[Identification of RhCcEe Mixed Visual Field in Patients with Regular Blood Transfusion and Efficacy Analysis of the Matched Transfusion].

OBJECTIVE: To explore the feasibility of RhCcEe blood group antigen mixed visual field identification in patients with regular blood transfusion, to follow up and evaluate the efficacy of matched transfusion and its clinical significance. METHODS: RhCcEe genotyping for 142 patients with regular transfusion in our hospital was carried out by PCR-SSP method. According to the results of genotyping, 48 patients voluntarily selected the continuous transfusion of RhCcEe matched red blood cells, 46 patients received random blood transfusion (RhCcEe mismatched transfusion), 42 patients received partial RhCcEe matched transfusion (unable to provide fully matched RhCcEe donors each time), and 6 patients' blood transfusion data were lost. After 3-6 months of the RhCcEe matched transfusion, all patients were tested by RhCcEe microcolumn gel card and compared with the results before RhCcEe matched transfusion. The positive rates of alloantibodies, DAT and the percentage of red blood cell invalid transfusion were followed up and evaluated for the above-mentsioned 3 types of regular transfusion patients in the past 5 years. RESULTS: Out of the 48 patients who underwent conti-nuous RhCcEe matched transfusion, only 1 case showed stratification, the remaining 47 cases had clear gel card results without stratification, suggesting that PCR-SSP genotyping was feasible. In addition, another 42 patients who could not receive RhCcEe matched transfusion each time and 46 patients with random blood transfusion were found to have a mixed vision phenomenon again. but the results was still difficult to confirm the results. For the transfusion results in the past 5 years, follow-up analysis showed that there were 1 case alloantibody (anti-Jka) (1/48) , 1 case of DAT positive (1/48) and 2 cases of invalid transfusion (2/48) in the RhCcEe matched transfusion group; 7 cases of alloantibodies (3 anti-E, 1 anti-E+anti-c, 1 anti-C, 1 anti-M, 1 anti-Fya) (7/46), 6 case of DAT positive (6/46) and 9 case of invalid transfusion (9/46) in the random transfusion group; 6 cases of alloantibodies (1 anti-E, 1 anti-E+autoantibody, 1 anti-C, 1 anti-c, 1 anti-M and 1 other antibody) (6/42) and 7 case of DAT positive (7/42) and 8 case of invalid transfusion (8/42) in the partial RhCcEe matched transfusion group. The statistical analysis showed that the positive rate of alloantibodies and the invalid infusion rate of RBC in each group were significant differences between RhCcEe matched transfusion group and the random transfusion group as well as betwen Rhce fe matched transfusion group and the partial matched transfusion group（P＜0.05）, but there was no statistical difference between the random transfusion group and the partial matched transfusion group（P>0.05）. CONCLUSION: PCR-SSP genotyping technique can be used to detect RhCcEe mixed vision in patients with regular blood transfusion. Continuous RhCcEe matched transfusion can effectively prevent the occurrence of alloimmunization, and improve the clinical transfusion efficacy and safety of the patients with regular blood transfusion, which has very important clinical significance.

Rh-Matched Transfusion through Molecular Typing for ß-Thalassemia Patients Is Required and Feasible in Chinese.

BACKGROUND: Molecular typing for RHCE blood group alleles has been established in many countries for patients and blood donors. In the Chinese literature nearly 80% of transfused patients with alloimmunization have antibodies specific for antigens of the Rh blood group system. We investigated if it is feasible to match packed red blood cells (RBCs) for Chinese ß-thalassemia patients by RHCE genotyping. METHODS: In this study, 481 patients with ß-thalassemia were enrolled. They were genotyped for RHCE alleles by a simple PCR method with sequence-specific primers (PCR-SSP). Among these patients, 203 continuously received RBCs of the identical Rh subgroups according to the genotyping results for at least 3 months. Subsequently, their phenotypes were tested through a micro-column gel card method. For validation purposes, 400 donors were serologically typed with the same technology, of which 164 were genotyped too. Finally, the C, c, E, and e frequencies and the feasibility of the simple genotyping method were analyzed. RESULTS: All patients showed mixed-field agglutination in the Rh subgroup gel cards before the same Rh subgroups in blood donors were selected for blood transfusion. The results, however, lacked mixed-field agglutination in all 203 cases after transfusion with RBC concentrates selected for the patient's C, c, E, and e antigens for at least 3 months. The genotyping results of 164 donors were all consistent with the serological results. Whole coding regions of RHCE were sequenced in 7 individuals with weak c, E, or e antigens. In only one sample we observed a 1059G>A nucleotide mutation coding for a truncated RhCE polypeptide (GenBank KT957625), in the other 6 samples no sequence variant was found. Both patients and donors were predominantly CcEe and CCee, with a prevalence of 55.3% and 24.9% for patients or 49.3% and 31.3% for donors, respectively. It revealed that about 80% of Chinese could receive Rh-matched RBCs easily. CONCLUSION: A simple RHCE genotyping technique is safe enough for Rh-matched transfusion of ß-thalassemia patients in Chinese Han.

Development of a Strategy Based on the Surface Plasmon Resonance Technology for Platelet Compatibility Testing.

BACKGROUND: This study was aimed to establish a novel strategy based on the surface plasmon resonance (SPR) technology for platelet compatibility testing. METHODS: A novel surface matrix was prepared based on poly (OEGMA-co-HEMA) via surface-initiated polymerization as a biosensor surface platform. Type O universal platelets and donor platelets were immobilized on these novel matrices via amine-coupling reaction and worked as a capturing ligand for binding the platelet antibody. Antibodies binding to platelets were monitored in real time by injecting the samples into a microfluidic channel. Clinical serum samples (n = 186) with multiple platelet transfusions were assayed for platelet antibodies using the SPR technology and monoclonal antibody-immobilized platelet antigen (MAIPA) assay. RESULTS: The novel biosensor surface achieved nonfouling background and high immobilization capacity and showed good repeatability and stability after regeneration. The limit of detection of the SPR biosensor for platelet antibody was estimated to be 50 ng/mL. The sensitivity and specificity were 92% and 98.7%. It could detect the platelet antibody directly in serum samples, and the results were similar to MAIPA assay. CONCLUSIONS: A novel strategy to facilitate the sensitive and reliable detection of platelet compatibility for developing an SPR-based biosensor was established in this study. The SPR-based biosensor combined with novel surface chemistry is a promising method for platelet compatibility testing.

[Family investigation of a RHD 845A/1227A genotype individual].

This study was aimed to investigate 1 case of rare RHD845A/1227A genotype pedigree and analyse their characters. The D antigen was determined by saline method and indirect anti-globulin test (IAT), the RHD1227A, RHD845A alleles and RHD zygosity were detected by PCR-SSP assay, the RHD coding region was analysed by gene sequencing. The results showed that the serological result of RH(D) antigen was found to be negative in one sample by saline assay, but positive by IAT. The analysis of RHD gene sequence indicated that RHD genes in the 845th and 1227th location were G/A base heterozygosis, it was speculated that the individual genotype may be RHD845A/1227A. Family investigation demonstrated the proband's father was RhD negative, his mother was RhD positive, the results of PCR-SSP assay showed that his father carried the RHD1227A alleles, whose genotype was RHD1227A/RHD(-), however, his mother carried RHD845A alleles, her genotype was RHD845A/RHD(+), which proved that the proband's genotype was RHD845A/1227A, inheriting the RHD1227A and RHD845A alleles from his father and mother respectively. It is concluded that 1 case of rare RHD845A/1227A genotype is found, further study proved that this rare heterozygosis come from the hereditary of RHD845A and RHD1227A alleles, rather than the formation of individual gene mutation.