ABSTRACT
【Objective】 To investigate the frequency of P1PK and GLOB blood group in Chinese Lahu population and their genetic status, so as to provide data support for the safety of blood transfusion and give advice and transfusion guidance for pregnant women. 【Methods】 Unrelated individuals of Chinese Lahu population were randomly selected for serological identification of P1PK and P blood group and gene sequencing analysis. The frequency of P1PK and GLOB blood group were analyzed. 【Results】 Six cases of anti-PP 1Pk(formerly known as anti-Tja) negative blood type were identified as the rare P1-PK-P- blood type (formerly known as Tja- blood type or p blood type, hereinafter referred to as p blood group) from 300 Lahu population, with phenotypic frequency of p blood group in P1PK and GLOB blood group system in Lahu population at 2.0%(6/300). 【Conclusion】 The phenotypic frequency of blood group p in Lahu population was significantly higher than that in Europe (5.8 persons per million) and Hong Kong, China (1 person per million),indicating significant ethnic specificity and regional ethnic differences.
ABSTRACT
【Objective】 To construct an in-vitro model of erythrocyte antibody-mediated complement activation, and establish quantitative detection methods based on flow cytometry and spectrophotometry, so as to explore the correlation of anti-body titers and complement activation speed, and provide a methodological basis for studying the adverse transfusion reactions of anti-body mediated complement hemolysis. 【Methods】 Mouse monoclonal antibody that recognized human C3b and fluorescent secondary antibody were used to label C3b fragments on erythrocytes, and the deposition of C3b fragments after complement activation was detected by flow cytometry. The absorbance at 540 nm of the supernatant in the complement activation reaction system was measured by spectrophotometry as the amount of hemoglobin released was related to the absorbance. 【Results】 The complement activation system was constructed according to the ratio of 3% red blood cell suspension (mixed for 6 people) 1∶anti-Tja 1∶complement 2. The repeatability was good (P value>0.05) as different red blood cell mixtures had been used to repeat the detection reaction system. When using 32×, 64× and 128× dilutions of anti-Tja mediated complement activation, the deposition of C3b fragments has been detected by flow cytometry at 30 s, 1 min and 2 min, respectively, and MFI peaked at 5 min, 10 min and 30 min, respectively. No obvious hemolysis has been observed within 1.5 h. 【Conclusion】 In vitro model of anti-Tja-mediated complement activation demonstrates the speed of complement activation is related to the concentration of antibody. At a certain antibody concentration, the speed of complement activation has been slowed down, and no obvious hemolysis observed.
ABSTRACT
【Objective】 To determine the rare ABO blood subgroups rapidly and ensure the blood transfusion safety of five patients by a series of serological tests and family investigation, as their preliminary serological results of ABO blood grouping was inconsistent. 【Methods】 ABO blood grouping, antibody screening and Coombs′ tests were performed by the routine serological methods, including manual tube and automatic blood group analyzer, which had matched micro-column gel cards from Diagnostic Grifols. Polymerase chain reaction (PCR) was used to amplify the 6 and 7 exons as well as their adjacent intron region of ABO gene. The patients and their relatives′ ABO blood group and subgroup were analyzed and identified through the comparison with serological phenotype database of ABO blood group. The products of PCR were sequenced directly, and the gene mutation was identified through the comparison with the Blood Group Antigen Gene Mutation Database. 【Results】 Whether micro-column gel cards or manual tube test, the forward and reverse tests of serological grouping were not supported by each other on the five patients′ ABO blood grouping. The forward tests of patients No.1~3 showed AwB phenotype and the reverse tests showed B group. No.4 patient was the forward ABw phenotype and the reverse A group, and No.5 patient was the forward normal AB phenotype and the reverse B group, respectively. All of 5 patients′ Rh C/D/E blood grouping showed clearly; the IDT test and antibody screening result of patient No.1 was positive, while the antibody screening result of patient No.4 was negative. 【Conclusion】 The blood group serological characterization of patient No.1~3 met B(A) blood group, and patient No.4~5 met CisAB blood group. These tests can make a preliminary diagnosis of blood group phenotype, which are verified correctly via blood group genotype.