International standards for minimum potency of anti-A and anti-B blood grouping reagents: evaluation of candidate preparations in an international collaborative study

BACKGROUND AND OBJECTIVES: The aim of the study was to evaluate lyophilized monoclonal IgM anti-A and anti-B preparations for use as international standards (IS) to specify recommended minimum potencies of anti-A and anti-B blood grouping reagents in tube tests. MATERIALS AND METHODS: The candidate IS for minimum potency of anti-A and anti-B blood grouping reagents, codes 03/188 and 03/164, respectively, were evaluated against a wide range of commercial anti-A and anti-B blood grouping reagents in an international collaborative study involving 16 laboratories in nine countries. Laboratories titrated 03/188 and 03/164 in parallel with as many commercial anti-A and anti-B blood grouping reagents, respectively, as were available to them, in tube tests according to specified haemagglutination methodology. Three of these laboratories and a further laboratory also titrated 03/188 and 03/164 in parallel with currently available reference preparations for anti-A and anti-B. The ratios of the mean endpoint titres of the anti-A and anti-B reagents to those of 03/188 and 03/164, respectively, within each laboratory were calculated. RESULTS: The ratios of the mean titres of the anti-A reagents to the mean titre of 03/188 within a laboratory fell within 0.062 and 4, i.e. the potencies of the anti-A reagents were between a sixteenth to four times as strong as 03/188. The ratios of the mean titres of the anti-B reagents to the mean titre of 03/164 within a laboratory also fell within 0.062 and 4, with one outlier. CONCLUSIONS: By international consensus, a 1 in 8 dilution of the candidate IS for anti-A, 03/188, and a 1 in 4 dilution of the candidate IS for anti-B, 03/164, were considered appropriate to define the recommended minimum potencies of anti-A and anti-B blood grouping reagents, respectively, in tube tests. On the basis of these results, preparations 03/188 and 03/164 were established by the World Health Organization as International Standards for Minimum Potency of Anti-A and Anti-B Blood Grouping Reagents respectively, and by the US Food and Drug Administration Center for Biologics Evaluation and Research as Minimum Potency Reference Reagents.     

3种HBV DNA荧光定量PCR试剂检测结果比较

目的 比较及评价3种HBV-DNA荧光定量PCR试剂检测结果的差异.方法 同时用3种HBV-DNA荧光定量PCR试剂对已知结果的质控血清、标准品及本院79份HBsAg阳性的临床标本进行检测,并对检测结果进行比较分析.结果 试剂A、B、C检测阳性率分别为41.77%(33例)、45.57%(36例)和41.77%(33例).3种方法结果一致者66例,总符合率83.54%.试剂A、B与试剂C检测结果相比差异有统计学意义(P<0.05),试剂A与B检测结果相比差异无统计学意义(P>0.05).试剂A与C的灵敏度、特异性均为77.78%、88.37%;试剂B灵敏度为89.66%、特异性80.00%.结论 试剂A与B总体性能优于试剂C,适于临床检测与筛查.实验室必须选择质量好且符合自己实验室要求、与本实验室仪器相匹配的试剂以保证检验质量.