Identification of a novel DI02(2558T) allele associated with weakened expression of DI2 antigen
Identification of a novel DI02(2558T) allele associated with weakened expression of DI2 antigen
复制标题
鉴定与 DI2 抗原表达减弱相关的新型 DI02(2558T) 等位基因
作者：
Jizhi Wen;Emile Akker;Guangping Luo;Shuangshuang Jia;Ling Wei;Zhen Wang;C. Ellen Schoot;Yanli Ji
Diego血型系统的DI 1/DI 2抗原在蒙古族人群中的分布具有多态性，相应的同种抗体具有临床意义。本研究通过对1150例中国人的DNA样本进行DNA分型，采用桑格测序法进行DI*01/DI* 02基因分型。对新等位基因携带者，分别采用Western blot和流式细胞术检测红细胞表面带3和DI 1/DI 2抗原的表达。体外表达研究是通过将突变体（包括新颖的和三种型号的DI *02（2534 T）、DI*02（2358_2359insCAC）和DI *02（2572 T）等位基因）或野生型DI * 02构建到HEK 293 T细胞中，分析带3和DI 1/DI 2抗原的表达。在DI：-1，2表型的供体中鉴定了位于DI 1/DI 2多态性位点（c.2561T>C）附近的p.Thr853Met（c.2558C>T，p.Thr853Met）。在RBC上观察到DI 2抗原表达减少，而在用muplatin DI *02（2558 T）构建体转染的细胞中检测到条带3表达减弱和DI 2抗原缺失。结论DI *02（2558 T）等位基因和3个已报道的DI突变可影响Band 3蛋白和/或DI 2抗原的表达和/或干扰DI *01/DI* 02基因分型结果。
BackgroundThe distribution of DI1/DI2 antigens of the Diego blood group system is polymorphic in Mongoloid populations and the corresponding alloantibodies are clinically significant. Here a novelDIvariant was found by donor screening, and the effect of the novel and previously reported mutations on expression of DI1/DI2 antigens and Band 3 protein was explored.Study Design and MethodsDNA samples of 1150 Chinese donors were collected.DI*01/DI*02genotyping was determined by Sanger sequencing. For the carrier of novel allele, the expression of Band 3 and DI1/DI2 antigens on red blood cells (RBCs) was detected by Western blot and flow cytometry, respectively. in vitro expression studies were conducted by transfecting the mutant (including the novel and three reportedDI*02(2534T),DI*02(2358_2359insCAC),andDI*02(2572T)alleles) or wild‐typeDI*02constructs into HEK 293T cells, the expression of Band 3 and DI1/DI2 antigens was analyzed.ResultsA novel heterozygous mutation (c.2558C>T, p.Thr853Met), which is located near the DI1/DI2 polymorphism site (c.2561T>C), was identified in a donor with DI:‐1,2 phenotype. Reduced expression of DI2 antigen was observed on the RBCs, while weakened expression of Band 3 and absence of DI2 antigen were detected in cells transfected with the mutantDI*02(2558T)construct. In addition, absent or decreased expression of Band 3 and DI2 antigen was also detected in cells transfected with three reported mutant constructs.ConclusionThe novelDI*02(2558T)allele and three previously describedDImutations can affect the expression of Band 3 protein and/or DI2 antigen and/or interfere withDI*01/DI*02genotyping result.