The relevance of a bank with genotyped platelets donors

ABSTRACT Objective: Describe the clinical and laboratory characteristics and the transfusion strategy of patients at Hospital Israelita Albert Einstein with platelet refractoriness and identify their etiological characteristics. Standardize the platelet immunofluorescence technique by flow cytometry as a test for platelet compatibility in immune platelet refractoriness in transfusion support. Methods: Review of medical records of refractory platelet patients followed at HIAE from January 2011 to May 2017. Clinical-demographic data, laboratory data and identification of the use of compatible genotyped platelets for patients in need of transfusion therapy were collected. The analyzed patients were classified according to the etiology of their platelet refractoriness. To standardize the FC-PIFT technique, blood group O platelets were incubated with serum from blood group AB donors and anti-IgG monoclonal antibody to determine the negative control. In order to verify the influence of the ABO system, monoclonal anti-IgG antibodies were incubated with blood group A or B platelets and with blood group O donor serum with isohemagglutinins below and above 1/64. Results: A total of 47 patients were evaluated, a 51% (24/47) preponderance of associated immune and non-immune factors (NIPR + IPR). The most common causes of NIPR + IPR were splenomegaly (54%) and the development of HLA antibodies (88%), consistent with the literature. For patients who required therapeutic transfusion, only a small portion received compatible genotyped platelets. Conclusion: Although 60% of patients could benefit from the therapeutic transfusion of genotyped platelets, only 10% were actually transfused with this type of blood component. This reaffirms the need for investments in a bank of genotyped platelet donors.

Platelet antibodies identification: comparison between two laboratory tests

ABSTRACT Introduction: Platelet antibody identification is indispensable for diagnosing the human platelet antigen (HPA) or human leukocyte antigen (HLA) immunization, mostly because it can restrict the compatibility and results of transfusions. Correct detection of these antibodies is of utmost importance for the diagnosis and treatment. Method: We present 16 platelet alloimmunization results, comparing two tests with different technologies: the MAIPA (monoclonal antibody immobilization of platelet antigens), as a reference technique, and a bead-based assay, the Pak-Lx. Results: Eleven samples (68.75%) showed agreement in both techniques. Two tests were false negatives in the Pak-Lx: a pan-reactivity in GPIIbIIIa and an anti-HPA-9b. On the other hand, the Pak-Lx was more sensitive to detect a decreasing anti-HPA-5b. The Pak-Lx found an anti-HPA-2b positive, but with a low median fluorescent intensity (MFI), suggesting a false-positive result. Moreover, in one case, the MAIPA was negative for a positive Pak-Lx HLA. Conclusion: Antibody platelet diagnosis can sometimes be challenging. The methods seemed similar, the Pak-Lx being faster and simpler than the MAIPA, and they can be complementary to solve clinical issues.

Identification of a rare platelet-specific antigen HPA-10bw allele among ethnic Han Chinese population in Shandong / 中华医学遗传学杂志

OBJECTIVE@#To study the polymorphism of human platelet antigen (HPA) system 10 among ethnic Han Chinese from Shandong, China so as to supplement the data of platelet donor bank in the region.@*METHODS@#Peripheral blood samples of platelet donors from the region were genotyped for HPA-10 alleles by PCR-sequence specific primer (PCR-SSP) and direct sequencing.@*RESULTS@#Among 1401 donors, a rare heterozygote carrier of HPA-10w (a+b+) was identified, which gave an allelic frequency of approximately 0.035%.@*CONCLUSION@#The detection of rare HPA-10bw antigen allele among ethnic Han Chinese from Shandong is useful for the diagnosis and prevention of neonatal alloimmune thrombocytopenia and post-transfusion purpura in the region.

Establishment of Quantitative SPR Assay for Antibodies Against Human Platelet Antigen-1a / 中国实验血液学杂志

OBJECTIVE@#To establish quantitative surface plasmon resonance (SPR) assay for antibodies against human platelet antigen-1a (HPA-1a).@*METHODS@#Recombinant protein was fixed on the chip surface by amino coupling method. SPR assay was used to detect the standard antibodies against HPA-1a at different conceatration. The optimal experimental parameters were determined, and standard curves were constructed with linear regression. Moreover, the sensitivity, specificity, accuracy and precision of the assay were evaluated.@*RESULTS@#The quantitative SPR assay for HPA-1a antibodies was established. The determination ranges were 0-20 IU, with accuracy (recovery rate) was 97.75%-103.08%. The intra-assay precision [coefficients of variation (CV)] was 3.53%-4.29%, and the inter-assay precision (CV) was 2.08%-4.40%. For specificity test, several kinds of monoclonal and human antibodies against platelet membrane protein were tested and no positive result was observed.@*CONCLUSION@#The established quantitative SPR assay for HPA-1a antibodies shows good sensitivity, specificity, accuracy and precision, and this rapid and simple method provides a new reference method for scientific research and clinical antibody detection.

Platelet HPA Typing of Platelet Donors in Zhangjiakou Area / 中国实验血液学杂志

OBJECTIVE@#To analyze the polymorphism of the HPA1-5,15 system of the donors in Zhangjiakou area.@*METHODS@#DNA was extracted from the blood samples of the donors, PCR- SSP method was used to divide HPA1-6, 15 genotype. The gene frequency and genotype frequency were calculated, compared with the difference and regiahal specificity of the populations in our country and foregiens was compared other populations.@*RESULTS@#The gene expression in the HPA-1, HPA-2 and HPA-4 systems were all homozygous aa, and the donors who expressed homozygous bb was not exessed. Among them, one heterozygous ab expression was found in both HPA-1 and HPA-4 systems (1%), and 14 cases of heterozygous ab expression were found in HPA-2 system (14%). The gene expression in the HPA-5 system was mainly homozygous aa (98%), and a very few expressed homozygous bb (2%) was found. The degree of heterozygosity of gene expression in the HPA-3 and HPA-15 systems was relatively high. The proprotion of the expression of aa, ab and bb in the HPA-3 system was respectively 46%, 40% and 14%, the proprotion of the expression of aa, ab and bb in the HPA-15 system was respectively 21%, 64% and 15%.@*CONCLUSION@#The gene frequency of platelet-specific antigen HPA1-5,15 system in zhangjiakou region shows local characteristics. The heterozygosity degree of gene expression in the HPA-3 and HPA-15 systems are both high, suggesting that they are more likely to result in alloimmunization and ineffective platelet transfusion, which should be pays attention to.

Human platelet antigen-3 polymorphism as a risk factor for rheumatological manifestations in hepatitis C

Abstract INTRODUCTION: Hepatitis C virus (HCV) infection is involved in the pathogenesis of autoimmune and rheumatic disorders. Although the human platelet antigens (HPA) polymorphism are associated with HCV persistence, they have not been investigated in rheumatological manifestations (RM). This study focused on verifying associations between allele and genotype HPA and RM in patients with chronic hepatitis C. METHODS: Patients (159) with chronic hepatitis C of both genders were analyzed. RESULTS: Women showed association between HPA-3 polymorphisms and RM. CONCLUSIONS: An unprecedented strong association between rheumatological manifestations and HPA-3 polymorphism, possibly predisposing women to complications during the disease course, was observed.

Analysis on Polymorphism of Platelet Antigen Gene in Shandong Han Population / 中国实验血液学杂志

OBJECTIVE@#To study the Polymorphism of the human platelet antigen(HPA) gene 1-17 and human leukocyte antigen(HLA) gene-A and B locus in Shandong Han population.@*METHODS@#A total of 962 samples from routine voluntary platelet donors were genotyped for HPA1-17 system and HLA-A site, B by PCR-SSP and PCR-SSOP respectively．Gene frequencies were calculated by counting. HPA1-17 and HLA genotype combinations were analyzed by Arelequin 3.5.@*RESULTS@#The gene frequencies of HPA-la, -1b, HPA-2a, -2b, HPA-3a, -3b, HPA-4a, -4b, HPA-5a, -5b, HPA-6a, -6b, HPA-15a, -15b were 0.9918, 0.0082, 0.9419, 0.0592, 0.5841, 0.4174, 0.9969, 0.0031, 0.9892, 0.0108, 0.9835, 0.0175,0.5488 and 0.4512, respectively． The most common HPA genotype combination was HPA-(1, 2, 4, 5, 6, 7-14, 16, 17) aa-3ab-15ab (0.2048). Moreover, HLA-A*2(0.3094) and HLA-B*13(0.1513) showed the highest frequency in their respective locus. The most common HLA genotype combination was HLA-A*2-B*13(0.1397) .@*CONCLUSION@#Distributions of HPA and HLA show high polymorphism in Shandong Han population. The ethnic and territorial difference of HPA distribution is also confirmed. It is imperative to establish local genetic database of volunteer platelet donors.

Introducción del genotipaje molecular de los antigenos plaquetarios / Introduction of molecular genotypingof plateles antigens

Introducción: Los antígenos plaquetarios humanos (HPA) se expresan en 6 glucoproteínas plaquetarias diferentes. Se ha descrito que estos antígenos pueden estimular la producción de aloanticuerpos una vez expuestos a plaquetas humanas con diferentes HPA, lo que provoca complicaciones clínicas como la trombocitopenia neonatal aloinmune y la púrpura postransfusional. Métodos: Se realizó el estudio a 11 muestras de pacientes en espera de trasplante renal de genotipo de los antígenos HPA-1,2,3 a/b mediante PCR multiplex, mientras que para el estudio de genotipo de los antígenos HPA-5a/b se utilizó la técnica de PCR con secuencia específica de primer. Los productos de ADN amplificados fueron visualizados mediante electroforesis en gel de agarosa y electroforesis capilar. Resultados: El análisis de los fragmentos de ADN amplificados revelaron resultados similares por ambos métodos. Para los antígenos HPA-1,-2, el 63 por ciento de las muestras fueron homocigóticas para el fenotipo (a) mientras que se observó heterocigocidad en todos los casos para el genotipo HPA-3. En el sistema HPA-5, el 54 por ciento fueron homocigóticas para el fenotipo (a) y el 46 por ciento, heterocigóticas. Para el genotipo del HPA-15, el 4 por ciento fueron homocigóticas para el fenotipo (b) mientras que el 96 por ciento resultaron ser heterocigóticas. Conclusiones: Estos resultados muestran similitudes para los genotipos HPA 1, 2,3 a/b, HPA 5a/b y HPA15 a/brespecto a lo planteado en la literatura(AU)

Introduction: Human platelet antigens (HPA) are expressed in 6 different platelet glycoproteins. It has been described that these antigens can stimulate the production of alloantibodies once exposed to human platelets with different HPA, which causes clinical complications such as neonatal alloimmune thrombocytopenia and postransfusional purpura. Methods: The study was performed on 11 samples of patients awaiting kidney transplantation of genotype of the HPA-1,2,3 a/b antigens by multiplex PCR, while for the genotype study of the HPA-5a/b antigens was used the PCR technique with primer-specificsequence. The amplified DNA products were visualized by agarose gel electrophoresis and by capillary electrophoresis. Results: The analysis of DNA fragments amplified by agarose electrophoresis and capillary electrophoresis revealed similar results in both methods. For the HPA-1, -2 antigens, 63 percent of the samples were homozygous for phenotype (a) while heterozygosity was observed in all cases for the HPA-3 genotype. In the HPA-5 system, 54 percent were homozygous for the phenotype (a) and 46 percent were heterozygous. For the genotype of HPA-15, 4 percent were homozygous for phenotype (b) while 96 percent proved heterozygous. Conclusions: These results show similarities for the genotypes HPA 1, 2.3 a/b, HPA 5a/b and HPA15 a/bwith respect to report in literature(AU)

Anticuerpos antiplaquetarios en pacientes cubanos en espera de trasplante renal / Platelet antibodies in cuban patients waiting for renal transplantation

Introducción: Los antígenos específicos de plaquetas, conocidos como antígenos de plaquetas humanas (HPA, del inglés human platelet antigens), se incluyen dentro del espectro de antígenos de histocompatibilidad no-HLA, debido a que los anticuerpos anti-HPA participan en el rechazo del trasplante, además de ser causa del fenómeno de refractariedad plaquetaria. Objetivo: Caracterizar los anticuerpos contra antígenos específicos de plaquetas en pacientes cubanos en espera de trasplante renal. Métodos: Se investigaron muestras de sangre de 901 pacientes mediante la técnica de inmovilización de antígenos plaquetarios con anticuerpos monoclonales. Resultados: En 78 pacientes se detectaron anticuerpos anti-HPA, que en el 87,17 por ciento reconocían los antígenos presentes en el complejo GP-IIb/IIIa. Estos anticuerpos fueron del tipo IgG en el 78,2 por ciento, IgA en el 11,53 por ciento e IgM en el 46,15 por ciento. Conclusiones: En pacientes cubanos en espera de trasplante renal son frecuentes los Ac anti-HPA, en su mayoría del tipo IgG dirigidos contra antígenos presentes en el complejo GP-IIb/IIIa(AU)

Introduction: Platelet-specific antigens, known as human platelet antigens (HPA), are included within the spectrum of non-HLA histocompatibility antigens, because HPA antibodies participate in the rejection of transplantation, besides being a cause of the phenomenon of platelet refractoriness. Objective: To characterize antibodies against platelet-specific antigens in Cuban patients awaiting kidney transplantation. Methods: The technique monoclonal antibodies immobilized platelets antigens was applied to blood samples from 901 patients. Results: HPA antibodies were detected in 78 patients, which in 87.17 percent recognized the antigens present in the GP-IIb / IIIa complex. These antibodies were in 78.2 percent of the IgG class, in 11.53 percent IgA and IgM in 46.15 percent. Conclusions: HPA antibodies, mostly of the IgG class and directed to antigens present in the GP-IIb/IIIa complex, are common in Cuban patients awaiting kidney transplantation(AU)

Allele and haplotype frequencies of human platelet and leukocyte antigens in platelet donors / Frequência alélica e haplotípica dos antígenos plaquetários e leucocitários humanos em doadores de plaquetas

ABSTRACT Objective To described the allele and haplotype frequencies of human leukocyte antigen genes at the -A, -B loci and human platelet antigen genes for human platelet antigen systems 1 to 9, 11 and 15 in blood. Methods We included 867 healthy unrelated volunteer donors who donated platelets between January 2011 and December 2014. Microarray genotyping was performed using a BeadChip microarray. Medium resolution typing of the human leukocyte antigen at loci A and B was carried out using sequence-specific oligonucleotide probe hybridization. We used multivariate analysis and our human leukocyte antigen population was compared to data from the United States national bone marrow donor program. Human platelet antigen results were compared to a literature review and data from around the world. Results Our human leukocyte antigen haplotype results were more similar to those of hispanics, followed by caucasians. Likewise, our human platelet antigen sample is more similar to those of Argentina, Rio Grande do Sul and Italy. Conclusion This was the first article that discusses human platelet antigen and human leukocyte antigen data together. Rare genotypes or antibody associations can make patient management difficult. A blood bank with genotyped donors allows for optimal transfusion and can contribute to better results. Our information can serve as basis for a database of platelet antigen polymorphisms.

RESUMO Objetivo Descrever as frequências alélicas e haplotípicas de genes dos antígenos leucocitários humanos nos loci -A,- B e dos antígenos plaquetários humanos para os sistemas HPA-1 a 9, 11 e 15. Métodos Foram incluídos 867 doadores voluntários, saudáveis, não relacionados, que doaram plaquetas por aférese entre janeiro de 2011 e dezembro de 2014. A genotipagem foi realizada usando microarray BeadChip. A tipificação de resolução intermediária dos antígenos leucocitários humanos loci A e B foi realizada por meio de hibridização com sonda para oligonucleotídeos por sequência específica. Utilizamos análises multivariadas e o antígeno leucocitário humano de nossa população foi comparado com a do programa nacional de doadores de medula óssea norte-americano. Já os resultados dos antígenos plaquetários humanos foram comparados à revisão da literatura e a dados de populações de outros países. Resultados Os resultados do haplótipo de antígenos leucocitários humanos são mais parecidos com os dos hispânicos, seguidos dos caucasianos. Igualmente, a amostra de antígenos plaquetários humanos foi mais semelhante às da Argentina, do Rio Grande do Sul e da Itália. Conclusão Este foi o primeiro artigo a discutir antígenos plaquetários e leucocitários humanos simultaneamente. Genótipos raros ou associações de anticorpos podem dificultar o manejo clínico do paciente. Um banco de sangue com doadores genotipados permite um melhor resultado e transfusão possíveis. Estas informações podem servir de base para um banco de dados sobre polimorfismos de antígenos plaquetários.

HPA-1a/1b could be considered a molecular predictor of poor prognosis in chronic hepatitis C

Abstract INTRODUCTION: HPA polymorphism has been associated with HCV presence and fibrosis progression in chronic hepatitis C. However, it is unknown if there is an association between HPA-1 polymorphism and hepatocellular carcinoma (HCC). Therefore, this study aimed to evaluate HPA-1 polymorphism in the presence of HCC. METHODS: PCR-SSP was used to perform HPA genotyping on 76 HCV-infected patients. RESULTS: There was no association between patients with and without HCC. There was significant difference in HPA-1 genotypic frequency distribution between HCC and F1/F2 fibrosis degree. CONCLUSIONS: The HPA-1a/1b polymorphism appears to be more associated with liver damage progression than with HCC presence.

Anti-CD36 Mediated Platelet Transfusion Refractoriness and Related Cases After Stem Cell Transplantation / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To analyse the cases of platelet transfusion refractoriness after received HLA-matched unrelated donor hematopoietic stem cell transplantation, to analyze and identify the phenotype and genotype of CD36 in both the patient and stem cell donor, as well as the characteristic of antibody induced platelet transfusion refractoriness, and to analyse the efficacy of matched CD36-deficiency platelets transfusions.</p><p><b>METHODS</b>The CD36 expression on platelet and monocyte was analyzed by flow cytometry (FCM) in both patient and donor. Polymerase chain reaction sequence-based typing (PCR-SBT) was used to analyze the exons sequence of CD36 and HPA. Fast monoclonal antibody-specific immobilization of platelet antigen (F-MAIPA) and FCM were used to identify platelet antibodies in the patient. Short tandem repeat polymerase chain reaction (STR-PCR) was applied to monitor engraftment evidence. The platelet level was monitored. CD36- deficiency donor's platelets were selected from CD36- deficiency donor blood bank.</p><p><b>RESULTS</b>The donor was CD36 positive and the patient was typed I CD36 deficiency. The anti-CD36 antibody was identified in patient's serum (after transplantation), while the HLA and HPA-related antibodies were excluded. Sequence analysis of CD36 exon in the patient showed Exon 6 -1G>C(Change in splicing site) homozygote, which was a novel CD36 mutation. STR, HPA and CD36 of the patient (complete chimerism) were conversed to that of donor gene types on day 18 after allo-HSCT. The positive CD36 expression on platelet and monocyte in the patient was observed on day 96 after allo-HSCT. The patient showed the platelet transfusion refractoriness which was significantly improved after platelets transfusions from CD36 deficiency donors.</p><p><b>CONCLUSION</b>Stem cell transplants resulted in anti-CD36 and caused platelet transfusion refractoriness, that was first reported in China. To ensure the efficacy of platelet transfusion, the CD36-deficiency patient should receive CD36 deficiency platelets for transfusion.</p>

Molecular typing of human platelet antigens in immune thrombocytopenia patients in northern Brazil

ABSTRACT Background: Immune thrombocytopenia is an immune disease characterized by thrombocytopenia and bleeding due to platelet antibodies against platelet membrane glycoproteins. Human platelet antigens are derived from polymorphisms of these glycoproteins. The aim of this study was to investigate human platelet antigen frequencies in immune thrombocytopenia patients from the state of Amazonas, Brazil and investigate the potential association between specific antigens and risk for immune thrombocytopenia. Method: Human platelet antigen typing was performed by BeadChip technology to determine allelic variants of 11 systems (HPA-1 to HPA-9, HPA-11 and HPA-15). Thirty-six patients (8 male and 28 female) with a median age of 34 years (range: 9-69 years) were evaluated and compared with data from Amazonas blood donors. Results: Platelet counts varied from 3 to 98 × 109/L. The allele frequencies were 0.944 for HPA-1a, 0.056 for HPA-1b, 0.847 for HPA-2a, 0.153 for HPA-2b, 0.555 for HPA-3a, 0.444 for HPA-3b, 0.805 for HPA-5a, 0.222 for HPA-5b, 0.9975 for HPA-9a, 0.025 for HPA-9b, 0.486 for HPA-15a and 0.513 for HPA-15b. Among immune thrombocytopenia individuals, no b allele of the HPA-4, -6, -7, -8 and -11 were found. Conclusions: The results suggest HPA-1a, HPA-3b and HPA-5b are immune thrombocytopenia-specific autoepitopes.

Application of recombinant GPⅢa combined Luminex beads for the detection of HPA-1a antibody / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To generate recombinant GPⅢa as an alternative source for HPA-1a antigen and combine it with Luminex xMAP beads for the detection of HPA-1a-specific alloantibody.</p><p><b>METHODS</b>The full coding region of ITGB3 gene was amplified and ligated with pcDNA3.1. The recombinant plasmid was transfected into CHO cells, and those with stable expression were screened with G418. Expressed protein was identified and coupled with Luminex xMAP beads, which were then reacted with sera samples. Subsequently, phycoerythrin-labeled anti-species IgG antibody was added to the reaction wells and the median fluorescence was determined on a Luminex-100 analyzer.</p><p><b>RESULTS</b>DNA sequencing confirmed that the cloned ITGB3 gene was HPA-1aa. The recombinant GPⅢa was coupled with Luminex xMAP beads. The sensitivity of Luminex beads assay to detect HPA-1a antibody was dilution 1/32 (3.125 U/mL). The Luminex beads assay could specifically identify the HPA-1a antibody from the test sera, and the results were consistent with that of monoclonal antibody-specific immobilization of platelet antigens (MAIPA) technology. Cross-reactivity was not observed with the samples containing HLA, ABO and other HPA antibodies (HPA-3a and HPA-5b). The results illustrated that to detect HPA antibody with Luminex xMAP beads technology is feasible.</p><p><b>CONCLUSION</b>Recombinant GPⅢa was successfully obtained and used to establish a Luminex technology-based method for the detection of HPA antibodies.</p>

Analysis of HPA1-16 and HLA-A, B gene polymorphisms among ethnic Han population from Shandong / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the polymorphisms of human platelet antigen (HPA) 1-16 and human leukocyte antigen (HLA)-A and -B loci among ethnic Han population from Shandong.</p><p><b>METHODS</b>A total of 588 samples from platelet donors were genotyped for the above loci with sequence-specific primer PCR and sequence-specific oligonucleotide probe PCR.</p><p><b>RESULTS</b>The frequencies of HPA-la, -1b, HPA-2a, -2b, HPA-3a, -3b, HPA-4a, -4b, HPA-5a, -5b, HPA-6a, -6b, HPA-15a, -15b were 0.9974, 0.0026, 0.9456, 0.0544, 0.5417, 0.4583, 0.9983, 0.0017, 0.9889, 0.0111, 0.9903, 0.0097, 0.5434 and 0.4583, respectively. The HPA-7-14 and HPA-16 showed no heterozygosity as the b allele was not detected in such loci. The most common genotypic combination for HPA was HPA-(1,4,7-14,16,17) aa-2aa-3ab-5aa -6aa-15ab (0.1820). HLA-A2 (0.3070) and HLA-B13 (0.1361) demonstrated the highest frequencies at their respective loci.</p><p><b>CONCLUSION</b>The HPA and HLA loci are highly polymorphic among ethnic Hans from Shandong. The distribution of HPA polymorphisms also shows a great ethnic and territorial difference. It is important to construct regional database for the genotypes of HPA and HLA loci for platelet donors.</p>

Polymorphism of Platelet Specific Antigens (HPA-1-5, 15) in Han Donors in the North Area of Henan Province / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To study the gene polymorphism distribution characteristics of human platelet HPA-1-5 and 15 blood group antigens and construct a certain scale of platelet HPA database in the north area of Henan Province so as to provide platelet apheresis for clinical departments.</p><p><b>METHODS</b>Using polymerase chain reaction with sequence-specific primers (PCR-SSP), the genotyping of HPA-1-5 and 15 system was carried out; the periperal blood of 500 healthy Han donors in north area of Henan Province was collected randomly, the gene and genotype frequencies were detected by direct counting method, and the population distribution frequncy of HPA genes was analyzed by Hardy-Weinberg balance test, and compared with other regions and ethnics by using χ(2) test.</p><p><b>RESULTS</b>There was statistically significant (P < 0.05) of increase HPA-3b and HPA-5a in North area of Henan Province, compared with Chinese Han population; the HPA-3b and 5a increase and HPA-2a decrease were statistically significant (P < 0.05), compared with Ethnic minority of China. There was partly increase of HPA-1a, 2a, 3a and 5a, compared with different regions and ethnic in abroad. HPA allele genes of 500 Han donors in the North area of Henan Province were as follows: 0.985 and 0.015 for 1a and 1b; 0.924 and 0.076 for 2a and 2b; 0.469 and 0.531 for 3a and 3b; 1.000 and 1.000 for 4a and 5a; 0.532 and 0.468 for 15a and 15b, respectively. HPA allele gene frequencies were 1aa0.970, 1ab0.030; 2aa0.848, 2ab0.152; 3aa0.222, 3ab0.494, 3bb0.284; 4aa1.000; 5aa1.000; 15aa0.282, 15ab0.500, 15bb0.218. Compared with other regions and ethnic, HPA gene frequencies partly had statistical significance.</p><p><b>CONCLUSION</b>Distribution of HPA allele frequencies in the North area of Henan province is in accordence with the Hardy-Weinberg law. There are race and regional differences in HPA allele gene frequencies, compared with other regions and countries. And the HPA systems HPA-3 and 15 display the genetic polymorphisms, which provides a theoretical basis for the relevant research of the same type platelet infusion and alloimmune thrombocytopenia.</p>

The absence of the human platelet antigen polymorphism effect on fibrosis progression in human immunodeficiency virus-1/hepatitis C virus coinfected patients

Hepatic fibrosis progression in patients with chronic hepatitis C virus infections has been associated with viral and host factors, including genetic polymorphisms. Human platelet antigen polymorphisms are associated with the rapid development of fibrosis in HCV-monoinfected patients. This study aimed to determine whether such an association exists in human immunodeficiency virus-1/hepatitis C virus-coinfected patients.

Research Progress on Cytometric Bead Assay for Platelet Antibody Detection / 中国实验血液学杂志

Anti-platelet specific antibody is one of the most important reasons leading to thrombocytopenia and megakaryocyte dysmaturity. The detection of platelet autoantibodies is an important step in the diagnosis of ITP because of the absence of specific clinic feature. The monoclonal antibody-specific immobilization of platelet antigens (MAIPA) has become a "gold standard" for determination of PLT specific antibody, which has high specificity and low sensitivity. However, this assay is time-consuming and tedious work. Routine use of this assay in hospital is difficult. Recently, some researches reporded the cytometric bead assay that has higher sensitivity than MAIPA, and so probably solves the problem of time-consuming partly, that also can use different beads for simultaneous detection. This review focuses on recent progress of the cytometric bead assay.

Influence of Anticoagulants on Detection of ITP Platelet-Specific Autoantibodies and Relationship of Autoantibody Types with Glucocorticoid Efficacy / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the influence of divalent cation chelator EDTA and heparin sodium on the detection of ITP platelet-specific autoantibodies by the modified monoclonal antibody immobilization of platelet antigen assay (MAIPA) and to explore the relationship between types of platelet specific autoantibodies and glucocorticoid efficacy.</p><p><b>METHODS</b>The samples were obtained from EDTA- and heparin- anticoagulant ITP patients, respectively, so as to detect the platelet-specific autoantibodies (GPIIb/IIIa and GPIbα) in 140 ITP samples by modified MAIPA, then the differences between these two methods were compared.</p><p><b>RESULTS</b>Out of 140 cases in EDTA group, 55 cases were positive for GPIIb/IIIa, while 76 cases in heparin group were positive for GPIIb/IIIa, 42 cases in both group were repeatable; among them 13 cases were positive in EDTA group and negative in heparin group, while 34 cases were positive in heparin group and negative in EDTA group, there was significant difference between them (x (2) = 9.38, P < 0.05), 62 cases in 140 cases of EDTA group were positive for GPIba, while 51 cases in heparin group were positive for GPIba, 42 cases in both group were repeatabe; among them 20 cases were positive in EDTA group and negative in heparin group, while 9 cases were positive in heparin group and negative in EDTA group, there was no significant difference between them (x (2) = 3.44, P > 0.05). A total of 320 cases received a standard glucocorticoid treatment, out of them 143 cases were positive for GPIbα with effective rate 39.9%, 177 cases were negative for GPIbα with effective rate 79.7%, there was statisticalty significant difference between them (x (2) = 53.115, P < 0.05).</p><p><b>CONCLUSION</b>EDTA anticoagulant (a divalent cation chelator) has a significant influence on detection of ITP platelet-specific autoantibodies (GPIIb/IIIa) by a modified MAIPA method and the GPIbα antibody positive may be one of the important factors that results in un-sensitivity of ITP patients to glucocorticoid treatment.</p>