Human RBCs blood group conversion from A to O using a novel α-N-acetylgalactosaminidase of high specific activity

α-N-acetylgalactosaminidase (αNAGA) can convert group A human red blood cells (RBCs) to group O. One novel αNAGA gene was cloned by PCR from Elizabethkingia meningosepticum isolated from a domestic clinical sample. Pure recombinant αNAGA was obtained by genetic engineering and protein purification with a calculated molecule of 49.6 kD. αNAGA was selective for terminal α-N-acetylgalacto-samine residue with a high specific activity. αNAGA could completely remove A antigens of 1 U (about 100 mL) group A1 or A2 RBCs in 1 h at pH 6.8 and 25℃ with a consumption of 1.5 or 0.4 mg recombinant enzyme. Enzyme-converted group A RBCs did not agglutinate after being mixed with monoclonal anti-A or sera of groups A,B,AB and O. Other blood group antigens except ABO had no change. FCM analy-sis showed that A antigens and A1 antigens disappeared while H antigens increased. It indicated that αNAGA successfully converted human blood group A RBCs to universally transfusable group O RBCs without the risk of ABO-incompatible transfusion reactions. This αNAGA was suitable for producing universal RBCs to increase clinical transfusion safety,improve the RBCs supply,and to decrease transfusion cost and support transfusion service in case of emergency.

产生抗D的DVI type 3型孕妇免疫血清学和RHD基因型分析

目的:对部分D表型孕妇进行免疫血清学和RHD基因型分析。方法:采用常规血型血清学方法鉴定孕妇RhD血型,并进行血型特异性抗体筛查和鉴定;采用序列特异性引物聚合酶链反应(polymerase chain reactionsequence specific primer,PCR-SSP)鉴定孕妇RHD基因型;采用多重连接依赖的探针扩增技术(multiplex ligationdependent probe amplification,MLPA)对孕妇及其配偶和女儿的RhD血型抗原进行基因分型及遗传分析。结果:该孕妇血清中检测出IgG抗-D,其抗体效价为1∶8。PCR-SSP结果显示,该孕妇RHD基因第3-6外显子缺失,经鉴定该孕妇RHD基因型为DVI type 3型。MLPA分析显示,该孕妇只有1条RHD等位基因,且缺失3-6外显子,其基因型为CDVIe/cde,其配偶为CDe/CDe纯合子基因型,女儿为CDe/CDVIe基因型。结论:准确的RhD血型鉴定对制定安全有效的临床输血策略和对育龄妇女采取恰当措施及预防新生儿溶血病具有重要意义。

保存期间试剂红细胞血型相关膜蛋白抗原性研究

目的研究红细胞膜蛋白抗原稳定性随保存时间变化。方法 D抗原、Fy^a抗原、Jk^a抗原、在保存节点（0、14、28、42 d）,对上述红细胞血型抗原抗原性进行检测。结果在标化后的抗体范围,使用国际标准抗体,应用流式细胞术,在42 d检出对比组之间的D抗原抗原性差异具统计学意义（下降11. 3%; P〈0. 05）; 42 d时,应用微柱凝胶卡,使用国际标准品（下降33%）、单克隆IgG-D（下降66%）、IgM-D（下降26%）,检出对比组之间的D抗原抗原性差异具统计学意义（P〈0. 01）,Fy^a抗原抗原性检出对比组之间的差异具统计学意义（下降33%,P〈0. 05）,Jk^a抗原抗原性未检出,对比组之间的差异具统计学意义。结论实验室应定期对谱细胞进行质控,对于弱抗体的检测宜使用较新鲜的谱细胞或新鲜细胞进行检测及确认。

中国哈尔滨地区满族人群11个红细胞血型系统24种稀有血型抗原的基因多态性研究

目的:初步了解中国哈尔滨地区满族人群的11个红细胞血型系统24种抗原基因的多态性特征。方法:采用聚合酶链式反应-序列特异性引物法(PCR-SSP)技术,对200例哈尔滨地区满族人群进行GYPB(S/s)、Duffy、Kell、Dombrock、Diego、,Kidd、Scianna、Colton、Lutheran、Yt、Mur等11个血型系统的S、s;Fy^a、Fy^b;K、k;Do^a、Do^b;Di^a、Di^b;JK^a、JK^b;Sc1、Sc2;Co^a、Co^b;Lu^a、Lu^b;Yt^a、Yt^b;Kp^a、Kp^b;Mur1、Mur2等共计24个抗原基因进行检测和分型。结果:哈尔滨地区满族人群GYPB(S/s)血型系统基因频率为:S=0.0625,s=0.9325;Duffy血型系统基因频率为:Fya).0525,Fyb_=0.9475;Dombrock血型系统基因频率为:Do^a=0.1250,Do^b=0.8750;Diego血型系统基因频率为:Di^a=0.0275,Di^b=0.9725;Kidd血型系统基因频率为:JK^a=0.5650,JK^b=0.4350;Mur血型系统基因频率为:Mur1=0.0050,Mur2=0.9950;Kell、Scianna、Colton、Lutheran、Yt血型系统抗原基因频率不具有多态性,基因型分别为kkKp^bKp^b,Sc1Sc1,Co^aCo^a,Lu^bLu^b,Yt^aYt^a。结论:哈尔滨地区满族人群GYPB(S/s)、Duffy、Dombrock、Diego、Kidd和Mur血型系统抗原基因频率具有多态性,而Kell、Scianna、Colton、Lutheran、Yt血型系统呈抗原基因频率单态性分布。