Platelet Activation of Stored Platelets with Storage / 대한수혈학회지

BACKGROUND: Effects of storage period on platelet activation of random-donor platelets (RDP) prepared from whole blood units and single-donor platelets (SDP) prepared from single-donor apheresis collections have been investigated in this study. We also analyzed the correlation between amount of blood cells and platelet activation in random-donor platelets. METHODS: RDP and SDP were collected at 1 day, 3 day, or 5 day during storage. In case of SDP, whole blood was also collected just before apheresis. The platelet activation in RDP and SDP was measured by flowcytometry using monoclonal antibodies against CD41a, CD61 and CD62p. RESULTS: In SDP, MCFI against CD62p has been significantly increased during storage and any significant differences are not found according to the kinds of pheresis machines. In RDP, no significant differences in MCFI against CD62p were found with storage period and showed a increased MCFI dependent only on the number of platelets. CONCLUSION: Single-donor platelets should be used as soon as possible for transfusion due to progressive platelet activation with storage period. On the other hand, a proper number of platelets should be maintained under strict quality control system to minimize platelet activation in RDP.

Detection of platelet specific antigens by flow cytometry and genotyping method / 대한수혈학회지

BACKGROUND: To identify the human platelet antigens (HPA) associated with neonatal alloimmune thrombocytopenia (NATP), posttransfusion purpura (PTP), and platelet refractoriness, polymerase chain reaction-sequence specific primer (PCR-SSP) method and immunofluorescent method by flow cytometry were used. The frequencies of the genonotypes of HPA systems by PCR-SSP method and those of phenotypes by flow cytometry were determined. Then both types were compared each other and each types were compared with those of established reports. METHOD: Platelet suspensions were prepared from peripheral blood specimens of 200 blood donors and DNA specimens were extracted from those of 160 donors among them. Phenotypes of 200 specimens and genotypes of 160 ones were tested by flow cytometry and PCR-SSP method, respectively. RESLUTS: Frequencies of penotypes of HPA-1a, -3a, -4a, -4b and NaKa were 100.0%, 88.0, 100.0%, 0.5% and 94.0%, respectively. HPA-5 system could not be identified due to a few antigenic sites of HPA-5 systems. The genotype fequencies are of HPA-2 were a+b- 63.75%, a+b+ 35.00%, a-b+ 1.25%; HPA-3, a+b- 38.12%, a+b+ 48.13%, a-b+ 13.75%; HPA-4, a+b- 100.00%, a+b+ 0.00%, a-b+ 0.00%; HPA-5, a+b- 98.12%, a+b+ 1.88%, a-b+ 0.00%. The frequencies of HPA-4 and -5 were almost same as those of other reports but the frequencies of HPA-2 and -3 were somewhat different from others. Concordant rate between phenotype and genotype of HPA-3a,-4a and -4b were 95.6%, 100% and 99.4%, respectively. CONCLUSION: Phenotyping method by flow cytometry was rapid and objective for identifying HPA systems except HPA-5 system which has a few antigenic sites on platelet membrane. Especially it will be useful method for screening HPA-4b as possible cause of NATP in Koreans. But like other serologic methods, phenotyping by flow cytometry also require the highly qualified antiserum and appropriate amount of platelet. PCR-SSP method was also rapid and simple to test of genotypes of HPA-2~5 systems. Because PCR-SSP method is thought to be one of the most simple and economic genotyping methods to overcome the shortages of serologic methods, it is suggested to be the efficient screening method of HPA systems substituting the serologic methods in the cases which HPA sytems can not be identified by flow cytometry.

Comparison Between HLA-DR Serological Typing and O1igotyping / 대한임상병리학회지

BACKGROUND: In renal transplantation, a good HLA-DR match Is associated with successive graft outcome. But due to a number of technical problems, reliable serological DR typing cannot always be obtained. To compare the serological DR typing with DRBI DNA typing, we tested 103 specimens that had been frozen after serological typing, by PCR-SSOP typing method. METHODS: Serological DR typing was performed by complement-dependent microlymphocytotoxicity technique using commercial antisera kits, and DNA gyp ins was performed by PCR-SSOP, using one of the methods recommended by 12th International Histocompatibility Workshop. DNA amplification was done by DRBAMP-A and DRBAMP-B primers, and hybridization by 18 oligonucleotides labelled with digoxigenin.. RESULTS: The concordance rate between serologic typing and DNA typing was 76.7%. Most (79.0%) of discordant results were due to serological blanks turning out to be definable antigens by DNA typing and these antigens consisted of mainly DR5 splits but none of DR1, DR2, or DR7. CONCLUSIONS: In spite of technical improvement, serological typing method often can not define the accurate HLA-DR type. It is thought that combining serological typing with DNA typing Is necessary to achieve a higher success rate of graft outcome.