特发性血小板减少性紫癜患者血小板相关抗体及网织血小板检测的临床意义

目的探讨血小板相关抗体(PAIgG)和网织血小板(RP)检测在特发性血小板减少性紫癜(ITP)治疗中的临床意义。方法收集常州市第一人民医院2003-06～2004-10住院的ITP患者48例,根据疗效分为两组,其中临床有效组40例,临床无效组8例,以50例健康人为正常对照。应用流式细胞仪(FCM)测定其治疗前后血浆和(或)血清PAIgG及RP%,并常规血小板计数。结果ITP患者临床有效组治疗后较治疗前血小板计数明显升高、PAIgG和RP%显著降低(P<0.01)。临床无效组治疗前后血小板计数、PAIgG和RP均无明显变化(P>0.05)。两组治疗前3项指标与对照组比较差异有显著性意义(P<0.01)。结论PAIgG和RP动态检测将是ITP患者血小板治疗效果的预测指标之一。     

特发性血小板减少性紫癜患者血小板抗体等四项参数测定的价值

目的　探讨特发性血小板减少性紫癜 (ITP)患者血小板抗体 (PAIgG)、血小板膜蛋白(CD62P)、网织血小板 (RP)及淋巴细胞亚群变化及意义。方法　应用流式细胞术检测 5 8例ITP组及 2 0例正常对照组外周PAIgG、血CD62P、RP、淋巴细胞亚群的表达。结果　ITP组的血小板数明显低于正常对照组 (P <0 .0 1) ,PAIgG、CD62P、RP均明显高于正常对照组 (P <0 .0 1)。在淋巴细胞亚群中 ,ITP组CD3、CD4、CD4/CD8比值明显低于正常对照组 (P <0 .0 1) ,CD8、CD19细胞则显著高于正常对照组 ,而CD16+ 5 6与正常对照组无明显差异。结论　PAIgG、CD62P、RP及淋巴细胞亚群的变化可较好地反映ITP这一病理过程 ,对提高诊断水平及指导临床有一定实用价值。     

特发性血小板减少性紫癜的体液免疫机制

现代体液免疫学观点认为 ,特发性血小板减少性紫癜(ITP)的发生主要由自身抗体介导。自身抗体致敏的血小板通过巨噬细胞表面的Fcγ受体在脾脏等部位加速清除[1] 。笔者就近年来ITP体液免疫机制的重要研究进展加以综述。1 血小板相关抗体 :1975年 ,Dixon等[2 ] 首次用定量方法检测了血小板表面的免疫球蛋白 ,称其为血小板相关IgG(PAIgG)。此后国内外各种免疫检测方法均证明 :大多数ITP患者的PAIgG水平升高 ,PAIgG与血小板计数、血小板寿命间呈负相关 ,与血小板大小呈正相关。大量资料同时显示PAIgG升高对ITP并非特异 ,还可见于继…     

特发性血小板减少性紫癜患者PAC-1、CD62P、PAIgG检测及意义

采用流式细胞仪测定特发性血小板减少性紫癜(ITP)、非免疫性血小板减少、其他自身免疫性疾病患者及健康查体者的血小板相关抗体(PAIgG)、血小板膜糖蛋白b-a(PAC-1)、血小板α颗粒膜糖蛋白(CD62P)的表达情况。结果ITP患者PAC-1阳性表达率明显高于其他三组(P<0.01),PAIgG阳性血小板百分率与平均荧光强度(MFI)综合统计对ITP患者阳性诊断率为84.4%;无临床症状ITP患者的PAC-1表达率明显高于有临床症状者。提示PAIgG对ITP诊断具有较高的阳性率,结合PAC-1可提高ITP的诊断率;PAC-1可作为ITP患者疗效及判断预后的指标。     

特发性血小板减少性紫癜患者血小板相关抗体水平与预后的关系

目的:探讨特发性血小板减少性紫癜(ITP)与血小板相关抗体之间的相互关系,为临床诊断和治疗提供帮助。方法:回顾性分析了2000年1月～2007年4月应用流式细胞术检测140例临床确诊的ITP患者初诊时及治疗前后不同血小板相关抗体——血小板膜糖蛋白抗体(PAIg)的表达。结果:ITP患者初诊时PAIgG、PAIgA及PAIgM抗体表达水平均高于正常对照组;PAIgG、PAIgM、PAIgA表达水平与血小板数之间均呈负相关,相关系数分别为γ=-0.72、γ=-0.83和γ=-0.67。在确诊ITP后予激素等免疫治疗无效转变为慢性ITP的患者时,PAIgM抗体水平要明显高于激素治疗有效的急性ITP患者,并且PAIgM异常增高或联合PAIgG增高的比例要显著多于急性ITP患者(均P<0.05)。35例PAIgG和PAIgM同时升高的ITP患者,经治疗血小板升至正常后,PAIgG、PAIgM抗体表达水平均有显著下降。结论:ITP的发生与血小板抗体密切相关,初诊ITP患者PAIgM单独或联合PAIgG异常增高常提示预后不良,易转变为慢性ITP。     

流式细胞术研究特发性血小板减少性紫癜患者血小板相关抗体

目的：探讨特发性血小板减少性紫癜（ITP）患者血小板表面相关抗体（PAIg）在诊断及预后的价值。方法：应用流式细胞术（FCM）检测84例ITP患者及20例正常人PAIgG、PAIgM、PAIgA。结果：初发ITP和复发ITP患者组与正常对照组比较，PAIgG、PAIgA差异有统计学意义（P〈0．01），PAIgM差异无统计学意义（P〉0．05）。PAIgM与PAIgA之间有显著相关性，r=0．451（P〈0．01）。结论：①PAIg增高可作为诊断初发ITP的重要指标之一；②FCM检测ITP患者血小板表面PAIg敏感性好、特异性高，适用于临床，对ITP的诊断及预后评价有较好的实用价值；③初发型ITP患者以PAIgG和PAIgA增高为主，预后较好；复发型以PAIgM增高为主，预后较差，易复发。     

ITP患者脾脏、骨髓的病理变化及其与PAIgG的关系

目前公认原发性血小板减少紫癜(ITP)是由于自身免疫功能紊乱引起,特别是与血小板相关抗体(PAIgG)分泌增多有关.本研究对ITP患者的骨髓、脾脏病理变化及与PAIgG的关系进行了研究.现报告如下.     

γ-干扰素和白细胞介素-4在特发性血小板减少性紫癜发病机制中的作用

目的　探讨γ 干扰素 (IFN γ)和白细胞介素 4(IL 4)在特发性血小板减少性紫癜发病中作用。方法　用ELISA方法 ,检测IL 4,IFN γ ,PAIgG在特发性血小板减少性紫癜 (ITP)治疗前后的变化情况。结果　ITP患者治疗前IL 4明显高于对照组 ,治疗达到缓解后 ,IL 4明显下降 ,P <0 .0 5 ,而未缓解组 ,IL 4未见明显变化。治疗前的IFN γ与对照组相比。虽有增加 ,但差异无显著性 (P >0 .0 5 )。结论　IL 4,IFN γ对ITP患者Th1/Th2应答及临床相关性起着一个重要调节作用。     

血浆置换与血小板洗涤对ITP患者血小板及相关抗体影响的研究

目的：探讨血浆置换（PE）和血小板洗涤（PW）对特发性血小板减少性紫癜（ITP）患者体内血小板相关抗体（PAIg）水平及血小板计数（BPC）变化的影响。方法：对各组测定PAIg和BPC的变化并作统计学处理比较。结果：PE加PW治疗组PAIg含量的递减速度均明显快于普通治疗组（P〈0．01）,普通治疗组BPC的回升速度明显慢于PE加PW组（P〈0．01）。结论：血浆置换及血小板洗涤治疗ITP可迅速降低患者体内PAIg水平、促进体内BPC的回升;BPC的回升与PAIg水平的递减呈负相关,动态监测PAIg和BPC的变化有助于及时评估患者病情转归情况和指导临床治疗方案。     

特发性血小板减少性紫癜患者外周血淋巴细胞亚群和血小板相关抗体变化及临床意义

用流式细胞术直接免疫法检测l72例早期特发性血小板减少性紫癜(ITP)患者外周血淋巴细胞亚群(CD3、CD4、CD8、CD19、C16、CD56)，ELISA法检测血小板表面血小板相关抗体(PAIgG、PAIgA、PAIgM)。结果显示，ITP组与正常对照组比较CD3、CD4／CD8显著降低(P＜0.01)，CD8增高(P＜0．05)，CD19增高极为显著(P＜0．01)；ITP血小板表面PAIgG、PAIgA、PAIgM显著高于对照组；CD19升高和CD4/CD8下降与PAIgG、PAIgA、PAIgM增高有显著的相关性。认为淋巴细胞亚群功能和比例失常、T细胞免疫调节机制紊乱在ITP的发病机制中起非常重要的作用。     

Platelet associated IgG, platelet survival, and platelet sequestration in thrombocytopenic states

S ummary . Platelet-associated IgG (PAIgG), platelet mean life span (MLS), and platelet sequestration sites were studied in 69 patients with immune (ITP) and presumed nonimmune thrombocytopenias (NTP). A shortened MLS was associated with elevated PAIgG (N=46), and with normal PAIgG (N=15), Four patients had a normal MLS, but elevated PAIgG, four patients were normal for both parameters. The highest PAIgG values occurred in ITP patients with a very short MLS. Nine NTP patients had also elevated PAIgG, but a normal or slightly shortened MLS. There was a significant double log correlation between PAIgG and MLS for ITP, but not for NTP patients. Judged from the coefficient of determination, only 10% of PAIgG were directly related to a shortened MLS.
70% of patients (N= 63) had exclusively splenic and 30% hepatosplenic sequestration. PAIgG was elevated in 29/44 patients with splenic (66%) and in 16/19 patients with hepatosplenic sequestration (84%). In ITP, PAIgG-positive cases were observed in 69% of splenic v 82% of hepatosplenic sequestration, while in NTP the corresponding figures were 6/11 and 2/2. No significant correlation between PAIgG and either sequestration type was demonstrable.
We conclude that in immunologically mediated thrombocytopenia only a small portion of PAIgG accounts for a decreased MLS, and that the concentration of PAIgG per se does not determine the platelet sequestration type.     

Comparison of the measurement of surface or total platelet-associated IgG in the diagnosis of immune thrombocytopenia

Platelet-associated IgG (PAIgG) can be measured on intact platelets or following platelet lysis. Measurement of PAIgG following platelet lysis may provide different or additional information compared to PAIgG measured on intact platelets. The PAIgG of lysed platelets represents "total" PAIgG, ie, IgG on the surface of platelets plus any IgG that was inside the platelet. To investigate the clinical relevance of the two types of PAIgG assay we performed a prospective study on washed platelets collected from 47 patients with idiopathic thrombocytopenic purpura (ITP). The PAIgG was measured on intact and lysed platelets using an immunoradiometric assay. Platelet-associated IgG was 2-3 times higher when measured on lysed platelets from healthy controls or patients with ITP compared to PAIgG measured on the same intact platelets. The higher level of PAIgG observed following platelet lysis was not due to the reactions not achieving equilibrium. Using lysed platelets, PAIgG was elevated on 29 of 47 samples from different ITP patients and elevated in 31 samples when measured on intact platelets. The PAIgG is invariably higher when measured following platelet lysis compared measurements made on intact platelets. Neither technique offers a diagnostic advantage over the other.     

The Clinical Significance of Platelet-Associated IgG: a Study on 298 Patients with Various Disorders

S ummary . Platelet-associated IgG (PAIgG) was studied by a quantitative platelet radioactive anti-IgG test (PRAT) in 298 patients. At the time of investigation, 171 patients were thrombocytopenic (platelet count <100 × 10⁹/1), 127 had normal platelet counts. Patients fell into the following disease categories: Idiopathic thrombocytopenic purpura (ITP) ( N =81), possible ITP (19), acute ITP (9), systemic lupus erythematosus (22), autoimmune haemolytic anaemia of warm-type (18), systemic blood disease (65), liver diseases (35), others (49). A significant elevation of PAIgG was found in all disease categories. There was a significant correlation between PAIgG and the reciprocal values of platelet counts for most disease groups. No relationship was discernible between PAIgG and hypergammaglobulinaemic states (serum IgG >1.8 g/l), Platelet survival studies ( N=30 ) revealed that normal and increased values of PAIgG were associated with normal or shortened platelet mean life span. It is concluded that an elevated PAIgG is only one of several factors involved in the development of immunologically mediated thrombocytopenia.     

Immune thrombocytopenic purpura: autoimmune or immune complex disease?

To assess the pathogenic role of circulating immune complexes (CIC) in idiopathic thrombocytopenic purpura (ITP), 39 patients with ITP were compared to 17 patients with other forms of thrombocytopenia (hypersplenism (N = 12), impaired thrombopoiesis (3), thrombocytopenia of unknown origin (2)) and six nonthrombocytopenic subjects. In all patients, platelet mean life span (MLS), platelet associated IgG (PAIgG), as well as circulating anti-platelet antibodies and C1q binding activities were determined. In most cases, immune complex solubilization capacity (ICSC) and immune complex precipitation inhibition capacity (ICPIC) of sera were also assessed. All patients with ITP had a reduced platelet MLS, but PAIgG was elevated in only 16 out of 24 patients with chronic ITP, in six out of 10 patients with acute ITP and in four out of five patients with secondary ITP. In the group of patients with thrombocytopenia due to splenomegaly, seven out of 12 patients had elevated PAIgG while the platelet MLS was only slightly reduced. Of the 39 patients with ITP only one with secondary ITP had C1q binding material in his serum, as opposed to six out of 12 thrombocytopenic patients with splenomegaly. Whereas only three patients with ITP had abnormal immune-complex modulating capacities, such deviations were found in seven out of 12 patients with thrombocytopenia due to splenomegaly. We conclude that our data render the role of CIC in the pathogenesis of ITP very questionable.     

特发性血小板减少性紫癜与幽门螺杆菌感染的相关性研究

目的研究特发性血小板减少性紫癜(ITP)与幽门螺杆菌(Hp)感染的相关性,观察抗Hp治疗对难治性ITP的疗效。方法对中国医科大学附属第一医院血液科2002年11月至2005年5月收治的48例ITP患者进行研究,正常对照组52例,因消化系统症状行胃镜和其他相关检查但未见明显异常的门诊患者。采用13C-尿素呼气试验及Hp血清抗体联合诊断Hp感染。对11例Hp感染阳性的难治性ITP患者抗Hp治疗,采用经典的三联药物,具体为奥美拉唑20mg口服,每日2次;克拉霉素500mg口服,每日2次;阿莫西林1g口服,每日2次,连用7d,4~8周后复查13C-尿素呼气试验、Hp血清抗体、血小板计数和血小板抗体。结果ITP组和正常对照组的Hp感染阳性率分别为68.18%(33/48),46.12%(24/52),ITP组Hp阳性率显著升高(P<0.05);11例常规治疗无效或复发患者并伴有Hp感染,有8例经上述治疗Hp感染转为阴性,该8例4~8周后血小板计数显著升高,其中6例血小板自身抗体消失,而Hp检测阴性患者和Hp感染未得以根治的患者随访时血小板抗体和血小板计数均无变化。结论ITP患者Hp感染阳性率高于正常人;对于Hp感染阳性的难治性ITP患者,根除Hp的方法治疗ITP是行之有效的。     

Antiplatelet antibodies and their correlation with clinical findings in childhood immune thrombocytopenic purpura

The demonstration of antiplatelet antibodies (PAIgG, PAIgM) and decreased detection of platelet surface antigens (CD41, CD61, CD42b) in children with immune thrombocytopenic purpura (ITP) have a diagnostic role. This study was conducted to determine whether these parameters differed in acute and chronic ITP. Chronic ITP was defined as thrombocytopenia persisting for more than 6 months from the onset of illness. A total of 80 subjects were divided into three groups: group 1 included 39 patients with acute ITP; group 2 included 31 patients with chronic ITP, and group 3 included 10 healthy children. At diagnosis, blood samples were obtained for platelet count, mean platelet volume, plateletcrit and platelet distribution width along with platelet surface antigens and antiplatelet immunoglobulins. We found that platelet surface antigens were significantly decreased in both acute and chronic ITP when compared to the control group (p = 0.001). In contrast, PAIgG was increased in acute and chronic ITP patients compared to the control group. PAIgM was significantly higher in acute ITP. We conclude that decreased platelet surface antigens and increased antiplatelet antibodies are observed in both acute and chronic ITP. In patients with chronic progress, a relatively lower level of PAIgM can be identified.     

血小板自身抗体的流式细胞仪检测与意义

目的：应用流式细胞术（ＦＣＭ）测定血小板自身抗体ＰＡＩｇＧ,研究其对待发性血小板减少性紫癜（ＩＴＰ）诊断的意义。方法：应用ＦＣＭ检测２０例ＩＴＰ患者血小板膜表面及血浆中的抗血小板抗体,并与ＥＬＩＳＡ所测结果进行比较。结果：ＦＣＭ测得１４例（７０％ＩＴＰ患者血小板膜自身抗体ＰＡＩｇＧ阳性,９例（４５％）血浆抗血小板抗体阳性。ＥＬＩＳＡ显示１２例（６０％）患者ＰＡＩｇＧ阳性,７例（３５％）血浆抗血小板     

Platelet-associated IgG in immune thrombocytopenic purpura

A method for the measurement of immunoglobulin G associated with gel- filtered platelets is described and finding in 70 control subjects and 37 patients with immune thrombocytopenic purpura (ITP) are reported. Control platelet-associated IgG (PAIgG) levels (nanograms IgG per 10(9) platelets) averaged (+/-SD) 1231+/-424; samples studied after 24 and 48 hr remained within the control range. PAIgG values of 19 adult and 12 childhood patients with chronic ITP averaged 4711+/-3025 and 4923+/- 3955, respectively, and differed significantly from controls (p less than 0.001). There was an inverse correlation between PAIgG values and the chronic ITP patient's platelet count. Six patients with childhood acute ITP had PAIgG levels ranging from 5588 to 56,250 and appeared to represent a different statistical population from those with chronic ITP. In chronic ITP patients responding to splenectomy, there was an immediate normalization of PAIgG levels; however, a certain percentage of patients studied several months after splenectomy evidenced elevated PAIgG levels in association with normal platelet counts. These data showed that the direct measurement of platelet associated antibody is a useful technique in the diagnosis and follow-up of patients with chronic ITP. Preliminary studies in patients with acute ITP have suggested that this method may be useful in differentiating acute and chronic childhood ITP.     

Quantification of platelet-associated IgG with competitive solid-phase enzyme immunoassay

In order to measure platelet-associated IgG (PAIgG), we devised a solid-phase enzyme immunoassay employing a competitive binding of peroxidase-conjugated anti-IgG antiserum between platelets and polystyrene tubes coated with IgG. The amounts of peroxidase bound to the tubes were measured in a spectrophotometer by an enzymatic reaction. This method is highly sensitive, reproducible and can be carried out more simply. the PAIgG values of normal controls averaged 21.6 +/- 6.6 (SD) ng/10(7) platelets. 27 (93%) of 29 patients with idiopathic thrombocytopenic purpura (ITP), who had a platelet count of less than 15 X 10(4)/microliter, had PAIgG values greater than those of controls by 2 SD and averaged 205.5 +/- 323 ng. There was a significant inverse correlation between platelet count and PAIgG value of ITP patients. the PAIgG values of patients with aplastic anemia were within normal range.     

Quantitation of platelet-associated IgG by radial immunodiffusion

Platelet-associated IgG (PAIgG) was measured by a simple radial immunodiffusion technique using washed solubilized platelets and commercially available immunoplates. Subjects with normal platelet counts had PAIgG levels of 1.5--7.0 fg/platelet. Subjects with idiopathic immune thrombocytopenic purpura (ITP) had levels ranging from 5.7 to 70.5 fg/platelet. All patients with recurrent ITP and 85% of patients with acute ITP had elevated PAIgg. Elevated PAIgG was also found in 17% of patients with recovered ITP, 40% of patients with SLE and thrombocytopenia, 57% of patients with thrombocytopenia occurring during the course of septicemia, and 100% of patients with IgG myeloma in whom the serum IgG level was clearly elevated, regardless of the platelet count. The results are similar to reports that used more complex techniques.