Establishment Of HPA-typed Platelet Donor Registry And Analysis Of Effect Of Platelet Transfusion

ObjectiveTo study the genetic polymorphism of HPA-1-5 and HPA-15 in Han Chinese living in Changchun, understand the probability of HPA mismatching and antibody formation, identify human platelet antigen system that has clinical significance, and establish platelet gene frequency database and HPA-typed platelet donor registry, providing a basis for rapid identification of suitable donors.Identify the specificity of homologous platelet antibody and platelet antigen genotype in patients received many times of blood component transfusions, so as to find out matched platelet donors and avoid ineffective platelet transfusion caused by homologous immunity.MethodThe study in 126 healthy voluntary Han Chinese blood donors without blood relations. Calculate allele frequency, genotype frequency and compare the results with those in other populations.Use solid-phase agglutination assay and micro-column gel agglutination assay to detect homologous platelet antibody and identify the specificity of antibody in 300 cases of blood component transfusion. Understand the relationship between disease, blood component transfusion, and positive rate of platelet antibody, and the relationship between the amount of the transfused blood, times of transfusions and positive rate of platelet antibody.Develop standardized platelet compatibility testing technology, i.e. the detection of homologous platelet antibody, the genotyping of donor and recipient's platelet antigen, and cross-matching.Divide the 180 patients with positive homologous platelet antibody into three groups. One group receives transfusion of random platelet that donated by people with the same blood group. One group receives cross-matched platelet transfusion. And another receives antigen gene matched platelet transfusion. After transfusion, compare the CCI and PPR of the three groups. ResultsThe gene frequency of HPA-1~5 and HPA-15 is HPA-1a 0.9762,HPA-1b 0.0238, HPA-2a 0.9008, HPA-2b 0.0992, HPA-3a 0.6389, HPA-3b 0.3611, HPA-4a 1.0000,HPA-4b 0.0000,HPA-5a 0.9841, HPA-5b 0.0159, HPA-15a 0.4802, and HPA-15b 0.5198 respectively. HPA-4 is monomorphic, only HPA-4a allele is detected, and its frequency is 1.0000. HPA-4b allele is not detected. HPA-1, 2, 3, 5 and15 is polymorphic. Among HPA-1~5 and HPA-15, HPA-3 and HPA-15 has the highest heterozygosity (a/b heterozygous genotype), i.e. 0.5159 and 0.5317 respectively, and comparatively high mismatching rate of antigen, i.e. 0.3550 and 0.3746 respectively. HPA-1, 2, 4, 5 is mainly a/a homozygous genotype, 0.9524, 0.8016, 1.0000 and 0.9683 respectively and no b/b homozygous genotype is detected. HPA-3, 15 found b/b homozygous genotype is detected, i.e. 0.1032 and 0.2540.Researches shows that, HPA-1, 2, 3, 5, 15 in population living in the north of China is polymorphic, among which HPA-3 and HPA-15 has higher heterozygosity. Hardy-Weinberg test shows that this complies with Hardy-Weinberg equilibrium.There is significant difference in HPA-1 and HPA-2 between randomly selected Han Chinese blood donors in Changchun and Taiwanese; There is significant difference in HPA-5 compare with American blacks; There is significant difference in HPA-1 and HPA-5 compare with American whites; There is significant difference in HPA-1, HPA-4, and HPA-5 compare with Han Chinese in Beijing; There is difference in HPA-1 compare with Han Chinese in Shanghai, which has statistical significance (P<0.05).In 300 cases of patients received blood component transfusion, 180 cases have positive results in platelet antibody detection. The study of antibody specificity shows that, 20 cases have pure HPA antibody, i.e. HPA-2 antibody, HPA-3 antibody, HPA-5 antibody, and HPA-15 antibody.Aplastic anaemia is the most common disease caused by positive platelet antibody, followed by myelofibrosis, and myelodysplastic syndrome (χ~2=36.13,P<0.0001). Repeated platelet transfusion is the most common risk factor for homologous platelet antibody, and followed by whole blood transfusion, and red blood cells transfusion (χ~2=46.78,P<0.0001). The positive rate of platelet antibody rises with the increase in amount of transfused blood and times of transfusions. (transfusions:χ~2cmh= 50.26 P<0.0001,The number of blood transfusion:χ~2cmh= 67.05 P<0.0001).The comparison of the three transfusion methods shows that, platelet gene matching group and serology cross-matching group has higher CCI and PPR than the group that receives random platelet from the same blood group. There is no significant difference in CCI and PPR between the platelet gene matching group and serology cross-matching group (H=124.38,123.20,135.14,140.64,P<0.0001).Conclusion1.HPA- 1~5 and HPA-15 in 126 healthy voluntary Han Chinese blood donors (some are family members of the patients) without blood relations in Changchun is genotyped.2.Research shows that HPA-1,2,3,5 and15 is polymorphic. HPA-3 and HPA-15 has highest heterozygosity and comparatively high mismatching rate of antigen, indicating clinical and immunological significance.3.Platelet gene frequency database and HPA-typed platelet donor registry is established.4.Immunological factor and effect of different transfusion methods in cases of patients positive platelet antibody is analyzed5.Standardized platelet compatibility testing technology is developed, i.e. the detection of homologous platelet antibody, the genotyping of donor and recipient's platelet antigen, and cross-matching.