Objective: To establish a method for the genotyping of fetal M blood group antigen by extracting cell-free fetal DNA (cff-DNA) from maternal plasma, so as to guide the management of M antigen-negative pregnant women with IgG anti-M antibody during pregnancy. Methods: A realtime fluorescent quantitative PCR (realtime PCR) method was established. The specificity and sensitivity of the method were validated by dilution of genomic DNA. Subsequently, a total of 12 M antigen-negative pregnant women were enrolled. The cff-DNA was extracted from maternal plasma, and fetal M antigen genotyping was performed by realtime PCR. Fetuses were classified as M-positive or M-negative according to the presence or absence of amplification curve. The accuracy of the method was validated by comparing fetal M antigen genotyping results with the serological results using the cord or peripheral blood of the neonate at birth. Results: Among the 12 M antigen-negative pregnant women, anti-M was detected in five cases, of which four cases had IgG anti-M, and one case had fetal anemia. The results of fetal M antigen genotyping showed that 9 cases were M-positive (9/12, 75%) and 3 cases were M-negative (3/12, 25%). Serological results of blood samples collected after birth from four M-positive fetuses and one M-negative fetus were consistent with the genotyping results. Conclusion: We have, for the first time, established a non-invasive prenatal genotyping method for fetal M antigen using maternal plasma cff-DNA, and preliminarily demonstrated the feasibility of this method.

Objective: To conduct screening for rare blood types within important blood group systems for the Chinese population, such as Rh, Duffy, Kidd, P1Pk, Diego, and MNS, in the Guangzhou region, and to establish a corresponding rare blood type database and physical repository. Methods: The saline medium microplate method was used to screen blood donors with the ccDEE phenotype combined with either Jk(a-) or Jk(b-). The polybrene microplate method was employed to screen for donors with Fy(a-), s(-), Lu(b-), Di(b-), k(-), and p phenotypes. The urea lysis microplate method was applied to screen for the Jk(a-b-) phenotype. A high-resolution melting (HRM) curve method was established for screening some donors with the Di(b-) phenotype. Subsequently, expanded phenotyping of antigens in the Rh, Kidd, MNS, Duffy, P1Pk, Lewis, Kell, and Lutheran blood group systems was performed on identified rare blood type donors using monoclonal antibodies. The test results are entered into the Rare Blood Type Bank Management System of the Guangzhou Blood Center, enabling functions such as confirmation reminders and cryopreservation storage when the donor donates again. Red blood cells of rare blood types are processed into frozen red blood cells for long-term storage. Results: Among voluntary blood donors, 16 cases of the ccDEE combined with Jk(a-) phenotype were identified (0.221 7%, 16/7 216); 10 cases of the ccDEE combined with Jk(b-) phenotype (0.138 6%, 10/7 216); 78 cases of the Fy(a-) phenotype (0.169 5%, 78/46 012); 39 cases of the Lu(b-) phenotype (0.138 2%, 39/28 214); 31 cases of the s(-) phenotype (0.081 8%, 31/37 913); 22 cases of the Di(b-) phenotype (0.029 9%, 22/73 691); 30 cases of the Jk(a-b-) phenotype (0.010 1%, 30/298 250); and 1 case of the k(-) phenotype (0.001 3%, 1/77 382), which was further identified as KELnull phenotype (K0). No p phenotype donors were identified (0/88 528). A total of 228 units of frozen red blood cells were prepared. The screening results were compared and analyzed with rare blood type data from other regions. Conclusion: This study, through a combination of different screening methods, significantly improved the efficiency of rare blood type screening while remaining cost-effective. By conducting large-scale screening and performing data informatization processing, a database and physical repository of rare blood types in the Guangzhou region were successfully established. This provides a strong guarantee for the timely supply of blood to patients with difficult-to-match and rare blood types in the region, effectively enhances the level of transfusion safety in the region, and offers a practical paradigm for constructing a comprehensive blood transfusion support system.

Objective:This study investigated the expression of C-X-C motif chemokine receptor 3 (CXCR3) on CD45RO? T cells in the peripheral blood of patients with Alzheimer′s disease (AD) and its association with clinical features.Methods:A total of 41 AD patients and 30 age-and sex-matched healthy controls (HCs) were recruited from the Department of Neurology at the Medical Division of PLA General Hospital between September 2022 and March 2024. Flow cytometry was used to quantify CXCR3 expression on CD45RO? T cell subsets in peripheral blood. Dementia severity in AD patients was assessed using the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). Spearman correlation analysis examined the relationship between CD45RO?CXCR3? T cell levels and cognitive function in the AD group. Receiver operating characteristic (ROC) curve analysis determined the predictive utility of CD45RO?CXCR3? T cells for AD, quantified by the area under the curve (AUC).Results:Compared to healthy controls, AD patients exhibited significantly elevated levels of CD8?CD45RO?CXCR3? T cells [17.8% (7.2%, 40.3%) vs. 8.2% (5.1%, 12.3%), Z=-2.59, P<0.05]. However, no significant differences were observed for CD4?CD45RO?CXCR3? T cells, CD4?CD45RO?CXCR3? T cells, or CD8?CD45RO?CXCR3? T cells ( P>0.05). Spearman correlation analysis revealed a negative correlation between CD8?CD45RO?CXCR3? T cell levels and cognitive scores (MMSE: r=-0.72, P<0.05; MoCA: r=-0.70, P<0.05). ROC analysis demonstrated an AUC of 0.81 for CD8?CD45RO?CXCR3? T cells in predicting AD, with a sensitivity of 59.0% and specificity of 93.3%. Conclusions:CXCR3 expression is significantly upregulated on CD8?CD45RO? T cells in AD patients, and its levels correlate with cognitive impairment severity. These findings suggest that CD8?CD45RO?CXCR3? T cells may serve as a potential biomarker for AD diagnosis and progression monitoring.

Objective: To investigate the distribution of GP (B-A-B) hybrid glycophorins in several Chinese minority populations from southern regions of China (Guangdong & Guizhou). Methods: Whole blood samples were collected from 536 blood donors representing 15 different Chinese ethnic minority groups, including She, Bouyei, Yi and Miao, as well as Chuanqing populations. Genomic DNA was extracted and GYP (B-A-B) genotyping was conducted by high resolution melting (HRM) minority method using the GYPB pseudoexon 3-specific primers. Direct sequencing of GYPB pseudoexon 3 was performed in the samples with variant curves. Results: Only one genotype of GP (B-A-B) hybrid glycophorins (GYP Mur/GYPB) was identified among these 536 samples. In total, 15 She (15/162, 9.26%), 18 Bouyei (18/113, 15.93%), 3 Yi (3/79, 3.80%), 3 Chuanqing (3/45, 6.67%), 2 Bai (2/42, 4.76%), 3 Miao (3/40, 7.50%), 1 Shui (1/12, 8.33%), 2 Gelao (2/12, 16.67%), 1 Tujia (1/8, 12.50%) and 1 Dong (1/6, 16.67%) blood donors with heterozygous GYP Mur allele were identified. Among 8 Hui, 5 Manchu, 2 Mongolian, 1 Yao and 1 Li donors, no GYP (B-A-B) hybrid gene carrier was found. In addition, four nucleotide polymorphisms (SNPs) were identified in 6 samples with a variant melting curve detected by HRM. Conclusion: GP. Mur is the most common type of GP (B-A-B) hybrid glycophorins among Chinese minority populations, with frequency varying across different populations. It is recommended to involve GP. Mur reagent cells in the antibody screening cells for populations with a high frequency of GYP Mur allele.

Objective:This study investigated the expression of C-X-C motif chemokine receptor 3 (CXCR3) on CD45RO? T cells in the peripheral blood of patients with Alzheimer′s disease (AD) and its association with clinical features.Methods:A total of 41 AD patients and 30 age-and sex-matched healthy controls (HCs) were recruited from the Department of Neurology at the Medical Division of PLA General Hospital between September 2022 and March 2024. Flow cytometry was used to quantify CXCR3 expression on CD45RO? T cell subsets in peripheral blood. Dementia severity in AD patients was assessed using the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). Spearman correlation analysis examined the relationship between CD45RO?CXCR3? T cell levels and cognitive function in the AD group. Receiver operating characteristic (ROC) curve analysis determined the predictive utility of CD45RO?CXCR3? T cells for AD, quantified by the area under the curve (AUC).Results:Compared to healthy controls, AD patients exhibited significantly elevated levels of CD8?CD45RO?CXCR3? T cells [17.8% (7.2%, 40.3%) vs. 8.2% (5.1%, 12.3%), Z=-2.59, P<0.05]. However, no significant differences were observed for CD4?CD45RO?CXCR3? T cells, CD4?CD45RO?CXCR3? T cells, or CD8?CD45RO?CXCR3? T cells ( P>0.05). Spearman correlation analysis revealed a negative correlation between CD8?CD45RO?CXCR3? T cell levels and cognitive scores (MMSE: r=-0.72, P<0.05; MoCA: r=-0.70, P<0.05). ROC analysis demonstrated an AUC of 0.81 for CD8?CD45RO?CXCR3? T cells in predicting AD, with a sensitivity of 59.0% and specificity of 93.3%. Conclusions:CXCR3 expression is significantly upregulated on CD8?CD45RO? T cells in AD patients, and its levels correlate with cognitive impairment severity. These findings suggest that CD8?CD45RO?CXCR3? T cells may serve as a potential biomarker for AD diagnosis and progression monitoring.

[Abstract] [Objective] To further identify the RhD phenotype and RHD genotype in the individual who have RhD negative phenotype in the primary screening, and to analyze the effect of c. 801+2T>G mutation on RhD phenotype by minigene splicing assay. [Methods] The serologic test was performed for RhD phenotype identification and absorption-elution test was performed by using monoclonal anti-D. Sanger sequencing was used to analyze the sequence of RHD genes and the newly identified splicing site mutations of RHD genes were used to construct pSplicePOLR2G micro gene expression plasmids. By using an in vitro micro gene splicing system, the mRNA splicing results were detected and analyzed using agarose and capillary electrophoresis to predict their impact on RhD phenotype. [Results] The serological test results showed that the patient's blood type was RhD-negative, but the anti-D absorption-elution test was positive, indicating a Del phenotype. The rare genotype RHD^*(1227A/801+2G) was identified in this individual. The c. 801+2T>G was a novel mutation at 5'-splice site of intron 5. The minigene splicing assay showed that c. 801+2T>G resulted in a complete skipping of RHD exon 5 in the mature transcript, forming a transcript without exon 5. [Conclusion] An individual carrying a novel mutation c. 801+2T>G in the RHD gene was found to exhibit a Del phenotype, but also carry the Asian Del allele c. 1227G>A. It was speculated that the c. 801+2T>G mutation caused RhD negative or Del phenotype based on the results of minigene splicing assay in vitro.

Objective To elucidate the prediction ability of monocyte monolayer assay(MMA)used in hemolytic dis-ease of fetus and newborn(HDFN)caused by IgG anti-M.Methods Plasma from eight pregnant women containing IgG an-ti-M were collected,and were divided into two groups(4 cases with HDFN,with severe clinical symptoms such as fetal hy-drops,and 4 cases without HDFN)according to the clinical outcomes.M antigen positive cells were sensitized with dithioth-reitol(DTT)treated plasma from eight pregnant women respectively.MMA was performed by coincubation with monocytes and sensitized M cells,along with negative and positive control set up.T-test was conducted to compare the difference in phagocytic efficiency between two groups.Results The phagocytic efficiency in group with HDFN were 15.37%,13.05%,9.17%and 24.50%respectively,with the mean value of 15.52%,while the group without HDFN were 8.74%,11.07%,5.12%and 6.23%respectively,with the mean value of 7.79%.There was no significant difference in phagocytic efficiency between two groups(P>0.05).The mean values of both groups were not significantly different from the negative control(P>0.05),but both were significantly lower than positive control(P<0.05).Conclusion The low phagocytic efficiency couldn't convince that the MMA is an effective predictor for the HDFN caused by IgG anti-M,indicating that another mech-anism might be responsible for it rather than monocyte phagocytosis.The assessment of the peak systolic velocity in middle cerebral artery of the fetal should be considered in the management for pregnant women who produce IgG anti-M to estimate the situation of fetal anemia.

【Objective】 To identify the specificity of alloantibody against high-frequency antigens in one case suffering with severe hemolytic diseases of the fetus and newborn (HDFN) and to screen for matching blood for transfusion. 【Methods】 The HDFN test and the antibody serological identification tests in the mother were performed. Several common high frequency antigens of maternal red blood cells (RBCs) were determined. IgG subtype coated on the RBCs of the newborn was determined. The phagocytic efficiency of the antibody was tested using the monocyte phagocytosis of sensitized erythrocyte by flow cytometry in vitro. Sanger sequencing of DI gene was performed in the mother, father and mother’s brother. The diluted maternal plasma was used for large scale screening of matching blood using IAT in Coomb’s gel card. 【Results】 Di(b-) phenotype was identified in the mother of the newborn and anti-Di^b (titer: 512) related HDN was detected in the newborn. IgG1 and IgG2 subtypes of anti-Di^b were detected and the rate of monocyte phagocytosis was 88.83%(74.7/84.09). The compatible blood was not detected in the maternal relatives. Subsequently, the newborn received the matching RBCs of two Di(b-) donors identified from 5 520 blood donors and discharged from the hospital. We screened out 17 Di(b-) donors out of 51 334 blood donors, indicating that the distribution frequency of Di(b-) among blood donors in Guangzhou was about 0.033% (17/51 334). 【Conclusion】 By serology and molecular biology methods, the newborn was identified with HDFN caused by anti-Di^b, and an effective large-scale screening method for Di (b -) rare blood types was established to find matching blood, which supported the establishment of rare Di(b-) blood database.

Objective:To investigate the correlation of cognitive dysfunction with intracranial lesions and symptoms of depression and anxiety in patients with neuromyelitis optica spectrum disorders (NMOSD).Methods:Thirty-one NMOSD patients (7/24 males/females) were enrolled in the Department of Neurology of the Sixth Medical Center of the PLA General Hospital from August 2019 to August 2022. The average age was 42±13 years, and the average education level was 12 (9, 12) years. There were 30 healthy controls, 11/19 males/females, with an average age of 47±9 years and an average education of 12 (9, 15) years. The general clinical data and imaging data were collected, and the subjects were assessed on their cognition, anxiety and depression using the assessment scale approved at home and abroad. A cross-sectional study was conducted on them. The t-test or Wilcoxon test was used for inter-group comparison, and Pearson test or Spearman test was used to explore the correlation between the cognition of NMOSD patients and their intracranial lesions, depression and anxiety. Results:Compared with the healthy control group, NMOSD patients had significantly lower scores on MoCA ( Z=-3.10, P=0.002), CRAVLT-N7 ( Z=-5.12, P<0.001), CRAVLT-N8 ( t=-4.40, P<0.001), ROCF-R ( t=-3.10, P<0.01), ROCF-C ( Z=-2.72, P<0.01), PASAT-3 ( Z=-2.71, P<0.01), PASAT-2 ( Z=-3.14, P<0.01), and CWT-A ( Z=-3.10, P<0.01)scales. Frontal lobe lesions were negatively correlated with PASAT-2 ( r=-0.448, P=0.012) scores, temporal lobe lesions were negatively correlated with CRAVLT-N9 ( r=-0.564, P=0.001), and parietal lobe lesions were negatively correlated with MoCA ( r=-0.374, P=0.038), PASAT-3 ( r=-0.426, P=0.017), and PASAT-2 ( r=-0.459, P=0.009) scores; The scores of MoCA ( r=-0.392, P=0.029), CRAVLT-N6 ( r=-0.396, P=0.028), CRAVLT-N7 ( r=-0.415, P=0.020), CRAVLT-N8 ( r=-0.406, P=0.023), PASAT-3 ( r=-0.537, P=0.002) and PASAT-2 ( r=-0.495, P=0.005) scales were negatively correlated with the scores of HAMD assessment, and the scores of PASAT-3 ( r=-0.499, P=0.004) and PASAT-2 ( r=-0.452, P=0.011) were negatively correlated with the scores of HAMA. Conclusions:The cognitive function of patients with NMOSD is significantly reduced, involving multiple cognitive domains. The cognitive function is affected by the distribution of intracranial lesions and the degree of depression and anxiety.

【Objective】 To study the effect of RHAG variants identified in Chinese population on mRNA splicing by minigene splicing assay(MSA) in vitro. 【Methods】 The pSplicePOLR2G minigene expression plasmids were constructed for 10 RHAG mutations with relatively high distribution frequency in Chinese population near splicing sites or synonymous mutations by analyzing the RHAG gene data in the KMxD database. Then, the wild-type and mutant plasmids were transfected into HEK 293T cells, and RNA was extracted 48 hours after transfection. After reverse transcription, specific primers were used for PCR amplification, and then agarose gel electrophoresis and capillary electrophoresis were performed to determine whether the mutations will affect the normal splicing of exons. 【Results】 MSA in vitro showed that 2 mutations (c.158-5delT, c. 807+ 3A>C) near the splicing site reduced the amount of normal transcripts slightly. The remaining 8 synonymous mutations(c.312G>A, c. 341+ 3G>A, c. 609C>T, c. 681G>A, c. 861G>A, c. 957T>A, c. 984T>C and c. 1139-7G>A) had no impact on the splicing of RHAG mRNA. 【Conclusion】 This study showed that RHAG gene was conservative in terms of splicing, and the mutations near splicing sites and synonymous mutations were less likely to cause abnormal splicing of RHAG gene.