Infant Gut Microbial Metagenome Mining of α-l-Fucosidases with Activity on Fucosylated Human Milk Oligosaccharides and Glycoconjugates.

The gastrointestinal microbiota members produce α-l-fucosidases that play key roles in mucosal, human milk, and dietary oligosaccharide assimilation. Here, 36 open reading frames (ORFs) coding for putative α-l-fucosidases belonging to glycosyl hydrolase family 29 (GH29) were identified through metagenome analysis of breast-fed infant fecal microbiome. Twenty-two of those ORFs showed a complete coding sequence with deduced amino acid sequences displaying the highest degree of identity with α-l-fucosidases from Bacteroides thetaiotaomicron, Bacteroides caccae, Phocaeicola vulgatus, Phocaeicola dorei, Ruminococcus gnavus, and Streptococcus parasanguinis. Based on sequence homology, 10 α-l-fucosidase genes were selected for substrate specificity characterization. The α-l-fucosidases Fuc18, Fuc19A, Fuc35B, Fuc39, and Fuc1584 showed hydrolytic activity on α1,3/4-linked fucose present in Lewis blood antigens and the human milk oligosaccharide (HMO) 3-fucosyllactose. In addition, Fuc1584 also hydrolyzed fucosyl-α-1,6-N-acetylglucosamine (6FN), a component of the core fucosylation of N-glycans. Fuc35A and Fuc193 showed activity on α1,2/3/4/6 linkages from H type-2, Lewis blood antigens, HMOs and 6FN. Fuc30 displayed activity only on α1,6-linked l-fucose, and Fuc5372 showed a preference for α1,2 linkages. Fuc2358 exhibited a broad substrate specificity releasing l-fucose from all the tested free histo-blood group antigens, HMOs, and 6FN. This latest enzyme also displayed activity in glycoconjugates carrying lacto-N-fucopentaose II (Lea) and lacto-N-fucopentaose III (Lex) and in the glycoprotein mucin. Fuc18, Fuc19A, and Fuc39 also removed l-fucose from neoglycoproteins and human α-1 acid glycoprotein. These results give insight into the great diversity of α-l-fucosidases from the infant gut microbiota, thus supporting the hypothesis that fucosylated glycans are crucial for shaping the newborn microbiota composition. IMPORTANCE α-l-Fucosyl residues are frequently present in many relevant glycans, such as human milk oligosaccharides (HMOs), histo-blood group antigens (HBGAs), and epitopes on cell surface glycoconjugate receptors. These fucosylated glycans are involved in a number of mammalian physiological processes, including adhesion of pathogens and immune responses. The modulation of l-fucose content in such processes may provide new insights and knowledge regarding molecular interactions and may help to devise new therapeutic strategies. Microbial α-l-fucosidases are exoglycosidases that remove α-l-fucosyl residues from free oligosaccharides and glycoconjugates and can be also used in transglycosylation reactions to synthesize oligosaccharides. In this work, α-l-fucosidases from the GH29 family were identified and characterized from the metagenome of fecal samples of breastfed infants. These enzymes showed different substrate specificities toward HMOs, HBGAs, naturally occurring glycoproteins, and neoglycoproteins. These novel glycosidase enzymes from the breast-fed infant gut microbiota, which resulted in a good source of α-l-fucosidases, have great biotechnological potential.

Development of high-throughput UPLC-MS/MS using multiple reaction monitoring for quantitation of complex human milk oligosaccharides and application to large population survey of secretor status and Lewis blood group.

Human milk oligosaccharides (HMOs) have attracted increasing attention due to the emerging evidence of their positive roles for infant's health. A high-throughput method for absolute quantitation of the complex HMOs including multiple isomeric structures is important but very challenging, due to the highly divers nature and wide variation in content of HMOs from different individuals. Here we used UPLC-MS-MRM in the negative-ion mode for accurate quantitation of 23 complex HMOs in just 15 min. The selected oligosaccharides are in their native forms and include neutral and sialylated, fucosylated and non-fucosylated, linear and branched, and secretor and Lewis phenotype indicators. The well validated method with good sensitivity, recovery and reproducibility was then applied to a large population quantitative survey of 251 Chinese mothers from five different ethnic groups (Han, Zhuang, Hui, Mongolian and Tibetan) living in different geographical regions for their secretor's status and Lewis phenotypes.

Dynamic and features of SARS-CoV-2 infection in Gabon.

In a context where SARS-CoV-2 population-wide testing is implemented, clinical features and antibody response in those infected have never been documented in Africa. Yet, the information provided by analyzing data from population-wide testing is critical to understand the infection dynamics and devise control strategies. We described clinical features and assessed antibody response in people screened for SARS-CoV-2 infection. We analyzed data from a cohort of 3464 people that we molecularly screened for SARS-CoV-2 infection in our routine activity. We recorded people SARS-CoV-2 diagnosis, age, gender, blood types, white blood cells (WBC), symptoms, chronic disease status and time to SARS-CoV-2 RT-PCR conversion from positive to negative. We calculated the age-based distribution of SARS-CoV-2 infection, analyzed the proportion and the spectrum of COVID-19 severity. Furthermore, in a nested sub-study, we screened 83 COVID-19 patients and 319 contact-cases for anti-SARS-CoV-2 antibodies. Males and females accounted for respectively 51% and 49% of people screened. The studied population median and mean age were both 39 years. 592 out of 3464 people (17.2%) were diagnosed with SARS-CoV-2 infection with males and females representing, respectively, 53% and 47%. The median and mean ages of SARS-CoV-2 infected subjects were 37 and 38 years respectively. The lowest rate of infection (8%) was observed in the elderly (aged > 60). The rate of SARS-Cov-2 infection in both young (18-35 years old) and middle-aged adults (36-60 years old) was around 20%. The analysis of SARS-CoV-2 infection age distribution showed that middle-aged adults accounted for 54.7% of SARS-CoV-2 positive persons, followed respectively by young adults (33.7%), children (7.7%) and elderly (3.8%). 68% (N = 402) of SARS-CoV-2 infected persons were asymptomatic, 26.3% (N = 156) had influenza-like symptoms, 2.7% (N = 16) had influenza-like symptoms associated with anosmia and ageusia, 2% (N = 11) had dyspnea and 1% (N = 7) had respiratory failure, which resulted in death. Data also showed that 12% of SARS-CoV-2 infected subjects, had chronic diseases. Hypertension, diabetes, and asthma were the top concurrent chronic diseases representing respectively 58%, 25% and 12% of recorded chronic diseases. Half of SARS-CoV-2 RT-PCR positive patients were cured within 14 days following the initiation of the anti-COVID-19 treatment protocol. 78.3% of COVID-19 patients and 55% of SARS-CoV-2 RT-PCR confirmed negative contact-cases were positive for anti-SARS-CoV-2 antibodies. Patients with severe-to-critical illness have higher leukocytes, higher neutrophils and lower lymphocyte counts contrarily to asymptomatic patients and patients with mild-to-moderate illness. Neutrophilic leukopenia was more prevalent in asymptomatic patients and patients with mild-to-moderate disease for 4 weeks after diagnosis (27.1-42.1%). In Patients with severe-to-critical illness, neutrophilic leukocytosis or neutrophilia (35.6-50%) and lymphocytopenia (20-40%) were more frequent. More than 60% of participants were blood type O. It is also important to note that infection rate was slightly higher among A and B blood types compared with type O. In this African setting, young and middle-aged adults are most likely driving community transmission of COVID-19. The rate of critical disease is relatively low. The high rate of anti-SARS-CoV-2 antibodies observed in SARS-CoV-2 RT-PCR negative contact cases suggests that subclinical infection may have been overlooked in our setting.

Convalescent Plasma Therapy in the management of COVID-19 patients-The newer dimensions.

BACKGROUND: COVID 19 infection caused by novel coronavirus with no specific established treatment. Convalescent Plasma Therapy has been authorized as an off-label therapeutic procedure. We assessed the outcome of convalescent plasma (CP) units versus standard treatment on the complete recovery, improvement and 28 days' mortality of COVID 19 patients. MATERIALS AND METHODS: The present was multi-centric case controlled observational prospective study. The study was conducted for a period of four and half months from July 15 2020 to 30 November 2020 after taking approval from the Expert Committee, Health & Family Welfare Department, Government of Odisha. Plasma therapy was applied on two groups of 1189 serious COVID patients (959 number of pre- critical and 230 number of critical patients) not responding to oxygen therapy. It was compared with non- transfused control group of 1243 patients (996 number of pre-critical and 247 number of critical patients). RESULTS: Discharge was better in (55.5%) transfused than (43%)in non-transfused pre-critical patients and the mortality was lower (44.3%) in transfused, (48.9%) than non-transfused critical patients respectively. Complete recovery was highest in those who were transfused with CP with neutralizing titer more than 1:160 (52.5%), 18-30 years' age group (64%), females (53%), 'O' Rh D positive blood group (51.5%). There was no adverse reaction due to CP transfusion. CONCLUSIONS: CP is effective in improving the recovery rate with earlier discharge and decrease in the 28 days' mortality than in the control non-transfused group. CP with neutralizing antibody titer more than 1:160 has the best outcome with complete recovery and decrease in the mortality. It is more effective in treating pre-critical patients when transfused early, in female patients, in younger age group and in blood group 'O' Rh D positive.

Epidemiology of enteric virus infections in children living in the Amazon region.

OBJECTIVES: To verify the frequency of viruses causing acute gastroenteritis (AGE) in association with the histo-blood group antigen (HBGA) and Rotarix™ vaccination coverage in children from the Amazon region. DESIGN: Fecal and saliva samples were collected from children with AGE (n = 485) and acute respiratory infection (ARI) (n = 249) clinical symptoms. Rotavirus A (RVA), norovirus, human adenovirus (HAdV), and sapovirus (SaV) were verified in feces by molecular detection. Saliva samples were used for HBGA phenotyping/FUT3 genotyping. Blood group types, clinical aspects and Rotarix™ RVA vaccination data were recorded. RESULTS: Norovirus remained the most prevalently detected cause of AGE (38%, 184/485 and ARI 21.3%, 53/249). High HAdV frequencies were observed in AGE children (28.6%, 139/485) and ARI children (37.3%, 93/249). RVA was the third most prevalent virus causing AGE (22.7%, 110/485 and ARI 19.3%, 48/249) and a low RV1 coverage (61%, 448/734) was verified. The SaV frequencies were lower (7.2%, 35/485 for AGE and 6.8%, 17/249 for ARI). Secretor children were HBGA susceptible to HAdV infection (OR 1.5, 95% CI 1.0-2.3; P = 0.04) but not to RVA, norovirus or SaV infection. CONCLUSIONS: Norovirus could be considered the main etiological agent of AGE. No association was verified for HBGA susceptibility to RVA, norovirus and SaV. Secretor children showed a slight susceptibility to HAdV infection and the Le (a-b-) heterogeneous SNPs on the FUT3 gene.

Blood Groups and Hematological Parameters Do Not Associate with First Trimester Gestational Diabetes Mellitus (Institutional Experience).

OBJECTIVE: There are few published researches on blood groups, hematological parameters [hemoglobin, red cell distribution width (RDW), white blood cells (WBCs), mean platelets volume (MPV)] and gestational diabetes mellitus (GDM). The aim of this study was to investigate the association of haematological indices with GDM in early pregnancy. METHODS: The study was carried out at Saad Abuelela Hospital (Khartoum, Sudan) during March-November of 2018. Pregnant Sudanese women in early pregnancy (gestational age <14 weeks) were enrolled in the study. The details of the medical and obstetrics history were recorded. The women were then followed up until 24-28 weeks of gestation when a 75-gram oral glucose tolerance test was performed. RESULTS: Two hundred and fifty-three women at 10.2 week of gestational age completed the follow-up. The mean (SD) of the age and gravidity at the initial antenatal visit were 28.03 (5.6) years, 2.32 (2.41). The mean (SD) of body mass index (BMI) was 27.28 (24.41-30.80) kg/m2. Fifty women (19.8%) had GDM. Age, parity, BMI, place of residence, employment and education were not significantly different between the two groups. Moreover, there was no significant difference in the blood groups and hematological parameters between women with and without GDM. CONCLUSION: In this study, the blood groups and other hematological parameters were not different between women with and without GDM.

Chronic social stress lessens the metabolic effects induced by a high-fat diet.

Stress has a major impact on the modulation of metabolism, as previously evidenced by hyperglycemia following chronic social defeat (CSD) stress in mice. Although CSD-triggered metabolic dysregulation might predispose to pre-diabetic conditions, insulin sensitivity remained intact, and obesity did not develop, when animals were fed with a standard diet (SD). Here, we investigated whether a nutritional challenge, a high-fat diet (HFD), aggravates the metabolic phenotype and whether there are particularly sensitive time windows for the negative consequences of HFD exposure. Chronically stressed male mice and controls (CTRL) were kept under (i) SD-conditions, (ii) with HFD commencing post-CSD, or (iii) provided with HFD lasting throughout and after CSD. Under SD conditions, stress increased glucose levels early post-CSD. Both HFD regimens increased glucose levels in non-stressed mice but not in stressed mice. Nonetheless, when HFD was provided after CSD, stressed mice did not differ from controls in long-term body weight gain, fat tissue mass and plasma insulin, and leptin levels. In contrast, when HFD was continuously available, stressed mice displayed reduced body weight gain, lowered plasma levels of insulin and leptin, and reduced white adipose tissue weights as compared to their HFD-treated non-stressed controls. Interestingly, stress-induced adrenal hyperplasia and hypercortisolemia were observed in mice treated with SD and with HFD after CSD but not in stressed mice exposed to a continuous HFD treatment. The present work demonstrates that CSD can reduce HFD-induced metabolic dysregulation. Hence, HFD during stress may act beneficially, as comfort food, by decreasing stress-induced metabolic demands.

An open-source python library for detection of known and novel Kell, Duffy and Kidd variants from exome sequencing.

BACKGROUND AND OBJECTIVES: Next generation sequencing (NGS) has promising applications in transfusion medicine. Exome sequencing (ES) is increasingly used in the clinical setting, and blood group interpretation is an additional value that could be extracted from existing data sets. We provide the first release of an open-source software tailored for this purpose and describe its validation with three blood group systems. MATERIALS AND METHODS: The DTM-Tools algorithm was designed and used to analyse 1018 ES NGS files from the ClinSeq® cohort. Predictions were correlated with serology for 5 antigens in a subset of 108 blood samples. Discrepancies were investigated with alternative phenotyping and genotyping methods, including a long-read NGS platform. RESULTS: Of 116 genomic variants queried, those corresponding to 18 known KEL, FY and JK alleles were identified in this cohort. 596 additional exonic variants were identified KEL, ACKR1 and SLC14A1, including 58 predicted frameshifts. Software predictions were validated by serology in 108 participants; one case in the FY blood group and three cases in the JK blood group were discrepant. Investigation revealed that these discrepancies resulted from (1) clerical error, (2) serologic failure to detect weak antigenic expression and (3) a frameshift variant absent in blood group databases. CONCLUSION: DTM-Tools can be employed for rapid Kell, Duffy and Kidd blood group antigen prediction from existing ES data sets; for discrepancies detected in the validation data set, software predictions proved accurate. DTM-Tools is open-source and in continuous development.

Blood use and transfusion needs at a large health care system in Washington state during the SARS-CoV-2 pandemic.

BACKGROUND: This report evaluates hospital blood use trends during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, and identifies factors associated with the need for transfusion and risk of death in patients with coronavirus 2019 (COVID-19). METHODS: Overall hospital blood use and medical records of adult patients with COVID-19 were extracted for two institutions. Multivariate logistic regression models were conducted to estimate associations between the outcomes transfusion and mortality and patient factors. RESULTS: Daily blood use decreased compared to pre-COVID-19 levels; the effect was more significant for platelets (29% and 34%) compared to red blood cells (25% and 20%) at the two institutions, respectively. Surgical and oncologic services had a decrease in average daily use of platelets of 52% and 30%, and red blood cells of 39% and 25%, respectively. A total of 128 patients with COVID-19 were hospitalized, and 13 (10%) received at least one transfusion due to anemia secondary to chronic illness (n = 7), recent surgery (n = 3), and extracorporeal membrane oxygenation (n = 3). Lower baseline platelet count and admission to the intensive care unit were associated with increased risk of transfusion. The blood group distribution in patients with COVID-19 was 37% group O, 40% group A, 18% group B, and 5% group AB. Non-type O was not associated with increased risk of mortality. CONCLUSION: The response to the SARS-CoV-2 pandemic included changes in routine hospital operations that allowed for the provision of a sufficient level of care for patients with and without COVID-19. Although blood type may play a role in COVID-19 susceptibility, it did not seem to be associated with patient mortality.

Asymptomatic carriage of Plasmodium falciparum by individuals with variant blood groups and haemoglobin genotypes in southern Ghana.

BACKGROUND: The ABO and the Rhesus blood group systems, as well as various abnormal haemoglobin (Hb) variants (haemoglobinopathies) are known to influence malaria parasite carriage and disease severity in individuals living in malaria endemic areas. This study identified the blood group and Hb variant distribution and Plasmodium falciparum infection status of afebrile individuals living in southern Ghana. METHODS: Afebrile participants were recruited from Obom (358) in the Greater Accra Region and Ewim (100) and Simiw (329) in the Central Region of Ghana. Venous blood (1 ml) was collected into EDTA vacutainer tubes. Three 20 µl drops of blood were used for blood group analysis using the tile method. Another 500 µl aliquot was used for the qualitative sickling test using sodium metabisulphite and haemoglobin electrophoresis. Genomic DNA was extracted from 100 µl of whole blood and used in P. falciparum species-specific PCR. RESULTS: The most abundant blood group and abnormal haemoglobin variant in both sites was blood group O + (47.4%) and HbAS (15.8%). A total of 13 (1.7%) of the participants had full haemoglobinopathies (SS, SC and CC), whilst 196 (25.4%) were carriers (AS and AC). Although there was a significantly higher prevalence of sickling positive participants from the Central Region, genotyping identified a similar prevalence of each of the abnormal haemoglobin genes in both sites. Asymptomatic parasite carriage estimated by PCR was 40.9% in the Central Region and 41.8% in the Greater Accra Region. CONCLUSIONS: Asymptomatic carriage of P. falciparum parasite in the study population was not associated with any particular blood group variant or haemoglobin genotype.

Frecuencias de grupos sanguíneos de interés clínico en donantes y pacientes de Costa Rica / The frequency of blood groups of interest in donors and patients from Costa Rica

Introducción: Los sistemas sanguíneos ABO, Rh y Kell son lo más relevantes desde el punto de vista clínico por su inmunogenicidad y ser los principales causantes de reacciones hemolíticas. Objetivo: Determinar las frecuencias de los grupos sanguíneos ABO y Rh, y la frecuencia del antígeno Kell en pacientes y donantes de Costa Rica. Métodos: Durante el periodo de 2009 al 2018 se obtuvo de las bases de datos de los bancos de sangre de tres hospitales de adultos de Costa Rica, las frecuencias de los grupos sanguíneos ABO, Rh y Kell en muestras de donantes y pacientes. Para contrastar las frecuencias de cada grupo sanguíneo se realizó una prueba de independencia de variables Chi cuadrado, con el 95 por ciento de confianza. Los datos se analizaron con el paquete estadístico SPSS versión 23. Resultados: Las frecuencias de los grupos ABO en las muestras de donantes y pacientes mostraron diferencias pequeñas pero significativas. La frecuencia del fenotipo Rh D negativo fue más alta en pacientes (8,0 por ciento) que en donantes (6,1 por ciento). Se estimaron las frecuencias de los antígenos C (67,8 por ciento), c (80,5 por ciento), E (41,4 por ciento), e (94,4 por ciento) y K (3,1 por ciento) a partir de las muestras de los donantes. Conclusiones: Las estrategias de reclutamiento de donantes de sangre aumentan la frecuencia del fenotipo Rh negativo en donantes con respecto a los pacientes. Las estadísticas recopiladas demuestran un aumento en la frecuencia del grupo O en comparación con los últimos estudios relacionados. Finalmente, los otros antígenos presentaron pocas variaciones en comparación a estudios previos(AU)

Introduction: The ABO, Rh and Kell blood systems are the most relevant from the clinical point of view, due to their immunogenicity and because they are the main causes of hemolytic reactions. Objective: To determine the frequencies of ABO and Rh blood groups, and the frequency of the Kell antigen in patients and donors from Costa Rica. Methods: During the period from 2009 to 2018, the frequencies of ABO, Rh and Kell blood groups in donor and patient samples were obtained from the blood bank databases of three adult hospitals in Costa Rica. To contrast the frequencies of each blood group, a chi-square test of independence of variables was performed, with 95 percent confidence interval. The data were analyzed with the statistical package SPSS version 23. Results: The frequencies of ABO groups in donor and patient samples showed small but significant differences. The frequency of the negative Rh D phenotype was higher in patients (8.0 percent) than in donors (6.1 percent). The frequencies of the antigens C (67.8 percent), c (80.5 percent), E (41.4 percent), e (94.4 percent), and K (3.1 percent) were estimated from donor samples. Conclusions: Blood donor recruitment strategies increase the frequency of negative Rh phenotype in donors compared to patients. The statistics collected demonstrate an increase in the frequency of the O group compared to recent related studies. Finally, the other antigens did not show as much variation compared to previous studies(AU)

Epidemiology and HBGA-susceptibility investigation of a G9P[8] rotavirus outbreak in a school in Lechang, China.

Rotaviruses cause severe gastroenteritis in infants, in which the viruses interact with human histo-blood group antigens (HBGAs) as attachment and host susceptibility factors. While gastroenteritis outbreaks caused by rotaviruses are uncommon in adolescents, we reported here one that occurred in a middle school in China. Rectal swabs and saliva samples were collected from symptomatic and asymptomatic students, and samples were also collected from the environment. Using PCR, followed by DNA sequencing, a single G9P[8] rotavirus strain was identified as the causative agent. The attack rate of the outbreak was 13.5% for boarders, which was significantly higher than that of day students (1.8%). Person-to-person transmission was the most plausible transmission mode. The HBGA phenotypes of the individuals in the study were determined by enzyme immunoassay, using saliva samples, while recombinant VP8* protein of the causative rotavirus strain was produced for HBGA binding assays to evaluate the host susceptibility. Our data showed that secretor individuals had a significantly higher risk of infection than nonsecretors. Accordingly, the VP8* protein bound nearly all secretor saliva samples, but not those of nonsecretors, explaining the observed infection of secretor individuals only. This is the first single-outbreak-based investigation showing that P[8] rotavirus infected only secretors. Our investigation also suggests that health education of school students is an important countermeasure against an outbreak of communicable disease.

Fabrication of gelatin functionalized silver nanoparticles for blood group profiling.

We report the fabrication of silver nanoparticles (AgNPs) surface functionalized with gelatin at different concentrations (G10/G20/G40 AgNPs) with an average particle size of ∼200 nm, bioconjugated with antisera antibodies (AsAbs) of the major and clinically significant blood groups (CSBGs) at different titres from neat to 1:128. Bioconjugation using ionic interaction at pH 7.4 enabled 'end-on' configuration, with the -NH2 group of the antibody free for interaction with the red blood cell antigen, as confirmed by Fourier transform infrared spectroscopy. The tube agglutination test (TAT) revealed optimum agglutination with G20NPs, while SDS PAGE confirmed the optimal titre as 1:8 for the major blood groups A, B, AB and O. Bioconjugated AgNPs coated onto microtitre assay plates with the major blood groups and CSBGs to enable simultaneous identification, were validated against the TAT on 400 random blood samples for the major blood groups and revealed high accuracy (95%). While similar accuracy was seen for most of the CSBGs with only false negatives, the method was not found to be suitable for the Kell, Kidd and Duffy groups. The absence of false positives reflects high safety, and eliminates the risk of a mismatched blood transfusion. The method uses diluted blood and hence could enable point-of-care detection. The significantly lower AsAb requirement also provides a cost advantage.

Reliability of labeling red cell units with minor antigen historical results and process considerations.

BACKGROUND: Several approaches are used by blood centers when providing minor (non-ABO/D) antigen-negative RBCs to hospitals. Details vary but include providing results on the unit labeling intended for clinical use without retyping or providing results on packing documents or via computer query requiring confirmation. Recent regulatory changes allow labeling with historical minor antigen results, defined as previously performed by the donor center on two different donations with results linked to the donor and confirmed concordant. Here we investigate causes of discrepancies and identify critical process steps. STUDY DESIGN AND METHODS: Nine years (2009-2017) of data were reviewed for number, antigen system, and root cause of discrepancies flagged by the computer when retyping donors prior to labeling (internal discrepancies) or reported by the hospital when retested (external discrepancies). Licensed automated (CcEeK) and tube methods were used. RESULTS: Among 300,000 samples phenotyped for CcEe, K, Fya/b , Jka/b , Ss (>3 million antigens), ∼1,389,960 were repeated on 2nd donation with 397 (1/3501) discordant; 205 Fy, 118 Rh, and 74 others. Of ∼682,691 antigen-negative phenotypes provided on unit labeling, ∼37.5% (256,118) were retyped by hospitals with 29 discrepancies (1/8832), primarily Rh variants. CONCLUSION: When repeating minor antigen types by serology, discrepancies are primarily associated with weak Fyb , among Caucasian donors, and weak/partial Rh antigens in donors of African ancestry. DNA-based testing avoids these. To label with historical results, accuracy is increased by automated testing with direct computer interface. Testing on two donations with results confirmed to be concordant is not inferior to testing on the current donation.

Blood Group Types O and Non-O Are Associated With Coronary Collateral Circulation Development.

Blood group types are associated with coronary artery disease. However, data are scarce about the impact of blood group types on coronary collateral circulation. In this study, we aimed to investigate the relationship between the blood group types and coronary collateral circulation. Two hundred and twelve patients who underwent coronary angiography in our department and had a stenosis of ≥ 90% in at least one major epicardial vessel were included in our study. Collateral degree was graded according to Rentrop-Cohen classification. After grading, patients were divided into poor coronary collateral circulation (Rentrop grade 0 and 1) and good coronary collateral circulation (Rentrop 2 and 3) groups. The ABO blood type of all participants was determined. The incidence rates of O blood group type were significantly higher in the good coronary collateral group compared to the poor collateral group (37.9% vs 17.1%, P < .001). The O type blood group was an independent predictor of good coronary collateral circulation (odds ratio = 1.83, 95% confidence interval = 1.56-6.18, P = .015). Coronary collateral circulation is associated with blood group types. The O blood group predicts good coronary collateral development among patients with coronary artery disease.

A card agglutination test for dog erythrocyte antigen 1 (DEA 1) blood typing in donor dogs: Determining an appropriate cutoff to detect positivity using a receiver operating characteristic curve.

BACKGROUND: The appropriate cutoff to define a positive point-of-care card agglutination (CA) test for dog erythrocyte antigen 1 (DEA 1) blood typing depends on whether the test can be used in the donor or recipient. OBJECTIVES: By screening for CA test positivity, we aimed to evaluate the best cutoff value for DEA 1 blood typing in canine blood donors using a receiver operator characteristic (ROC) curve. METHODS: Ethylenediaminetetraacetic acid (EDTA) blood samples from 100 canine blood donors were blood-typed in parallel for DEA 1 using both immunochromatographic (IC) and CA tests. The effect of temperature, storage time, and anticoagulant solutions for both methods was evaluated. Unweighted and weighted Cohen's Kappa (K) statistic was calculated to evaluate the agreement between the two testing methods. The overall performance of the CA test was evaluated by generating a ROC curve using the IC test as the reference method. RESULTS: Concordant results were obtained for 86% of the samples. Unweighted and weighted K statistics demonstrated good and moderate agreement, respectively. For the CA test, the ROC curve showed an area under the curve (AUC) of 0.910, with the highest sensitivity cutoff values at ≥1+ agglutination. CA- and IC-typed EDTA blood samples stored at room temperature for up to 1 week and refrigerated for up to 1 month were concordant as were the citrate phosphate dextrose adenine 1 (CPDA-1) anticoagulated blood samples stored for up to 1 week at 4 ± 2°C. CONCLUSIONS: The overall reliability of the CA method seemed to be lower than that of the IC method. When CA is used as a screening test for canine blood donors, the correct cut off is ≥1+ agglutination is recommended to maximize sensitivity.

ID CORE XT as a tool for molecular red blood cell typing.

Introduction: Classic methods to determine human red blood cell (RBC) antigens are based on serologic testing, however there are some limitations. Based on these, several molecular techniques have been developed to bypass these restrictions and to detect the most important allelic variants, the last of great value for the approach in the personalized medicine, especially for patients in chronic transfusion regime. Areas covered: In this article, we provide an updated review of the ID CORE XT (Progenika Biopharma-Grifols, Bizkaia, Spain) that is one of the commercial DNA-based techniques available to genotyping of RBC antigens. Expert opinion: It is a platform based on Luminex technology with an automated workflow after DNA extraction and its robustness has been shown through validation studies. This technology provides a useful tool to increase the inventory of antigen-negative RBC units, through a mass-scale donor genotyping for RBC antigens and prevent immunization of patients who require chronic transfusion by providing compatible RBC units based on matching by DNA testing.

Mass-scale red cell genotyping of blood donors: from data visualization to historical antigen labeling and donor recruitment.

Donor red cell genotyping provides efficiencies to identify "in demand" blood donors for transfusion recipients requiring antigen-negative blood. Donor red cell genotype information can be used to label units with historical types and introduced throughout the supply chain from the blood center to the hospital transfusion service and has potential to be used in recruitment strategies.

An update on the Scianna blood group system.

CONCLUSIONS: This update of the Scianna blood group system (Brunker PA, Flegel WA. Scianna: the lucky 13th blood group system. Immunohematology 2011;27:41-57) provides the recent work on the genetic variation of ERMAP across more world populations, the elucidation of the molecular basis of an historical serologic case, new cases of antibodies in the system, the development of new serologic reagents, and new discoveries in the biology of the erythroid membrane associated protein (ERMAP). Although genetic variation in ERMAP has been extensively cataloged, nonsynonymous variants associated with alloantigens have remained limited, and no new antigens have been identified. The first case of a severe hemolytic transfusion reaction to anti-Sc2 has recently been reported, highlighting the importance of pursuing the possibility of antibodies to low-prevalence antigens via indirect antiglobulin testing as a routine component of all transfusion reaction investigations. The expanding use of molecular testing in blood centers and transfusion services has uncovered a wider population distribution of Scianna antigens and heightened the awareness of this blood group system. The International Society of Blood Transfusion recognizes seven antigens in the Scianna blood group system 13.