血小板特异性抗体的测定与特发性血小板减少性紫癜的关系

特发性血小板减少性紫癜 (ＩＴＰ)发生的主要原因是抗血小板自身抗体引起的血小板破坏 ,因而血小板自身抗体的检测对ＩＴＰ的诊断及发病机理的研究有重要价值。本研究用改良的血小板抗原单抗特异性固相化法 (ｍｏｎｏｃｌｏｎａｌａｎｔｉｂｏｄｙｓｐｅｃｉｆｉｃｉｍｍｏｂｏｌｉｚａｔｉｏｎｏｆｐｌａｔｅｌｅｔａｎｔｉｇｅｎｓ ,ＭＡＩＰＡ)测定了ＩＴＰ患儿和非免疫性血小板减少症患儿血清中的抗ＧＰＩＩｂ/ＩＩＩａ和抗ＧＰＩｂ/Ｉｘ自身抗体 ,并同时测定这些患儿的血小板表面相关抗体 (ＰＡＩｇＧ) ,将二者作比较 ,试图评价血小板…     

MDM2mRNA过度表达与儿童急性淋巴细胞白血病免疫分型、FAB分型及高白细胞

为了研究癌基因ＭＤＭ２ｍＲＮＡ过度表达与儿童急性淋巴细胞白血病（ＡＬＬ）的免疫分型、ＦＡＢ分型及临床高白细胞性的关系,用ＲＴ－ＰＣＲ法检测了３２例急性洒在病患儿外周血单个核细胞内ＭＤＭ２ｍＲＮＡ过度表达与不同型别的关系。高白细胞性白血病（ＨＡＬ）ＭＤＭ２表达明显高于非高白细胞性白血病（ＮＨＡＬ）组（Ｐ＝０．００９９）;Ｔ淋巴细胞白血病（Ｔ－ＡＬＬ）与非Ｔ淋巴细胞白血病（Ｎｏｎ－Ｔ－ＡＬＬ）间（Ｐ＝０．７３４５）,Ｌ１型急性淋巴细胞白血病与Ｌ２型间（Ｐ＝０．８９２３）的ＭＤＭ２ｍＲＮＡ表达水平无差异。提示ＭＤＭ２ｍＲＮＡ过度表达与儿童急性淋巴细胞白血病的高白细胞性相关。     

70例原发性血小板减少性紫癜PLT与MPV,PDW和MK的关系

为了探讨原发性血小板减少性紫癜、患儿血小板计数与血小板平均体积、血小板分布宽度（ＰＤＷ）和骨髓巨核细胞数（ＭＫ）的关系,应用意大利产ＳＥＡＣ－Ｈ１２血球计数仪,对７０例ＩＴＰ患儿采毛细血管血做了２６４人次ＰＬＴ、ＭＰＶ和ＰＤＷ检测,其中５９例患儿在上述检查当日做骨髓穿刺涂片检测巨核细胞。结果：（１）ＰＬＴ≤９０＊１０＾９／Ｌ时,ＰＬＴ与ＭＰＶ呈高度正相关,ＰＬＴ〉９０＊１０＾９／Ｌ时,ＰＬＴ和ＭＰ     

特发性血小板减少性紫癜与人细小病毒B19感染的关系

目的 研究人细小病毒Ｂ１９（ＨＰＶ Ｂ１９）感染与特发性血小板减少性紫癜（ＩＴＰ）的关系。方法 应用巢式聚合酶链反应技术检测８４例ＩＴＰ患儿存档骨髓涂片标本中ＨＰＶ Ｂ１９－ＤＮＡ,并以２４例巨幼细胞性贫血（ＭＡ）患儿为对照。结果 ８４例ＩＴＰ骨髓中ＨＰＶ Ｂ１９－ＤＮＡ阳性３６例,阳性率为４３％,２４例ＭＡ患儿骨髓中ＨＰＶ Ｂ１９－ＤＮＡ阳性３例,阳性率为１２％,（χ＾２＝６．１９９,Ｐ〈０．０     

70例原发性血小板减少性紫癜PLT与MPV、PDW和MK的关系

为了探讨原发性血小板减少性紫癜（ＩＴＰ）、患儿血小板计数（ＰＬＴ）与血小板平均体积（ＭＰＶ）、血小板分布宽度（ＰＤＷ）和骨髓巨核细胞数（ＭＫ）的关系,应用意大利产ＳＥＡＣ－Ｈ１２血球计数仪,对７０例ＩＴＰ患儿采毛细血管血做了２６４人次ＰＬＴ、ＭＰＶ和ＰＤＷ检测,其中５９例患儿在上述检查当日做骨髓穿刺涂片检测巨核细胞数。结果：（１）ＰＬＴ≤９０×１０９／Ｌ时,ＰＬＴ与ＭＰＶ呈高度正相关,ＰＬＴ＞９０×１０９／Ｌ时,ＰＬＴ与ＭＰＶ无正相关;（２）ＰＬＴ≤９０×１０９／Ｌ时,ＰＬＴ与ＰＤＷ是高度正相关,ＰＬＴ＞９０×１０９／Ｌ时,ＰＬＴ与ＰＤＷ无正相关;（３）ＰＬＴ≤９０×１０９／Ｌ时,ＰＬＴ与ＭＫ是高度正相关,ＰＬＴ＞９０×１０９／Ｌ时,ＰＬＴ与ＭＫ无正相关。     

特发性血小板减少性紫癜患儿T细胞免疫功能的变化

目的 探讨Ｔ淋巴细胞亚群、白细胞介素１０（ＩＬ－１０）、γ－干扰素（ＩＦＮ－γ）在特发性血小板减少性紫癜（ＩＴＰ）中的变化及其用地塞米松（ＤＥＸ）治疗的影响。方法 采用ＤＥＸ治疗ＩＴＰ患儿,分别于治疗前后采取静脉血标本,应用改良碱性磷酸酶－抗碱性磷酸酶（ＡＰＡＡＰ）法及酶标记免疫吸附测定（ＥＬＩＳＡ）法分别检测Ｔ细胞亚群及血清ＩＬ－１０、ＩＦＮ－γ的含量。结果 ＩＴＰ患儿ＤＥＸ治疗前外周血ＣＤ４＾     

肾病综合征患儿血浆血小板活化因子尿溶血小板活化因子的变化

用血小板自动平衡聚集仪建立血小板活化因子的生物活性检测法。测定２２例单纯性肾病（ＳＮ）和１６例肾炎性肾病（ＮＮ）患儿血浆血小板活化因子（ＰＡＦ）和尿溶血小板活化因子（ｌｙｓｏ－ＰＡＦ）的水平。结果表明，ＳＮ及ＮＮ患儿肾病期血、尿ＰＡＦ均明显高于对照组；缓解期ＳＮ患儿血、尿ＰＡＦ恢复正常，但ＮＮ患儿仍高于对照组；尿ｌｙｓｏ－ＰＡＦ的水平和尿蛋白的排泄呈正相关。提示ＰＡＦ可能参与了肾病综合征的发病，ＰＡＦ是诱导肾小球基底膜对蛋白通透性增加的一个重要介质。     

正常肌肉和Duchenne肌营养不良肌肉中脑型一氧化氮合酶mRNA及 …

目的 检测正常人与Ｄｕｃｈｅｒｎｎｅ肌营养不良症（ＤＭＤ）患儿肌肉中脑型一氧人 酶（ｎＮＯＳ）ｍＲＮＡ及其蛋白的表达水平。方法 建立高敏感性的ＲＮＡ酶保护实验,并通过Ｗｅｓｔｅｒｎｂｌｏｔ分析的方法,对１０例ＤＭＤ肌肉标本和５例正常儿童肌肉标本中ｎＮＯＲｍＲＮＡ及其蛋白表达情况进行检测。结果 ＤＭＤ患儿肌肉中ｎＮＯＳｍＲＮＡ的表达量只有正常肌肉的１０％、ｎＮＯＳ蛋白亦有相同的表达规律。结论ｎＮＯＲ     

血小板生成素在新生儿血小板减少症中的应用

37年前Ｋｅｌｅｍｅｎ首先发现动物血液中存在着调节血小板生成的体液因子 ,命名为血小板生成素 (ＴＰＯ)。但在随后的几十年中 ,由于检测手段的限制 ,使这种调节血小板生成的激素 ,先后改名为血小板生成刺激因子和巨核细胞刺激因子 ,直到 1994年成功地克隆出人类ＴＰＯ补偿脱氧核糖核酸(ｃＤＮＡ)和基因后 ,ＴＰＯ这一概念才被人们开始接受。随着分子生物学的进展和分子生物学技术的应用 ,已成功地应用重组ＤＮＡ技术 ,产生重组人类ＴＰＯ(ｒｈＴＰＯ) ,并在试管内、动物体内和人体内作了大量实验。本文将对ＴＰＯ的生物学特性以及在血小板…     

休克患儿磷脂酶A_2及细胞因子作用研究

目的探讨血清磷脂酶Ａ２（ＰＬＡ２）及细胞因子在休克发生发展中的作用及意义。方法采用ＥＬＩＳＡ法检测１６例休克患儿及２０例健康儿童血清ＰＬＡ２、肿瘤坏死因子（ＴＮＦ－ａ）及白细胞介素（ＩＬ～６）含量,并作临床脏器功能监测、血乳酸、血糖、动脉血气分析及血小板计数。结果休克患儿血清ＰＬＡ２（０．８９±０．６３ｍｐ／Ｌ）、ＴＮＦ－ａ（０、６３±０．２５ｍｇ／Ｌ）及ＩＬ－６（６．８４±１９７ｍｇ／Ｌ）浓度均较正常对照组（０．１７±０．０２ｍｇ／Ｌ、０．０８±０．０１ｍｇ／Ｌ、２．３２±０．６２ｍｇ／Ｌ）明显升高（Ｐ＜０．００１）;多器官功能衰竭组（ＭＳＯＦ）上述３项指标（ＰＬＡ２１．１７±０．７０ｍｇ／Ｌ、ＴＮＦ－ａ０．９１±０．２７ｍｐ／Ｌ、ＩＬ－６７．７０±１．４０ｍｇ／Ｌ）均显著高于单器官功能衰竭组（ＳＯＦ）（ＰＬＡ２０．４８±０．０７ｍｇ／Ｌ、ＴＮＦ－ａ０．４７±０．０５ｍｇ／Ｌ、ＩＬ－６５．５５±０．７０ｍｇ／Ｌ）,死亡组明显高于治愈组。结论ＰＬＡ２水平与病情轻重有关,可作为早期预测ＭＳＯＦ发生的参数、评估治疗效果及预后。选择性投用ＰＬＡ２抑制剂可能成为治疗休克的有效方法。     

Thrombopoietin in preterm infants: gestational age-dependent response

PURPOSE: To investigate the factors affecting thrombopoietin (TPO) levels in preterm infants and to determine if TPO levels differ in infants born to mothers with preeclampsia and those infants with culture-proven sepsis. METHODS: Serial serum samples (N = 95) were obtained from 27 infants less than 33 weeks' gestation. Samples were analyzed for TPO using enzyme-linked immunosorbent assay. All samples had an accompanying complete blood count. Analysis of variance with post hoc analysis by least significant difference test, Mann-Whitney test, or chi2 was used to compare groups, as appropriate. Forward, stepwise linear regression was used to account for potential confounding variables. Data are expressed as mean +/- SD. RESULTS: TPO levels were not significantly correlated with the absolute platelet counts (R = -0.04, P = 0.69). TPO levels were significantly correlated with gestational age (R= 0.50, P < 0.001) when the platelet count was less than 150,000/mm3. TPO levels were significantly elevated in infants with platelets less than 150,000/mm3 born to mothers with preeclampsia compared with infants with sepsis (1184 +/- 98 vs. 579 +/- 363 pg/mL, P < 0.01). After adjusting for confounding variables using multivariate analysis (model: r2 = 0.43, P < 0.01), gestational age (r2 = 0.26) and preeclampsia (r2 = 0.03) remained significantly associated with TPO levels, whereas sepsis did not contribute to the variability of TPO. CONCLUSIONS: TPO response of infants with platelets less than 150,000/mm3 is dependent on gestational age. Infants with thrombocytopenia associated with preeclampsia have increased circulating levels of TPO. Infants with thrombocytopenia secondary to sepsis do not show an increase in TPO, but this appears to be an effect of low gestational age.     

特发性血小板减少性紫癜实验室特点与临床意义

目的 研究特发性血小板减少性紫癜实验特点与临床诊断、治疗效果的关系。方法对57例ITP患儿和15例健康儿童进行血小板计数(BPC)、平均血小板体积(MPV)、血小板分布宽度(PDW)和血小板压积(PCT)测定;对57例ITP患儿用酶联免疫法(ELISA)检测血小板相关抗体(PAIgG、PAIgM);用聚合酶链反应(PCR)检测VB19、EBV、CMV;42例患儿接受地塞米松联合丙种球蛋白治疗。结果①治疗前,ITP组的BPC、PCT明显降低,与对照组比较有统计学意义(P<0.05),急性ITP(AITP)的PDW、MPV明显增加(P<0.05),慢性ITP(CITP)组PDW、MPV无明显变化(P>0.05)。②治疗后,AITP组PDW、MPV与对照组比较无明显变化(P>0.05);CITP组BPC、PCT仍明显减少,MPV呈明显增大(P<0.05),PDW呈分布宽度差异性变大。③丙种球蛋白治疗效果与血小板相关抗体(PAIgG、PAIgM)的表达有统计学意(X2值分别为5.03、3.96,P<0.05)。结论 血小板参数可作为ITP的诊断、病情严重程度的判别指标;血小板相关抗体PAIgG和PAIgM的表达对于指导丙种球蛋白临床治疗有一定的意义。     

Platelet-Associated IgG in Children - Values and Evaluation of PAIgG in Various Thrombocytopenias -

Platelet-associated IgG (PAIgG) levels were measured in 60 children with ITP (46-chronic, 14-acute) using Fab-anti Fab radioimmunoassay method described by McMillan et al. In some patients platelet binding IgG in serum (PBIgG) was also determined at the same time. Patients with ITP had significantly greater PAIgG levels than 30 normal subjects and 13 non-immune thrombocytopenic controls. Elevated PAIgG values did not correlate with parameters of platelet size (mean platelet volume; MPV and percentage of large platelet; PLP) and so these data indicated that high levels of PAIgG in ITP were not due to nonspecific adhesion of serum IgG to megathrombocytes usually increased in this disorder, but due to specific immunological reaction. PBIgG IgG values were also elevated in patients with pretreated chronic ITP, but high levels remained even after successful splenectomy. Furthermore, serial determination of PAIgG values were obtained in some patients with chronic ITP who underwent splenectomy and with acute ITP who achieved spontaneous remission. PAIgG returned to normal levels when thrombocytopenia disappeared. PAIgG seems to be the most reproducible indicator which reflects transition of the clinical picture in this disorder.     

骨髓TPO与TGF-β1、TGF-βRⅢ的改变及其相关性在儿童ITP发病中的意义

目的 　探讨骨髓内环境中的血小板生成素 (TPO)、转化生长因子 β1 (TGF -β1 )及巨核细胞中转化生长因子 β1 的Ⅲ型受体 (TGF -βRⅢ )在儿童特发性血小板减少性紫癜 (ITP)发病中的意义。方法 　收集 2 8例急性ITP(AITP)患儿、16例慢性ITP(CITP)患儿和 2 0例相对正常儿童的骨髓 ;用Percoll密度梯度及免疫磁珠法分离骨髓巨核细胞 ;采用双抗体夹心ABC -ELISA法检测TPO、TGF -β1 水平 ;采用原位杂交法检测TGF -βRⅢ的表达情况。结果 　①AITP组与CITP组骨髓TPO的水平均高于对照组 ,且CITP组明显高于AITP组 (P <0 .0 5 ) ,但三组之间无显著差异 (P >0 .0 5 ) ;②AITP组与CITP组骨髓TGF -β1 的水平及巨核细胞TGF -βRⅢ的表达均明显高于对照组 (P <0 .0 5 ) ,且CITP组明显高于AITP组 (P <0 .0 5 ) ,三组之间有显著差异 (P <0 .0 5 ) ;③除CITP组骨髓TPO与TGF -β1 的水平呈正相关关系外 (r =0 .65 3 ,P <0 0 5 ) ,其余两组均无明显相关性 (P >0 .0 5 )。结论 　检测ITP患儿骨髓TPO、TGF -β1的水平及巨核细胞TGF -βRⅢ的表达情况对于研究ITP的发病机制以及早期分型和判断预后有重要参考价值。     

Misdiagnosis of chronic thrombocytopenia in childhood

PURPOSE: Children ultimately diagnosed with nonimmune chronic thrombocytopenia are often referred to pediatric hematology clinics with a provisional diagnosis of autoimmune thrombocytopenic purpura (AITP). The authors' aim was to establish in these patients the features characterizing the mechanism of thrombocytopenia. PATIENTS AND METHODS: The authors performed a retrospective review of the case records of seven children (three boys and four girls, aged 5 months to 7 years) with misdiagnosed chronic AITP referred to a single pediatric hematology center between 1990 and 2000. RESULTS: In the seven children, the suspected diagnosis on referral was AITP and the final diagnosis was inherited thrombocytopenia. Abnormalities of platelets and/or leukocyte morphology were present in all of them. Other features suggestive of inherited thrombocytopenia included a history of familial thrombocytopenia (2/7), failure of steroids and/or intravenous immunoglobulins to raise the platelet count to normal levels (5/7), and moderate increase of Indium-111 platelet turnover in the two patients tested. Platelet-associated IgG (PaIgG) was above the normal threshold in the four children tested; the direct monoclonal antibody immobilization of platelet antigens (MAIPA) test was negative in the four children tested and the serum test was positive in two boys. Bone marrow examination revealed either a normal (4/7) or an elevated (3/7) number of megakaryocytes. CONCLUSIONS: Family history and blood cell morphology analysis in experienced hands are the first steps in discriminating AITP from inherited thrombocytopenia in children with isolated chronic thrombocytopenia. In contrast, bone marrow examination and search for specific autoantibodies using the MAIPA test are of little help. An isotopic platelet life span study, when available, should be performed before considering splenectomy to exclude the diagnosis of inherited thrombocytopenia, especially when steroids and/or IgG IV administration failed to raise the platelet count.     

Prognostic implications for direct platelet-associated IgG in childhood idiopathic thrombocytopenic purpura

To determine the value of the direct platelet associated IgG (PAIgG) level as a prognostic indicator in childhood idiopathic thrombocytopenia purpura (ITP), 18 children with ITP were studied. Ten of the 18 had PAIgG levels measured at diagnosis, before any therapy. Of these 10 patients, six (Group I) had an acute course, with a mean initial platelet count of 15 X 10(9)/liter and a mean initial PAIgG level of 330.9 fg/plt. Four patients (Group II) had a chronic course, with a mean initial platelet count of 11 X 10(9)/liter and a mean initial PAIgG level of 38.3 fg/plt. There was no significant difference between the mean initial platelet count of Groups I and II (p greater than 0.10), but the initial PAIgG levels in those patients with an acute course were significantly higher than the levels in those patients with a chronic course (p less than 0.05). Of the original 18 patients, nine were splenectomized for chronic thrombocytopenia, with normalization of the platelet count in all instances. Of these splenectomized patients, five had platelet counts and PAIgG levels measured before and after splenectomy. All five had normal PAIgG levels following splenectomy. The PAIgG level is a good prognostic indicator for the clinical course of childhood ITP. A high PAIgG level suggests an acute course while a modestly elevated level suggests a chronic course. The PAIgG level normalizes in remission after splenectomy.     

Evaluation of a simple immunodiffusion technique for quantitation of platelet-associated immunoglobulin G in childhood immune thrombocytopenias

Platelet-associated IgG (PAIgG) was quantitated in 33 children with immune thrombocytopenia and platelet counts less than 100 X 10(9)/liter using a simple radial immunodiffusion (RID) assay. Elevated PAIgG levels were found in 76% (16/21) of children with acute idiopathic thrombocytopenic purpura (ITP), 88% (7/8) of children with chronic ITP, and all four children studied with systemic lupus erythematosus and thrombocytopenia. Normal PAIgG values were found in children with the following disorders: malignancy and chemotherapy-related thrombocytopenia; ITP in remission (platelet counts greater than 150 X 10(9)/liter); various nonimmune hematologic disorders and juvenile rheumatoid arthritis, these children having normal platelet counts. In children with acute ITP, elevated PAIgG values at initial presentation fell to within the normal range when clinical remission occurred. The RID assay can be easily established in most hematology laboratories and has the advantage that solubilized "test" platelets used in the assay can be stored frozen prior to analysis. We conclude that this simple technique is of value in the evaluation of childhood thrombocytopenic states and yields results comparable to those reported using more complex antiplatelet antibody assays.     

Platelet-Associated IgG in Pediatric HIV Infection

Hematologic abnormalities, including thrombocytopenia, are seen in HIV infection. Mi have previously reported elevated platelet-associated IgG (PAIgG) in thrombocytopenia in children associated with human immunodeficiency virus (HIV). In this study we prospectively monitored 40 HIV-infected infants and children to determine the significance of elevated PAIgG levels as they relate to thrombocytopenia. We also examined platelet eluatesfor the presence of HIV antibody and antigen. Of 16 patients with thrombocytopenia, 15 (93.7%) had elevated PAIgG. Of 24 patients with normal platelet counts, 21 (87.5%) had elevated PAIgG. On follow-up, none of the children with normal platelet counts and elevated PAIgG levels developed thrombocytopenia. Examination of the platelet eluates was negative for HIV antibody or P24 antigen. Although the sensitivity of an elevated PAIgG level in predicting thrombocytopenia is 93%, its specificity is only 13%. Elevated PAIgG levels are therefore not causally related to the development of thrombocytopenia in children.     

Immunobiology of T helper cells and antigen-presenting cells in autoimmune thrombocytopenic purpura (ITP)

Autoimmune thrombocytopenic purpura (AITP) is a bleeding disease in which autoantibodies are directed against the individual's own platelets, resulting in enhanced Fc-mediated platelet destruction by macrophages in the reticuloendothelial system. Most research in AITP has focused on characterization of the autoantibodies, while little has been devoted to the cellular immune mechanisms leading to autoantibody production. This report summarizes the current state of the literature and argues that enhanced T helper cell/antigen-presenting cell interactions in patients with AITP are the primary stimulus for the development of antiplatelet autoantibody production. Understanding these events is important for eventually identifying disease-initiating platelet autoantigens and ultimately developing specific immunotherapies for AITP.     

Platelet antibody in prolonged remission of childhood idiopathic thrombocytopenic purpura

Evaluations were performed in 20 patients with childhood idiopathic thrombocytopenic purpura (ITP) who remained in remission longer than 12 months. The mean duration of follow-up from diagnosis was 39 months (range 17 to 87 months). Eleven patients (four girls) in group 1 had an acute course of ITP, defined as platelet count greater than 150 X 10(9)/L within 6 months of diagnosis. Nine patients (five girls) in group 2 had a chronic course, defined as platelet count less than 150 X 10(9)/L for greater than or equal to 1 year or requiring splenectomy in an attempt to control hemorrhagic symptoms. Mean age at diagnosis and duration of follow-up were similar for both groups. Platelet count and serum (indirect) platelet-associated IgG (PAIgG) levels were normal in all 20 patients at follow-up. Both direct and indirect PAIgG levels were measured using a 125I-monoclonal anti-IgG antiglobulin assay. All had normal direct PAIgG levels, except for one patient in group 1 who had a borderline elevated value of 1209 molecules per platelet. These data suggest that the prevalence of elevated platelet antibodies is low during sustained remission without medication in patients with a history of childhood ITP. These data may be relevant for pregnant women with a history of childhood ITP, with regard to the risk of delivering an infant with thrombocytopenia secondary to transplacental passage of maternal platelet antibody.