Objective: To analyze the serological phenotypes and molecular genetic characteristics of a proband with ABO forward and reverse typing discrepancy and their family members, and to investigate the molecular genetic mechanism underlying the Ael/AelB phenotype caused by the c. 575T>C variant on an ABO A1.02 background. Methods: Serological testing and adsorption-elution assays were performed for blood group identification of the proband and family members. PCR-SBT, cloning sequencing, and Nanopore third-generation sequencing were used to analyze ABO gene variants and haplotypes. Phyre2 and PyMOL were used to predict the effect of the p. Ile192Thr variant on the structure of glycosyltransferase A (GTA), and plasma GTA activity was evaluated using an in vitro transferase assay. Results: Among thirteen family members, four members showed a serological phenotype consistent with the Ael subtype and one with the AelB subtype. Cloning sequencing and third-generation sequencing confirmed that five family members carried the ABO A1.02 (c. 575T>C) variant, which co-segregated with the weak A phenotype in the family. Structural modeling suggested that p. Ile192Thr may alter the local spatial conformation and hydrogen-bond interactions of GTA. Plasma GTA activity testing showed markedly reduced GTA activity in the tested individuals. Conclusion: The ABO A1.02 (c. 575T>C) variant is associated with the Ael/AelB phenotype. The p. Ile192Thr substitution may weaken A antigen expression by altering GTA conformation and reducing enzymatic activity. This study provides additional evidence for the role of this variant in the Ael/AelB phenotype from the perspectives of familial inheritance, full-length haplotype analysis, and functional assessment, which is important for accurate ABO subtype identification and individualized transfusion strategies.

Objective: To screen the frequency of CD36 antigen expression in platelet donor database in Shaanxi province and analyze the molecular genetic characteristics of samples with CD36 antigen deficiency and low expression. Methods: A total of 525 platelet donors samples were randomly collected during May 2023. CD36-FITC monoclonal antibody was used for immunofluorescence labeling, and flow cytometry was applied to detect the expression of CD36 antigen on platelets. For samples with CD36 antigen deficiency on platelets, the expression of CD36 on monocytes was further detected. Samples with CD36 antigen deficiency and low expression were sequenced and analyzed. Results: Among the 525 blood samples, 99.24% (521/525) showed positive expression of CD36 antigen. There were differences in the expression intensity of CD36 antigen, with low expression accounting for 3.43% (18/525) and CD36 antigen deficiency accounting for 0.76% (4/525), all of which were type Ⅱ deficiency. The exon mutation frequency of CD36 type Ⅱ deficiency and low expression samples was 31.82% (7/22), and the exon mutation types were 121-1_126delGCAAGTT, 329-330delAC, 1142T>G, 1204-1246dupl 43bp, 1221G>A, and 1228-1239delATTGTGCCTATT. All four cases of CD36 type Ⅱ deficiency had a 121-6 T>C mutation in intron 3. All CD36 low expression samples had a mutation of 282-10A>G, and 121-6T>C mutation rate was 61.1%(11/18). Conclusion: There were differences in the expression of CD36 antigen in the platelet donor database in Shaanxi province, which may be caused by multiple molecular genetic variations. The frequency of CD36 antigen deficiency in Shaanxi was lower than that of Han, Zhuang and Yao populations in southern China. This study provides references for solving the CD36 antibody mediated transfusion reaction and auxiliary treatment of diseases caused by CD36 antigen deficiency in the future. It also provides a basis for investigating the molecular mechanisms of CD36 deficiency and low expression.

Objective:To analyze a Chinese pedigree with a recombination occurring between the HLA- A/ C loci in both parents. Methods:A patient who was planning to undergo hematopoietic stem cell transplantation due to "aplastic anemia" in February 2022 was selected as the study subject. Peripheral blood samples were collected from the patient, his parents and brother. HLA- A/ C/ B/ DRB1/ DQB1 high-resolution typing was carried out by using sequence-based typing and sequence-specific oligonucleotides. The recombination was identified by pedigree analysis. The HLA haplotype of each individual was identified by genealogical analysis. The parentage possibility was determined by short tandem repeat analysis. HLA- A/ C/ B/ DRB1/ DRB345/ DQA1/ DQB1/ DPA1/ DPB1 were determined with next-generation high-throughput sequence-based typing. The recombination sites were analyzed by family study. Results:The high parentage possibilities of the family was confirmed by short tandem repeat analysis. Recombination was found between the HLA- A* 24: 02 A* 33: 03/ C* 14: 03 in the paternally transmitted haplotype, whilst HLA- A* 01: 01 A* 03: 01/ C* 08: 02 was found in the maternally transmitted haplotype, which had resulted in two novel HLA haplotypes in the proband. Conclusion:A rare case with simultaneous recombination of the paternal and maternal HLA- A/ C loci has been discovered, which may facilitate further study of the mechanisms of the HLA recombination.

Objective To systematically evaluate the risk factors associated with the occurrence of nosocomial infections(NI)in patients undergoing extracorporeal membrane oxygenation(ECMO)support.Methods A computerized systematic search was performed aross the Chinese databases including CNKI,Wanfang Database,China Biomedical Literature Database(CBMdisc),and Weipu,as well as the English databases such as PubMed,EMBase,Web of Science,and the Cochrane Library for case-control or cohort studies on the risk factors of hospital-acquired infections in patients undergoing ECMO support from the time of database construction to February 2023.The relevant literatures were screened by two researchers independently.Meta-analysis was performed using RevMan 5.4 software.Results A total of 20 papers,including 2 746 patients and 16 risk factors,were included.Meta-analysis results showed that older age[>50 years:odds ratio(OR)= 2.87,95％ confidence interval(95％ CI)was 1.24-6.63,P = 0.01;>65 years:OR = 1.66,95％ CI was 1.22-2.26,P = 0.001],combined hypertension(OR = 1.48,95％ CI was 1.01-2.15,P = 0.04),combined diabetes mellitus(OR = 1.40,95％ CI was 1.02-1.94,P = 0.04),sequential organ failure assessment(SOFA)was higher(OR = 1.06,95％ CI was 1.02-1.10,P = 0.000 7),the installation of ECMO in the intensive care unit(ICU,OR=1.48,95％ Ciwas 1.11-1.99,P=0.008),ECMO course(OR=1.27,95％ Ciwas 1.05-1.54,P = 0.01),ventilator-assistance for >48 hours(OR = 4.91,95％ CI was 2.40-10.05,P<0.000 1),and tracheotomy(OR = 9.56,95％ CI was 3.60-25.35,P<0.000 01)were identified as ECMO risk factors for hospital-acquired infections in patients.Conclusion Older age,combined hypertension,diabetes mellitus,higher SOFA,ECMO installation site in ICU,ECMO course,ventilator assistance>48 hours,tracheotomy are the risk factors for the occurrence of hospital-acquired infections in patients with ECMO,healthcare professionals should promptly identify the risk factors related to hospital-acquired infections,and take active and effective measures against controllable risk factors,including early intervention to prevent the occurrence of NI in ECMO patients.

【Objective】 To analyze the commonality and characteristics between voluntary blood donors and hematopoietic stem cell donors in this region, and explore the potential for integration and development between China Marrow Donors Program (CMDP) and voluntary blood donors, especially platelet donor databases, so as to improve recruitment success rate and inventory rate. 【Methods】 The database modeling and comparison methods were used to screen and stratify the matching and integration degree between the voluntary blood donors in recent 10 years and the marrow donors in the Shaanxi Branch of CMDP. The frequencies of HLA-A,-B alleles, HPA alleles and haplotypes were calculated with Arlequin 3. 5. 2. 2 software, and the matching probability of different platelet donor reserve pools was conducted according to the phenotypic frequencies. 【Results】 Among the voluntary donors with known HLA genotypes in this region, according to their blood donation behavior,the active blood donors excavated were divided into the first, second, third and fourth echelons of platelet donor reserve pools, with 696, 2 752, 9 092 and 12 028 donors, respectively. The first echelon had the highest proportion of 10-50 times of platelet donations and 10-20 times of whole blood donations, with 13.65% and 26.01%, respectively. The second echelon had 10-20 times of whole blood donations and 10-50 times of platelet donations, accounted for 15.04% and 1.38%, respectively, which were significantly different from other echelons' blood donation characteristics (P<0.05). With a database size of the existing platelet donor bank adding the first and second echelons (n=4 955), there was a 69.02% probability of matching at least one donor with matching HLA-A-B phenotype. When considering the matching ABO and HPA phenotypes, the probability of finding at least one donor with fully matching HLA, HPA and ABO isotype (type B as an example) was 48. 73%. 【Conclusion】 The three groups of whole blood donation, apheresis platelet donation and marrow donation in Xi'an area have a large cross-distribution. Compared with expanding the storage capacity from scratch, the active blood donors in CMDP database are the largest back-up force of platelet donors. While expanding the effective storage capacity, it can minimize the cost of building platelet donor bank and the demand for resources.

【Objective】 To evaluate the appropriate optimal capacity and matching probability of the platelet donor database with known HLA/HPA genotype in Shaanxi aera, and provide data support for subsequent construction, maintenance and application of the local platelet donor database. 【Methods】 A total of 11 755 individuals from the Shaanxi Branch of China Marrow Donor Program, 401 and 249 unrelated random platelet donors in Shaanxi aera were enrolled to the population study of HLA-A, -B polymorphisms, HPA genotyping and CD36 antigen expression, respectively. The frequencies of HLA-A, -B alleles, HPA alleles and haplotypes were calculated with Arlequin 3. 5. 2. 2 software; matching probability and capacity evaluation of platelet donor database was conducted according to the phenotypic frequencies. 【Results】 The population genetic and phenotypic polymorphisms data of HLA-A, -B and HPA1-6, 10, 15, 21 in Shaanxi aera were obtained. The frequency of CD36 type Ⅰ or Ⅱ deficiency was 0.40%(1/249). According to the subsequent calculating and deriving, with a database size of 194 donors, the patient having approximate 95% probability could achieve matching of HPA1-6, 10, 15, 21 genotype. With a database size of 1500 donors, there is a 95% probability of matching at least one donor with HLA-A-B phenotype frequency >0.002 or haplotype frequency >0.001; meanwhile, the probability of matching a cross-reactive group donor should be 44.95%-97.57%. Based on database size of 8 856 and 15 033, the probabilities of matching HLA-A, -B phenotype were about 80% and 90%, respectively. 【Conclusion】 The differences in the distribution of HLA/HPA polymorphism in different regions make the establishment mode and optimal capacity of platelet donor database different. It is necessary to apply a variety of platelet matching transfusion strategies to expand the range of donor selection, thereby effectively reducing the database construction cost and resource requirements.

OBJECTIVE: To verify a rare allele of human leukocyte antigen (HLA) and analyze its inheritance and 3D molecular structure. METHODS: PCR-sequence-based typing, PCR-single strand oligonucleotide polymorphism and single allele-specific sequencing were carried out to characterize the rare HLA-C allele and its transmission in the family. Its protein structure was modeled by using SWISS-MODEL, Phyre2 and FATCAT software. RESULTS: Analysis indicated that the rare allele (HLA-C*08:84) has transmitted from the proband's mother and has differed from HLA-C*08:01 by a single base (g.512G>C), resulting in substitution of an amino acid (p.Trp147Ser). Modeling of the 3D structure of the encoded protein indicated that the amino acid residue variation is located at the alpha 2 helix, which participates the formation of pocket F. Modeling of the structures of C*08:84, C*08:01, C*08:02, C*08:03 and C*08:22 has suggested significant variation in the peptide binding regions of the backbone, with root mean square errors being 1.70 nm, 1.79 nm, 0.71 nm and 1.70 nm, respectively. CONCLUSION A rare HLA-C*08:84 allele has been identified, and its clinical significance has been analyzed.
Alleles ; Base Sequence ; HLA-B Antigens/genetics* ; HLA-C Antigens/genetics* ; Humans ; Molecular Structure ; Sequence Analysis, DNA

【Objective】 To explore the association of HLAII(-DRB1, -DQB1, -DPB1) alleles and haplotypes polymorphisms with acute myeloid leukemia (AML) in northern Han population. 【Methods】 A total of 308 AML (non-M3) patients (patient group) and 824 unrelated healthy bone marrow donors (control group) were genotyped at a high-resolution level using polymerase chain reaction-sequence-based typing (PCR-SBT), next-generation sequencing (NGS) with Ion Torrent S5 platform and sequence specific oligonueleotide probes (SSO) with LABScan^® 3D platform. Frequencies of HLA II alleles and haplotypes were calculated with Arlequin 3.5.2.2 software. The odds ratio (OR) of AML was also calculated for case-control study. 【Results】 By χ² test and correction, an increased frequency of HLA-DRB1^*07∶01(14.61% vs 9.53%, P<0.01), HLA-DQB1^*02∶02(12.82% vs 8.31%, P<0.01), HLA-DQB1^*06∶02(11.53% vs 8.74%, P<0.05) and HLA-DPB1^*17∶01(5.84% vs 3.16%, P<0.01) among AML patients was discovered in significant comparison with the control group. After Bonferroni correction, the frequency of HLA-DRB1^*07∶01(Pc<0.05), HLA-DQB1^*02: 02(Pc<0.05) and HLA-DPB1^*17∶01(Pc<0.05) in AML patients were still higher than those in the control group, which had a strong positive correlation with AML (OR=1.62 (95% CI=1.23~2.14), 1.62(95% CI=1.21~2.18) and 1.91(95% CI=1.23~2.94), respectively. The frequency of two loci haplotype HLA-DRB1^*07∶01-DQB1^*02∶02 in AML patients was still higher than that of the control group after Bonferroni correction (12.66% vs 8.19%, Pc<0.05). The frequency of the 3 loci haplotype HLA-DRB1^*07∶01-DQB1^*02∶02-DPB1^*17∶01, as a susceptible haplotype of AML, was higher than that of the control group and was strongly correlated with AML. 【Conclusion】 The data on the association of HLA II (-DRB1, -DQB1, -DPB1) alleles and haplotype polymorphisms with AML in northern Han populations was obtained in this study. HLA-DRB1^*07∶01, HLA-DQB1^*02∶02, HLA-DPB1^*17∶01 and the HLA-DRB1^*07∶01-DQB1^*02∶02-DPB1^*17∶01 haplotype are the risk genes and susceptible extended haplotype for AML. The risk prediction based on HLA haplotype might be more accurate than that based on single allele.

OBJECTIVETo assess the association of polymorphisms of human leukocyte antigen (HLA)-A, -B, -DRB1 alleles and haplotypes with acute lymphoblastic leukemia (ALL) among ethnic Hans from northern China.

METHODSA total of 170 ALL patients (patient group) and 1241 unrelated healthy bone marrow donors (control group) were genotyped at a high-resolution level using polymerase chain reaction-sequence-based typing (PCR-SBT), sequence specific oligonucleotide probes (SSO) and sequence specific primer (SSP) typing methods. Frequencies of HLA alleles and haplotypes were calculated with Arlequin 3.5.2 software. The distribution of genes and haplotypes were analyzed through a case-control study, and the odd ratio (OR) of ALL was also calculated.

RESULTSBy cha-square test and correction, an increased frequency of B*13:01 and B*40:02 among ALL patients was discovered in comparison with the controls (7.35% vs. 4.63%, P=0.030; 2.94% vs. 1.45%, P=0.042), whereas B*35:03 and B*46:01 were less frequent compared with the controls (0.29% vs. 1.69%, P=0.048; 4.41% vs. 7.82%, P=0.025). Although the above discrepancies were not statistically significant by Bonferroni correction, within DRB1*15 group, the frequency of DRB1*15:01 in ALL patients was significantly greater than that of the controls (16.18% vs. 10.19%, Pc'=0.041) and was correlated with ALL (OR=1.70, 95% CI:1.24-2.33). Nineteen haplotypes identified in the ALL patients had a frequency greater than those of the controls. Of these, 11 were absent from the control group and were correlated with ALL.

CONCLUSIONThe association of HLA-A, -B, -DRB1 polymorphisms with ALL was determined among patients from northern Chinese Hans. The correlation between DRB1*15:01 and ALL suggested that DRB1*15:01 may be a susceptibility gene for ALL with its particular haplotypes.

Adolescent ; Adult ; Alleles ; Case-Control Studies ; Child ; Child, Preschool ; Female ; HLA-A Antigens ; genetics ; HLA-B Antigens ; genetics ; HLA-DRB1 Chains ; genetics ; Haplotypes ; Humans ; Infant ; Male ; Middle Aged ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; Young Adult