[Feasibility Analysis of Establishing Combat Readiness Blood Bank Based on Low Titer Group O Whole Blood and Group A Plasma].

OBJECTIVE: To explore the feasibility of establishing combat readiness blood bank with low titer group O whole blood and group A plasma. METHODS: The Galileo automatic blood analyzer was used to detect the titers of IgM anti-A and anti-B antibodies in the samples of group O blood donors and IgM anti-B titer in the samples of group A blood donors. Group O blood donors with antibody titers below 128 were selected and included in the mobile blood bank for combat readiness, group A plasma with anti-B titer lower than 128 and group O whole blood with antibody titers below 128 were included in the combat readiness entity blood bank. RESULTS: A total of 1 452 group O blood donors were selected, and the anti-A/B antibody titers were detected. Both antibody titers were distributed below 512, and both peak values of sample distribution were at titer 4. The proportion of samples with titers>128 for both antibodies was relatively low. There was a significant positive correlation between the titers of the two antibodies (r =0.383), and the proportion of samples with IgM anti-A titer higher than IgM anti-B titer was relatively high. 1 335(91.94%) group O blood donors with IgM anti-A and anti-B antibody titers <128 could be included in the mobile blood bank. The anti-B titer of group A blood was detected in 512 cases and the results showed that as the antibody titer increased, the proportion of blood donors gradually decreased. 99.8% of group A blood donors had anti-B antibody titer less than 128, and only one case did not meet the inclusion criteria. CONCLUSION: The proportion of group O blood donors whose whole blood meet the low antibody titer standard is high, and almost all plasma of group A blood donors meet the low titer standard, which improves the blood supply rate in emergencies.

[Platelet Transfusion Strategies for MASPAT-Matched Platelet Transfusion Failed Patient with Allogeneic Hematopoietic Stem Cell Transplantation].

OBJECTIVE: To investigate the causes of ineffectiveness of platelet transfusion with monoclonal antibody solid phase platelet antibody test (MASPAT) matching in patients with allogeneic hematopoietic stem cell transplantation and explore the strategies of platelet transfusion. METHODS: A case of donor-specific HLA antibodies (DSA) induced by transfusion which ultimately resulted in transplantation failure and ineffective platelet transfusion with MASPAT matching was selected, and the causes of ineffective platelet transfusion and platelet transfusion strategy were retrospectively analyzed. RESULTS: The 32-year-old female patient was diagnosed as acute myeloid leukemia (high risk) in another hospital with the main symptoms of fever and leukopenia, who should be admitted for hematopoietic stem cell transplantation after remission by chemotherapy. In the course of chemotherapy, DSA was generated due to platelet transfusion, and had HLA gene loci incompatible with the donor of the first transplant, leading to the failure of the first transplant. The patient received platelet transfusion for several times before and after transplantation, and the results showed that the effective rate of MASPAT matched platelet transfusion was only 35.3%. Further analysis showed that the reason for the ineffective platelet transfusion was due to the missed detection of antibodies by MASPAT method. During the second hematopoietic stem cell transplantation, the DSA-negative donor was selected, and the matching platelets but ineffective transfusion during the primary transplantation were avoided. Finally, the patient was successfully transplanted and discharged from hospital. CONCLUSIONS: DSA can cause graft failure or render the graft ineffective. For the platelet transfusion of patients with DSA, the platelet transfusion strategy with matching type only using MASPAT method will miss the detection of antibodies, resulting in invalid platelet transfusion.

[Correlation Analysis of Hemolytic Transfusion Reaction Induced by Low Titer Antibody].

OBJECTIVE: To establish the diagnostic process of low titer blood group antibody in the occurrence of adverse reactions of hemolytic transfusion. METHODS: Acid elusion test, enzyme method and PEG method were used for antibody identification. Combined with the patient's clinical symptoms and relevant inspection indexes, the irregular antibodies leading to hemolysis were detected. RESULTS: The patient's irregular antibody screening was positive, and it was determined that there was anti-Lea antibody in the serum. After the transfusion reaction, the low titer anti-E antibody was detected by enhanced test. The patient's Rh typing was Ccee, while the transfused red blood cells were ccEE. The new and old samples of the patient were matched with the transfused red blood cells by PEG method, and the major were incompatible. The evidence of hemolytic transfusion reaction was found. CONCLUSION: Antibodies with low titer in serum are not easy to be detected, which often lead to severe hemolytic transfusion reaction.

[Effect of 25 Gy (60)Co Irradiation on the Physico-chemical Property and Functions of the Platelets During Storage].

OBJECTIVE: To evaluate the effects of the 25 Gy 6°Co irradiation on the physiological and biochemical properties and the functions of the platelets during storage. METHODS: A total of 15 bags of platelets were apheresis-collected from 15 healthy donors, and each bag of platelets were divided into 2 parts, then the platelets were divided into the control group (without 25 Gy 6°Co irradiation) and the irradiated group (with 25 Gy 6°Co irradiation) groups. The two groups of platelets were kept under the condition of (22 ± 2) °C and shaken. The Platelet count and pH value were detected on the d 1, d 2, d 3, d 4 and d 5. The variables such as R, K values, α angle and maximal amplitude (MA) were measured by thrombelastography on the same days. Hypotonic shock response (HSR), morphological score were devised. RESULTS: There were no statistically significant difference in Plt counts, mean platelet volume (MPV), platelet distribute width (PDW) and pH between the two groups (P > 0.05), and Plt count decreased on the end of storage. There were no marked changes in HSR level and morphological score between the two groups during storage, and there were no significant difference between the two groups (P > 0.05). In the TEG analysis there were no significant difference of the R, K, α angle and MA values between the two groups (P > 0.05). R value showed upward trend increased along with prolongation of preserved time (P < 0.01), no significant changes in α angle (P > 0.05), K value was slightly higher and MA value was lower in the last day of storage than the days 1-4 (P < 0.01), respectively. CONCLUSION: 25 Gy 6°Co gamma-ray irradiation can not damage the physiological, biochemical properties and the functions of the platelets during storage. In order to ensure the best curative effect, it is suggested that no matter the platelets were irradiated or not, the platelets should be used as soon as possible.

[Establishment of genotyping method for fetal ABO group from pregnant maternal peripheral blood].

This study was aimed to establish a genotyping method to detect ABO group gene of fetus from peripheral blood of pregnant women for prenatal diagnosis of hemolytic disease of newborn (HDN) resulting from ABO blood group incompatibility. 4 pairs of primers were designed according to ABO blood group gene DNA and mRNA sequences. 20 plasma DNA samples from healthy donors were extracted and amplified to explore the best conditions for plasma DNA extraction and PCR amplification. The O group plasma DNA was mixed with A group or B group plasmas by the ratios of 1:1, 2:1, 4:1, 8:1, 10:1, 20:1, 40:1, 100:1 to simulate the status of mixed ABO gene from pregnant maternal blood and to establish the mixed blood group ABO genotyping technology. The pregnant maternal blood samples with more than 30 weeks of gestation were selected for detecting the fetal ABO blood group genotype. The blood samples should be taken as possible as after birth for identification of ABO blood group and evaluation of sensitivity and accuracy of fetal ABO blood group genotyping technology through peripheral blood of pregnant women. The results indicated that the minimal amount of template DNA from single blood plasma for accuracy identification was at least about 0.625 ng, the DNA amount extracted from 500 microl of plasma could meet the requirement for PCR amplification. When the proportion of O group plasma DNA in mixed plasma DNA was