，通过表达不同的细胞因子介导各自的免疫功能。Th细胞及其细胞因子与特发性血小板减少性紫癜的关系引起许多学者的兴趣，本文试就近年来这方面的研究进展作一综述。     

特发性血小板减少性紫癜中T细胞和细胞因子异常的研究进展

特发性血小板减少性紫癜是一种慢性获得性器官特异的自身免疫性疾病,其病因尚未明确,目前公认与免疫因素有关。CD4+T细胞是机体的重要调节细胞,CD4+T细胞激活后增殖分化为Th1T、h2效应细胞,通过表达不同的细胞因子介导各自的免疫功能。Th细胞及其细胞因子与特发性血小板减少性紫癜的关系引起许多学者的兴趣,本文试就近年来这方面的研究进展作一综述。     

激素对慢性特发性血小板减少性紫癜的疗效观察

目的 观察糖皮质激素对不同病程慢性特发性血小板减少性紫癜的疗效.方法 将我科收治的90例慢性特发性血小板减少性紫癜患者按照从发病到就诊时间随机分为三组:1月组、半年组、1年组.三组字接受治疗,除采用支持治疗外,均用泼尼松1mg/(kg·d)分2次口服,连用6个月.结果 半年组疗效优于1月组(P<0.05),1年组疗效优于半年组(P<0.05).结论 泼尼松对慢性特发性血小板减少性紫癜的疗效与病程相关,早期即时接受激素治疗患者的疗效好.     

丙种球蛋白治疗小儿急性特发性血小板减少性紫癜临床观察

目的 观察静脉注射大剂量丙种球蛋白(IVIg)治疗小儿急性特发性血小板减少性紫癜(ITP)疗效.方法 对我院2005年1月～2010年1月收治的小儿急性特发性血小板减少性紫癜54例患者随机分为两组,静脉注射大剂量丙种球蛋白组28例,予丙种球蛋白静脉注射0.4g/(kg.d),连用5天,之后每月静脉注射一天,连用4月;糖皮质激素治疗组26例,予静脉注射地塞米松0.5mg/(kg·d),连用5天,之后改为泼尼松每日1mg/kg口服,并逐渐减量至口服4～6周后停药.观察两组治疗效果.结果 大剂量丙种球蛋白静脉注射治疗组血小板开始上升时间为2.25±1.23天,上升至正常时间为4.75±1.35天,出血控制时间为2.75±1.25天,激素治疗组分别为8.75±3.25天、13.25±5.52天、10.4±4.25天,两组有显著差异(P<0.01).大剂量丙种球蛋白静脉注射治疗组总有效率为96.5%,激素组为80.7%,两组有明显差异(P<0.05).结论 大剂量丙种球蛋白静脉注射治疗小儿急性ITP时间短、起效快,有效率高,可降低ITP急性期大出血的危险性.     

EB病毒感染与儿童特发性血小板减少性紫癜的关系

为探讨EB病毒（EBV）与儿童ITP之间的关系，应用免疫酶染色法对ITP患儿血清进行了EBVVCA—lgM检测，结果报道如下。     

难治性特发性血小板减少性紫癜治疗的进展

特发性血小板减少性紫癜 (ITP)是以血小板显著减少为特征 ,好发于儿童和成人的常见疾病。传统口服激素和切脾仅能使部分患者达到完全缓解。对于传统治疗效果不佳的病例属难治性 ITP。目前对这部分病例开展了许多试验性治疗探索 ,现介绍如下 :1　大剂量甲基强的松龙冲击治疗难治性 ITP对口服激素无效的病例采用大剂量甲基强的松龙冲剂治疗 (1 5 m g.kg- 1 .d- 1 )约 5 0 %的患者有效 ,对急性、有严重出血者尤为适用。没有严重的副作用。研究认为大剂量甲基强的松龙可作为对常规治疗无效的 ITP患者紧急情况下和术前治疗的较好方法〔1〕。…     

丙种球蛋白和地塞米松对儿童急性特发性血小板减少性紫癜的疗效观察

目的 评价用静脉丙种球蛋白(IVIG)、地塞米松(DEX)和IVIG加DEX 3种方法对小儿急性特发性血小板减少紫癜(AITP)的治疗效果的近期观察。方法 30名AITP患儿随机分为IVIG、DEX和IVIG加DEX3组,观察治疗后血小板变化及出血症状控制时间。结果 静脉滴注IVIG 1d,IVIG 1d加DEX 7d和DEX 3组治疗后血小板(Tc)≤50×10~9/L的人数所占比例使用IVIG组明显减少,而Tc≥50×10~9/L与Tc≥100×10~9/L开始的时间和出血症状控制时间,2组IVIG与DEX组相比有显著性差异(P<0.005)。结论 对AITP患儿应首先IVIG或IVIG加地塞米松治疗。     

特发性血小板减少性紫癜患儿外周血T细胞PKC活性变化的研究

为了探讨ITP患儿外周血T细胞蛋白激酶C(PKC)的活性变化及其与T细胞活化和血小板减少程度之间的关系,无菌采集35例ITP患儿及30例正常儿童外周血,采用T细胞分离富集柱法分离纯化T细胞,分别用非同位素标记法检测T细胞PKC的活性变化,用流式细胞仪检测T细胞活化标志FasL蛋白的表达,血细胞计数仪计数血小板的减少程度。结果ITP患儿T细胞PKC的总活性与正常儿童相比明显增强[(0.97±0.21)nmol/ml·min和(0.55±0.13)nmol/ml·min,x±s,P<0.05],T细胞活化标志FasL蛋白表达与正常儿童比较显著升高(CD4+TFasL:32.7%±3.4%和14.7%±4.2%;CD8+TFasL:17.3%±9.7%和11.6%±8.5%,x±s,P<0.05),并且T细胞PKC的活性变化与CD4+TFasL、CD8+TFasL的表达均为显著正相关(r1=0.68,r2=0.53,P<0.05),与血小板计数成显著负相关(r=-0.75,P<0.05)。上述研究结果表明ITP患儿PKC活性增强可能引起T细胞的活化,活性T细胞增多可导致患儿血小板大量损伤,提示PKC信号转导在ITP的免疫病理机制中发挥重要作用。     

Prognostic factors of response to laparoscopic splenectomy in patients with idiopathic thrombocytopenic purpura

Laparoscopic splenectomy (LS) has become the treatment of choice for patients with idiopathic thrombocytopenic purpura (ITP) who do not respond to medical treatment. The aim of this study was to identify factors predictive of outcome after LS for ITP. From May 1997 to December 2002, we performed 30 LS on patients with ITP. A positive response was defined as a postoperative platelet count greater than 50,000/micro L and no requirement for maintenance therapy. Chi-square testing was performed to determine the predictive effects of the following variables: age, sex, preoperative response to steroids or immunoglobulin, duration of disease, antiplatelet antibody, platelet associated antibody, and antinuclear antibody. LS was successfully performed in all patients. For a mean follow-up interval of 24.3 months, response to LS was 73.3%. Splenectomy for steroid nonresponders resulted in an inferior complete response rate (10 of 18, 55.6%) as compared with those that experienced relapse after steroid treatment (11 of 12, 91.7%) (p=0.042). The other significant predictor of outcome by univariate analysis was the time between diagnosis and surgery (p=0.049). The other variables showed no significant correlation with successful splenectomy. We conclude that LS can be performed safely with a satisfactory remission rate in patients with ITP who do not respond to medical treatment, and that the factors most frequently associated with surgical success are a response to steroid and disease duration.     

Primary percutaneous coronary intervention for acute myocardial infarction with idiopathic thrombocytopenic purpura: a case report

Acute myocardial infarction (AMI) is rare in patients with idiopathic thrombocytopenic purpura (ITP). We describe a case of an AMI during thrombocytopenia in a patient with chronic ITP. A 47-yr-old woman presented with anterior chest pain and a low platelet count (21,000/microliter) at admission. Urgent coronary angiography revealed total occlusion of proximal right coronary artery and primary percutaneous coronary intervention (PCI) was performed successfully. This case suggests that primary PCI may be a therapeutic option for an AMI in patients with ITP, even though the patient had severe thrombocytopenia.     

Outcome of immunosuppressive therapy with Helicobacter pylori eradication therapy in patients with chronic idiopathic thrombocytopenic purpura

We initiated this study to investigate whether combining Helicobacter pylori eradication with immunosuppressive therapy provides an additional benefit to patients with idiopathic thrombocytopenic purpura (ITP) that has relapsed or has not responded to steroid and/or danazol therapy in patients who have H. pylori infection. Thirty- four patients with chronic ITP that had relapsed or failed to steroid and/or danazol therapy were assessed for H. pylori infection. Of the 21 confirmed cases, 12 patients were given H. pylori eradication therapy alone (EA), while 9 patients received eradication therapy combined with immunosuppressive therapy (EI). The response rate was not significantly different between patients in the EA and those in the EI group (41.7% in the EA group vs. 66.7% in the EI group, p=0.345). The median platelet count at 6 months after therapy was higher in the EI group patients (75 x 10(9)/L in the EI group patients vs. 18 x 10(9)/L in the EA group patients, p=0.028). The median response duration was also longer in the EI group patients (9 months in the EI group patients vs. 3 months in the EA group patients, p=0.049). These results show that a significant benefit is gained by the use of H. pylori eradication combined with immunosuppressive therapy over the use of eradication therapy alone for patients with chronic ITP.     

Long-term follow-up of laparoscopic splenectomy in patients with immune thrombocytopenic purpura

Laparoscopic splenectomy (LS) has been reserved for intractable and relapsing immune thrombocytopenic purpura (ITP) despite medical treatment. With further experiences of LS in ITP, we investigated long term outcomes of LS, especially newly developed morbidities, and tried to find predictive factors for favorable outcomes. From August 1994 to December 2004, fifty-nine patients whose follow-up period was more than 12 months after LS were investigated. After a long-term follow-up (median 54 months, range 12.5-129 months), a complete response (CR) was found in 28 patients (47.5%), partial response in 24 (40.7%), and no response in 7 (11.9%). The relapse rate during follow-up periods was 15.2%. The rapid response group (p=0.017), in which the platelet count increased more than twice of the preoperative platelet count within 7 days after LS, relapsing after medical treatment (p=0.02), and the satisfactory group as the initial result of LS (p=0.001) were significant for predicting CR in univariate analysis, but only the initial satisfactory group was an independent predictive factor for CR in multivariate analysis (p=0.036, relative risk=6419; 95% CI, 1.171-35.190). Infections were the most frequent morbidities during the follow-up period, which were treated well without mortality. LS is a safe and effective treatment modality for ITP. Active referral to surgery might be required, considering complications and treatment results related to long-term use of steroid-based medications.     

Effect of protein kinase C on proliferation and apoptosis of T lymphocytes in idiopathic thrombocytopenic purpura children

It is well-documented that T lymphocyte proliferation and apoptosis are abnormal in idiopathic thrombocytopenic purpura （ITP） children. However, the underlying regulation mechanisms especially in terms of signal transduction remain unknown. In this paper, we reported the changes of protein kinase C （PKC） activity in peripheral blood T lymphocytes and the effect of PKC on T lymphocyte proliferation and apoptosis. We demonstrated that in ITP children, the activator （PMA） and inhibitor （H-7） of PKC affected on T lymphocyte proliferation and apoptosis dramatically, but they altered little in healthy children. PKC activity was significantly enhanced in ITP children together with an increased expression of FasL on CD3^＋ T, CD4^＋T and CD8^＋T cells, resulting in a positive correlation between PKC activity and the expression of FasL on T cells. While the PKC activity and the platelet count were negatively correlated. Taken together, our findings suggest that the PKC activation may enhance T lymphocytes activity, suppress T cell apoptosis and be involve in thrombocytes damage as a mechanism related to immune pathogenesis of ITP. Cellular ＆ Molecular Immunology. 2005; 2（3）： 197-203.     

血小板相关抗体与原发性血小板减少性紫癜关系的研究进展

原发性血小板减少性紫癜 (idiopathicthrombocy topenicpurpura ,ITP)是一种自身免疫性血小板减少症 ,血小板减少的机制是由于自身免疫功能异常导致血液中产生血小板相关抗体 ,使循环中血小板破坏增加。ITP是由血小板自身抗体所引起的综合征 ,为临床常见的出血性疾病 ,其主要病理是血小板抗体的产生并吸附于血小板表面后加速血小板从循环中的清除 ,这些抗体作用的血小板膜靶抗原可多种多样 ,其中血小板膜上糖蛋白 (glycoprotein ,GP)Ⅱb/Ⅲa是一重要靶抗原 ,少数针对GPⅠb/ⅠX复合物。由于抗体直接作用于GPⅡb/Ⅲa、GPⅠb/ⅠX等 ,使…     

原发性血小板减少性紫癜患者T细胞受体Vβ亚家族基因的表达特点

目的：了解原发性血小板减少性紫癜（ITP）患者T细胞受体 Vβ亚家族基因表达特点。 方法： 采用反转录酶－多聚酶链反应（RT-PCR）方法检测5例ITP患者外周血T细胞TCR Vβ 24个亚家族基因表达情况，10例正常人作为对照。 结果： 正常人外周血T细胞表达全部24个TCR Vβ亚家族，而5例ITP患者外周血T细胞仅表达4-11个Vβ亚家族，主要为Vβ2（100％）和Vβ3（100％），其次为Vβ19（80％）和Vβ21（80％）部分。全部样本未检测出Vβ4、Vβ6、Vβ17、Vβ20、Vβ24亚家族表达。 结论： ITP患者外周血T细胞TCR Vβ基因谱系呈限制性表达，与其存在细胞免疫功能异常有关。     

Transient disappearance of immunologic disorders and remission after intercurrent measles infections in children with chronic idiopathic thrombocytopenic purpura

In two children with chronic idiopathic thrombocytopenic purpura (ITP) a transient remission of thrombocytopenia was observed after intercurrent measles infection. Both cases were girls who had a long history of thrombocytopenia. During acute measles infection, the delayed hypersensitivity response was suppressed. Total T lymphocytes, T-cell subsets, especially OKT4 cells, the lymphoproliferative response, and interleukin-2 (IL-2) and -interferon production were decreased accompanying normalization of the OKT4/OKT8 ratio. However, OKT4 cells remained at a reasonably low level and the lymphoproliferative response stimulated with pokeweed mitogen was still in the lower normal range. Direct immunofluorescent study demonstrated that the measles antigen was present in the mononuclear cells, especially OKT4 cells. The levels of platelet-associated IgG antibody (PAIgG) and IgG circulating immune complex (CIC) were undetectable. One month later, the OKT4/OKT8 ratio lymphoproliferative response significantly increased, IL-2 and -interferon production increased, and PAIgG and IgG CIC reappeared with the relapse of thrombocytopenia. There was also a significant increase inin vitro IgG production due to the presence of patient OKT8 cells and/or OKT4 cells. However, there was no enhancement in the presence of patient B cells. This suggests that the presence of specific OKT4 helper T cells and a defect in the suppressor function of suppressor OKT8 cells contribute to an overproduction of IgG and the appearance of PAIgG accompanied by thrombocytopenia. The transient remission associated with measles infection is probably related to the effect of the virus on the helper T cells, resulting in a decrease in specific OKT4 helper T cells and normalization of the OKT4/OKT8 ratio, suppression of IL-2 and -interferon production, and platelet-associated IgG production.     

Perisinusoidal fibrosis of the liver in patients with thrombocytopenic purpura

Summary 10 patients with thrombocytopenic purpura (TP) underwent splenectomy. Eight of these patients had idiopathic TP (certain or probable). All had normal liver function tests. Liver histology of the surgical biopsy was normal with the exception of a non specific mild portal infiltration in 6 cases. On Sirius red staining the perisinusoidal network was normal in 3 cases, mildly or moderately increased in 5 cases and often associated with perivenular fibrosis. Collagen types I, III, IV, laminin and fibronectin were increased in the 8 biopsies tested. On semi-thin sections, numerous Kupffer cells were observed. Under the electron microscope, sinusoidal abnormalities were very similar in all 7 patients studied: numerous Kupffer cells containing abundant lysosomes, numerous collagen bundles in the Disse space, active endothelial cells, transformation of some perisinusoidal cells into cells with some of the characteristics of fibroblasts (increased RER) and myofibroblasts (peripheral condensations of the filamentous network), increased fragments of basement membrane-like material. In two cases there was an increase in the number of perisinusoidal cells loaded with lipids. The similarity of the lesions and the absence of other fibrogenic causes (except in 2 cases) suggest that TP may represent another group of diseases with perisinusoidal fibrosis. The aetiology of fibrosis remains unknown but platelet derived growth factor and activated macrophages may play a major role.