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BACKGROUND: the human leukocyte antigen (HLA) loci have been widely characterized to be associated with viral infectious diseases. Several studies including various ethnic groups and populations suggested associations between certain HLA alleles and SARS-CoV-2 infection. Despite the numerous associations identified, the role of HLA polymorphisms in determining the individual response to SARS-CoV-2 infection is controversial among different Saudi populations. METHOD: Here, we performed HLA typing by next-generation sequencing to investigate if variations in polymorphic HLA genes are linked to COVID-19 severity in the Saudi population. Namely, we analyzed HLA loci at allele level in 575 Saudi patients with SARS-CoV-2 infection. HLA class I and class II frequencies in patients were compared with allele frequency data from healthy Saudi population. RESULTS: in our cohort HLA-A* 02:01:01 G was associated with mild disease but was not associated with moderate and severe disease. HLA-B* 51:01:01 G was protective from severe disease while HLA-B* 50:01:01 G, HLA-C* 06:02:01 G and HLA-DRB1 * 07:01:01 G were associated with risk to severe disease as well as the total COVID-19 cohort. HLA-DRB1 * 15:01:01 G was associated with risk to all severity groups. CONCLUSION: in conclusion, we found significant associations between HLA alleles and COVID-19 disease severity in Saudis. Further studies are warranted to include HLA typing in the workup for any new COVID-19 patients.
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Background The associations and risk factors for venous thromboembolism (VTE) among hospitalized COVID-19 patients remain ambiguous in the literature, with some conflicting findings, especially in Saudi Arabia. In this study, we aim to elaborate on these data by examining regional patient populations and exploring the incidence, lab findings, and outcomes of VTE among hospitalized COVID-19 patients known to have diabetes mellitus (DM). Methodology This cross-sectional study was conducted at King Abdulaziz Medical City in Riyadh. The BestCare system was used to collect patients' data between September 2020 and February 2022. JMP15 was used for data analysis. Frequencies and percentages were used for categorical data, and median and interquartile ranges were used for quantitative data. The chi-square and Kruskal-Wallis rank-sum tests were used to assess the difference between categorical and quantitative variables, respectively. Nominal logistical regression was used to assess diabetes as a risk factor for developing VTE among COVID-19 patients. Results Data from 153 admitted patients were collected after they satisfied the inclusion criteria. Of these patients, 39 (25.49%) developed VTE. The demographic data included age group, gender, and DM status presented as frequencies and percentages. Through bivariate analysis, patients with longer hospital stays had at least one episode of VTE (p = 0.0072). Using nominal logistic regression analysis, diabetes as a risk factor (odds ratio = 4.11, confidence interval = 0.955-5.05, p = 0.0287) was significantly associated with the development of VTE in COVID-19 patients. Conclusions Based on our study, diabetes proved significant when evaluating the possible factors regarding VTE development in COVID-19 patients. In addition, the length of stay also played a critical role in the severity of VTE in COVID-19 patients. Similar studies should be conducted on a national scale in Saudi Arabia to accomplish two goals: first, to gain further understanding of the impact of the variables investigated in our population, and second, to publish data that are more generalizable to the larger population of Saudi Arabia.
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The novel HLA-A*02:829 allele is likely generated from the recombination of both HLA-A*02:05:01:01 and HLA-A*32:01:01:01 alleles.
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Alelos , Sequência de Bases , Éxons , Antígeno HLA-A2 , Teste de Histocompatibilidade , Análise de Sequência de DNA , Humanos , Análise de Sequência de DNA/métodos , Antígeno HLA-A2/genética , Antígeno HLA-A2/imunologia , Alinhamento de Sequência , Recombinação Genética , CódonRESUMO
The HLA-B*53:69 allele differs from HLA-B*53:01:01:01 by two nucleotide changes in exon 3.
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Genes MHC Classe I , Antígenos HLA-B , Humanos , Alelos , Antígenos HLA-B/genética , Éxons/genética , Análise de Sequência de DNA , Teste de HistocompatibilidadeRESUMO
BACKGROUND: Human iPSCs' derivation and use in clinical studies are transforming medicine. Yet, there is a high cost and long waiting time associated with autologous iPS-based cellular therapy, and the genetic engineering of hypo-immunogenic iPS cell lines is hampered with numerous hurdles. Therefore, it is increasingly interesting to create cell stocks based on HLA haplotype distribution in a given population. This study aimed to assess the potential of HLA-based iPS banking for the Saudi population. METHODS: In this study, we interrogated the HLA database of the Saudi Stem Cell Donor Registry (SSCDR), containing high-resolution HLA genotype data from 64,315 registered Saudi donors at the time of analysis. This database was considered to be a representative sample of the Saudi population. The most frequent HLA haplotypes in the Saudi population were determined, and an in-house developed iterative algorithm was used to identify their HLA matching percentages in the SSCDR database and cumulative coverage. Subsequently, to develop a clinically relevant protocol for iPSCs generation, and to illustrate the applicability of the concept of HLA-based banking for cell therapy purposes, the first HLA-based iPS cell line in Saudi Arabia was generated. Clinically relevant methods were employed to generate the two iPS clones from a homozygous donor for the most prevalent HLA haplotype in the Saudi population. The generated lines were then assessed for pluripotency markers, and their ability to differentiate into all three germ layers, beating cardiomyocytes, and neural progenitors was examined. Additionally, the genetic stability of the HLA-iPS cell lines was verified by comparing the mutational burden in the clones and the original blood sample, using whole-genome sequencing. The standards set by the American College of Medical Genetics and Genomics (ACMG) were used to determine the clinical significance of identified variants. RESULTS: The analysis revealed that the establishment of only 13 iPSC lines would match 30% of the Saudi population, 39 lines would attain 50% coverage, and 596 lines would be necessary for over 90% coverage. The proof-of-concept HLA-iPSCs, which cover 6.1% of the Saudi population, successfully demonstrated pluripotency and the ability to differentiate into various cell types including beating cardiomyocytes and neuronal progenitors. The comprehensive genetic analysis corroborated that all identified variants in the derived iPSCs were inherently present in the original donor sample and were classified as benign according to the standards set by the ACMG. CONCLUSIONS: Our study sets a road map for introducing iPS-based cell therapy in the Kingdom of Saudi Arabia. It underscores the pragmatic approach of HLA-based iPSC banking which circumvents the limitations of autologous iPS-based cellular therapies. The successful generation and validation of iPSC lines based on the most prevalent HLA haplotype in the Saudi population signify a promising step toward broadening the accessibility and applicability of stem cell therapies and regenerative medicine in Saudi Arabia.
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Células-Tronco Pluripotentes Induzidas , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Arábia Saudita , Medicina Regenerativa , Terapia Baseada em Transplante de Células e Tecidos , HomozigotoRESUMO
Today cord blood (CB) is a valuable source of hematopoietic stem cells to treat many hematological disorders. One of the limitations of CB utilization is the reduced number of nucleated cells including stem cells. Therefore, CB banks around the world have developed strategies in an attempt to improve donor selection and the quality of the CB inventory. This study aimed to determine the impact of passive smoking and caffeine consumption on CB quality. CBs were obtained from mothers who gave birth at King Abdulaziz Medical City. All mothers gave their informed consent. Personal interviews about the mother's demographics, smoking status and exposure, and caffeine consumption executed, followed by a chart review to analyze maternal and neonatal factors. Laboratory testing was performed on all collected CB units. Using descriptive statistics, maternal and newborn factors were analyzed. T-test or Mann-Whitney U Test, as appropriate, for continuous variables analysis to study the effect of second hand smoking and coffee consumption for the primary outcome. Our study demonstrated a reduction in CB MNC, including lymphocytes, in caffeine consumers among pregnant donors, as well as a reduction in cell potency activities, including total CFU and BFU-E. The effect of passive cigarette smoking on the same cohort was insignificant. Outcome of this study will help in optimizing the quality and quantity of stem cell harvesting from CB to get the maximum benefit and such knowledge will raise the awareness among pregnant women.
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Background and objective The coronavirus disease 2019 (COVID-19) pandemic has become a major health concern due to the rapid transmission of the virus that causes it: severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To address the growing demand on healthcare systems to control this pandemic, more effective diagnostic methods need to be applied. In this study, we aimed to compare the efficacy of RealStar® SARS-CoV-2 reverse transcription-polymerase chain reaction (RT-PCR) versus the GeneXpert® system. Methods A retrospective cross-sectional study was conducted in the central lab of King Abdulaziz Medical City (KAMC) in Riyadh, Saudi Arabia. Data from all nasopharyngeal swabs (NPS) (150,000) submitted for SARS-CoV-2 analysis from July 2020 to July 2021 were reviewed retrospectively. Furthermore, all NPS (n=384) that were analyzed on both the RealStar® SARS-CoV-2 RT-PCR and GeneXpert® systems for confirmatory purposes were included in the study. Acute respiratory illness (ARI) screening forms of the selected samples were reviewed from the electronic database (BestCare system), and they were analyzed and compared at one point in time; therefore, a cross-sectional study was found to be the best suitable study design. Using the statistical analysis software, the receiver operating characteristic (ROC) curve was obtained to compare the sensitivity (Sn), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV). The test was considered significant if the area under the curve (AUC) value was >0.5. Results The diagnostic performance of the RealStar® and GeneXpert® assays in detecting SARS-CoV-2 was evaluated using ROC curve analysis, which showed AUCs of 0.597 and 0.637, respectively. In addition, 35% of the total results fell into a substantial agreement of 0.76 (95% CI: 0.6626-0.8732). The majority of the NPS were reported negative by both RealStar® (246, 80.66%) and GeneXpert® (226, 74.10%). Most samples (210, 68.85%) were obtained from asymptomatic patients, scoring less than 4 (ARI <4) based on the ARI screening form. Conclusion Based on the AUC of ROC, there is no significant difference in the performance characteristics between the RealStar® RT-PCR and GeneXpert® in detecting COVID-19.
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Introduction In recent years, there has been a growing trend toward using stem cell transplantation for therapeutic purposes, making a positive impact in the medical field. Access to a compatible and willing donor is essential for those therapeutic purposes, yet the current number of registered donors remains inadequate. The present study aimed to investigate the attitude and perception of stem cell donation among blood donors in Saudi Arabia while also exploring their knowledge of hematopoietic stem cells, willingness towards donation, and fear of complications after stem cell donation. Methods A cross-sectional study was implemented to investigate the perception and attitude toward stem cell donation among blood donors in Riyadh, Saudi Arabia, through a validated self-administered questionnaire. The questionnaire comprised 35 questions divided into five sections, namely, demographics, knowledge, attitude, willingness, and fear of stem cell donation. Results The survey was distributed to 400 subjects. Out of the 400 respondents, 98.8% (n=395) were male, and 90.8% (n=363) were Saudi nationals. The majority had a high school level of education (n=259, 64.75%). Only 10.8% (n=43) of the participants were knowledgeable about stem cells. Knowledge of stem cells was highest among females aged 40-49 years, participants knowledgeable of platelet donation, and participants who donated blood more than 10 times (p-value <0.05). Participants with a bachelor's or master's degree had significantly more fear of stem cell donation complications, with a p-value of 0.003. The attitude toward stem cell donation was highly positive. Most participants strongly agreed to donate stem cells to a family member or anyone in need, 94.5% (n=378) and 62% (n=248), respectively. Conclusion Knowledge about stem cell donation among blood donors was scarce, while their willingness to donate after conversing was high. We highly recommend the initiation and establishment of educational programs to increase the knowledge of the public and, specifically, blood donors.
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Multiple sclerosis (MS) is a disease of the central nervous system (CNS) that is the result of the body's own immune cells being auto-reactive to the myelin regions of the body as if these regions were foreign antigens. This demyelination process is damaging to the electrical conductivity of neurons. The current medicines are only capable of fighting off the symptoms of the disease, but not the disease itself. Specialized stem cells, known as mesenchymal stem cells (MSCs), seem to be the candidate therapy to get rid of MS. MSCs can be isolated from multiple sources of the person's body, and even from the umbilical cord (UC) and placenta of a donor. These cells have anti-inflammatory effects so they can target the overactivity and self-antigen attacks by T cells and macrophages; this immune system overactivity is characteristic of MS. MSCs show the ability to locate into brain lesions when injected and thus can compensate for the loss of the brain function by differentiating into neuronal precursor cells and glial cells. The author has listed tables of clinical trials that have utilized MSCs from different sources, along with the years and the phase of study completed for each trial. The consensus is that these cells work on inhibiting CD4+ and CD8+ T cell activation, T regulatory cells (Tregs), and macrophage switch into the auto-immune phenotype. The best source of MSCs seems to be the UC due to the easiness of extraction, the noninvasive method of collection, their higher expansion ability and more powerful immune-modulating properties compared to other locations in the body. Studies showed there was a significant decline of mRNA expression of several cytokines after the administration of MSCs derived from the UC (UCMSCs). Other researchers were able to repair the defects of Tregs in MS patients by co-culturing Tregs from these patients with UCMSCs, which decreased the production of the pro-inflammatory cytokine IFN γ , and also suggested a strong link between Tregs lack of functionality in MS patients with the pathogenesis of the disease.
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Introduction Innovating strategies have become a compulsion in all fields associated with improved outcomes. Similarly, an innovation was introduced in the curriculum design and content to be tested for the Anatomy and Physiology course at the College of Science and Health Professions (COSHP), King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), in the spring semester of 2020. Before the COVID-19 pandemic, until the spring semester of 2019, two examinations were conducted as continuous assessments (Midterm I and II), followed by a comprehensive Final examination. In the spring semester of 2020, these examinations were replaced with Block I, II, and III examinations, respectively, with modified content and weightage. The Final examination was comprehensive and included 24 Anatomy, 21 Physiology lectures, and three case-based learning (CBL) sessions, whereas Block III included only eight Anatomy, seven Physiology lectures, and 1 CBL session. Midterm I and II weighed 20% each with a comprehensive examination of 35%, while Block I, II, and III were all 25% each. This study focuses on the impact of the curriculum modifications on the results of written examinations for preprofessional students enrolled at Riyadh, Jeddah, and Al-Ahsa campuses. Methods This retrospective study included data from 2356 male and female students from Riyadh, Jeddah, and Al-Ahsa. Data included Midterm I and II grades and Final examination grades for spring semester 2019 and Block I, II, and III examination grades for spring semester 2021. The results of the spring semester 2021 examinations were compared with the spring semester 2019 examination. The spring semester of 2020 was skipped to avoid the effect of online examinations during the COVID-19 restriction period. Data were analyzed using the statistical software SPSS version 23.0 (IBM Corporation, Armonk, NY, USA). Coefficient of variation (CV) compared spring semester 2019 and spring semester 2021 examination outcomes. The findings were analyzed concerning data related to gender, student groups, and campuses. An independent t-test of proportion was used to compare the CVs for spring 2019 and 2021. Results The overall comparison showed better results in the spring semester of 2021 (p-value < 0.01). Campus-wise, the results were significantly better for Riyadh (p-value < 0.01). The gender-wise study showed better performance from male students (p-value < 0.01). Concerning campus and gender, the results of male and female students of the Riyadh campus came out to be highly significant (p-value < 0.01). Conclusions Changing from Midterms to the Block system significantly improved the Block III examination results in spring semester 2021, particularly at the Riyadh campus. Overall, the changes remained helpful to all students. Further studies are needed to investigate the long-term effect of the curriculum changes.
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BACKGROUND: Disease severity among patients infected with SARS-CoV-2 varies remarkably. Preliminary studies reported that the ABO blood group system confers differential viral susceptibility and disease severity caused by SARS-CoV-2. Thus, differences in ABO blood group phenotypes may partly explain the observed heterogeneity in COVID-19 severity patterns, and could help identify individuals at increased risk. Herein, we explored the association between ABO blood group phenotypes and COVID-19 susceptibility and severity in a Saudi Arabian cohort. METHODS: In this retrospective cohort study, we performed ABO typing on a total of 373 Saudi patients infected with SARS-CoV-2 and conducted association analysis between ABO blood group phenotype and COVID-19 infection severity. We then performed gender-stratified analysis by dividing the participating patients into two groups by gender, and classified them according to age. RESULTS: The frequencies of blood group phenotypes A, B, AB and O were 27.3, 23.6, 5.4 and 43.7%, respectively. We found that blood group phenotype O was associated with a lower risk of testing positive for COVID-19 infection (OR 0.76 95% CI 0.62-0.95, p = 0.0113), while blood group phenotype B was associated with higher odds of testing positive (OR 1.51 95% CI 1.17-1.93, p = 0.0009). However, blood group phenotype B was associated with increased risk in the mild and moderate group but not the severe COVID-19 infection group. Blood group phenotype O was protective in all severity groups. CONCLUSION: Our findings provide evidence that blood group phenotype B is a risk for COVID-19 disease while blood group phenotype O is protective from COVID-19 infection. However, further studies are necessary to validate these associations in a larger sample size and among individuals of different ethnic groups.
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Sistema ABO de Grupos Sanguíneos , COVID-19 , Sistema ABO de Grupos Sanguíneos/genética , COVID-19/epidemiologia , Humanos , Fenótipo , Estudos Retrospectivos , SARS-CoV-2 , Arábia Saudita/epidemiologia , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Natural killer (NK) cells play an essential role against viruses. NK cells express killer cell immunoglobulin-like receptors (KIRs) which regulate their activity and function. The polymorphisms in KIR haplotypes confer differential viral susceptibility and disease severity caused by infections. We investigated the association between KIR genes and COVID-19 disease severity. METHODS: 424 COVID-19 positive patients were divided according to their disease severity into mild, moderate and severe. KIR genes were genotyped using next generation sequencing (NGS). Association between KIR genes and COVID-19 disease severity was conducted and significant correlations were reported. RESULTS: In the COVID-19 patients, KIR Bx genotype was more common than AA genotype. The Bx genotype was found more frequently in patients with mild disease, while in severe disease the AA genotype was more common than the Bx genotype. The KIR2DS4 gene carried the highest risk for severe COVID-19 infection (OR 8.48, pc= 0.0084) followed by KIR3DL1 (OR 7.61, pc= 0.0192). CONCLUSIONS: Our findings suggest that KIR2DS4 and KIR3DL1 genes carry risk for severe COVID-19 disease.
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COVID-19/genética , Predisposição Genética para Doença/genética , Polimorfismo Genético/genética , Receptores KIR/genética , Adulto , COVID-19/metabolismo , Feminino , Frequência do Gene/genética , Genótipo , Humanos , Células Matadoras Naturais/metabolismo , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/patogenicidadeRESUMO
Finding HLA-matched donors for patients in need of hematopoietic stem cell transplantation (HSCT) stands a better chance in their own ethnic group. This information led many nations to establish unrelated stem cell donor registries. We started our Saudi Stem Cell Donor registry (SSCDR) in 2011. The calculated donor pool size was nearly 1 million donors to find a matched donor for every patient. So far we have recruited 75,145 donors. In this exercise we attempted to investigate the chances of finding a matched donor for Saudi patients in need of HSCT. A total of 445 patients were recruited for this study. Donor searches were carried out locally and internationally using Prometheus software and World Marrow Donor Association Search and Match Service, respectively. Only 24% of the patients found a matched donor in our registry, 12% found a donor in other registries, making it a total of 36% of our patients who have the chance to find a full 10/10 HLA-matched donor. However, when we included 9/10 and 8/10 with the full matched donors, the chances go up to 83%. The top scoring registries for number of patients finding 10/10 matched donors were SSCDR (108), Deutsche Stammzellspenderdatei Nabelschnurblut (n = 52), King Faisal Specialist Hospital & Research Centre Stem Cell Donor Registry (n = 52), NMDP-National Marrow Donor Program/Be The Match (n = 43), TURKOK-Turkish Stem Cell Coordination Centre (n = 39), DKMS United Kingdom (n = 24), and Ezer Mizion Bone Marrow Donor Registry (n = 20). The patient who found the highest number of donors in international registries carried the European haplotype A1-B8-DR3; a total of 272 donors were found, and none of them were from our registry. Patients with the highest matched donor numbers in SSCDR carried haplotypes that were not common in international registries. Having a local registry increases the chances of finding a matched donor for our patients; however, international registries can still add to the chances of finding matched donors. Increasing our donor pool will increase chances of our patients finding a matched donor.
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Transplante de Células-Tronco Hematopoéticas , Doadores não Relacionados , Teste de Histocompatibilidade , Humanos , Arábia Saudita , Reino UnidoRESUMO
OBJECTIVES: In this study, we evaluated the inflammatory response in patients with severe acute respiratory infection due to the Middle East respiratory syndrome and non-Middle East respiratory syndrome and assessed the presence of distinct inflammatory subphenotypes using latent class analysis. DESIGN: Prospective cohort study. SETTING: A tertiary care ICU in Riyadh, Saudi Arabia. PATIENTS: Consecutive critically ill patients with laboratory-confirmed Middle East respiratory syndrome severe acute respiratory infection and non-Middle East respiratory syndrome severe acute respiratory infection. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: We measured cytokines on days 1, 3, 7, and 14 of ICU stay. We included 116 patients (40 with Middle East respiratory syndrome severe acute respiratory infection and 76 with non-Middle East respiratory syndrome severe acute respiratory infection). On ICU day 1, both patients with Middle East respiratory syndrome severe acute respiratory infection and non-Middle East respiratory syndrome severe acute respiratory infection had higher levels of interleukin-3, interleukin-4, interleukin-6, interleukin-8, interleukin-17A, eotaxin, and epidermal growth factor compared with healthy controls. There were no differences in cytokines over time between patients with Middle East respiratory syndrome severe acute respiratory infection and non-Middle East respiratory syndrome severe acute respiratory infection. Using day 1 cytokine levels, latent class analysis categorized patients into two subphenotypes: subphenotype 1 (n = 74 [64%]) and subphenotype 2 (n = 42 [36%]); the latter had significantly higher levels of interleukin-1ß, interleukin-1ra, interleukin-2, interleukin-6, interleukin-7, interleukin-8, interleukin-10, interleukin-12p70, interleukin-15, interleukin-17A, inducible protein-10, monocyte chemoattractant protein-1, macrophage inflammatory protein-1α, macrophage inflammatory protein-1ß, tumor necrosis factor-α, granulocyte-macrophage colony-stimulating factor, granulocyte-colony stimulating factor, interferon-α, and interferon-γ. Although baseline characteristics were not different between the two subphenotypes, patients in the subphenotype 2 had higher ICU mortality compared with the subphenotype 1 (18/42 [43%] vs 17/74 [23%]; p = 0.03). CONCLUSIONS: One third of critically ill patients with Middle East respiratory syndrome severe acute respiratory infection and non-Middle East respiratory syndrome severe acute respiratory infection demonstrated a subphenotype characterized by increased proinflammatory cytokines, consistent with cytokine storm. Further research is needed to examine whether immunomodulators have differential effects based on inflammatory subphenotypes.
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COVID-19/imunologia , Estado Terminal , Síndrome da Liberação de Citocina/imunologia , Citocinas/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Adulto , COVID-19/complicações , Síndrome da Liberação de Citocina/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Arábia SauditaRESUMO
Human leukocyte antigen (HLA) allele and haplotype frequency distribution varies widely between different ethnicities and geographical areas. Matching for HLA alleles is essential for successful related and unrelated stem cell transplantation. Among the Saudi population, data on HLA alleles and haplotypes are limited. A cross-sectional study was performed on 28,927 bone marrow donors. The most frequent HLA alleles were HLA-A*02:01:01G (20.2%), A*24:02:01G (7.5%); B*51:01:01G (19.0%), B*50:01:01G (12.3%); C*06:02:01G (16.7%), C*07:02:01G (12.2%); DRB1*07:01:01 (15.7%), DRB1*03:01:01G (13.3%); DQB1*02:01:01G (29.9%), DQB1*03:02:01G (13.2%); and DPB1*04:01:01G (35.2%), DPB1*02:01:02G (21.8%). The most frequent HLA-A~C~B~DRB1~DQB1 haplotypes were A*02:01:01G~C*06:02:01G~B*50:01:01G~DRB1*07:01:01G~DQB1*02:01:01G (1.9%) and A*02:05:01G~C*06:02:01G~B*50:01:01G~DRB1*07:01:01G~DQB1*02:01:01G (1.6%). The most frequent HLA-A~C~B~DRB1~DQB1~DPB1 haplotypes were A*02:01:01G~C*15:02:01G~B*51:01:01G~DRB1*04:02~DQB1*03:02:01G~DPB1*04:01:0G (1%) and A*02:01:01G~C*07:02:01G~B*07:02:01G~DRB1*15:01:01G~DQB1*06:02:01G~ DPB1*04:01:01G (0.9%). Based on these haplotype frequencies, we provide forecasts for the fraction of patients with full matching and single mismatched donors for 3 to 6 loci depending on the registry size. With one million donors, about 50% of the patients would find an 8/8 match and 90% a 7/8 match. These data are essential for registry planning, finding unrelated stem cell donors, population genetic studies, and HLA disease associations.
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Frequência do Gene , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Cadeias beta de HLA-DP/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Haplótipos , Células-Tronco , Doadores de Tecidos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Arábia SauditaRESUMO
Acute lymphocytic leukemia is the most common leukemia in children. Many studies suggest the existence of two subsequent hits in order for the disease to occur. TEL-AML1 (ETV6-RUNX1) is considered an initial genetic hit that occurs prenatally and generates a pre-leukemia clone. In cord blood (CB) stem cell transplantation, donor cell leukemia (DCL) is one of the complications associated with the presence of the pre-leukemic clone. The aim of this study was to identify the prevalence of ETV6-RUNX1 translocation in CB units and the feasibility in implementing such a screening test, to ensure the safety of the CB units. A total of 424 CB samples were tested from the CB units banked at KAIMRC-CBB. RNA was extracted and cDNA synthesis was performed on 1 ug input RNA using Reverse Transcriptase RT-PCR methodology. Chromosomal translocation ETV6-RUNX1 was tested using real time quantitative PCR methodology. Our study showed undetectable levels of ETV6-RUNX1 in all tested CB samples. The samples were analyzed for the chromosomal translocation ETV6-RUNX1 under controlled conditions, using control and fusion genes with known concentrations. The result of this study does not rule out the importance of this screening test in predicting and/or preventing DCL. Moreover, the outcome strengthens the adopted system in our CBB for mother medical history screening prior to donation. We propose adding this test during the verification testing stage, prior to the release of CB units selected for transplantation rather than at the banking stage.
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Bancos de Sangue , Cromossomos Humanos/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Sangue Fetal/metabolismo , Programas de Rastreamento , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética , Adulto , Proteínas de Fusão bcr-abl/genética , Humanos , Recém-Nascido , Pessoa de Meia-Idade , Padrões de Referência , Adulto JovemRESUMO
The current COVID-19 pandemic, caused by SARS-CoV-2, has impacted many facets of hematopoietic cell transplantation (HCT) in both developed and developing countries. Realizing the challenges as a result of this pandemic affecting the daily practice of the HCT centers and the recognition of the variability in practice worldwide, the Worldwide Network for Blood and Marrow Transplantation (WBMT) and the Center for International Blood and Marrow Transplant Research's (CIBMTR) Health Services and International Studies Committee have jointly produced an expert opinion statement as a general guide to deal with certain aspects of HCT, including diagnostics for SARS-CoV-2 in HCT recipient, pre- and post-HCT management, donor issues, medical tourism, and facilities management. During these crucial times, which may last for months or years, the HCT community must reorganize to proceed with transplantation activity in those patients who urgently require it, albeit with extreme caution. This shared knowledge may be of value to the HCT community in the absence of high-quality evidence-based medicine. © 2020 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.
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Transplante de Medula Óssea , COVID-19/diagnóstico , COVID-19/terapia , Transplante de Células-Tronco Hematopoéticas , SARS-CoV-2 , COVID-19/epidemiologia , HumanosRESUMO
HLA-DPB1*14:01:11 differs from HLA-DPB1*14:01:01:01 by a single synonymous nucleotide substitution in codon 52.
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Sequenciamento de Nucleotídeos em Larga Escala , Alelos , Sequência de Bases , Cadeias beta de HLA-DP , Humanos , Arábia SauditaRESUMO
HLA-C*06:284 differs from HLA-C*06:02:01:02 by two single nucleotide substitutions in codon 24 (Ser > Thr).
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Antígenos HLA-C , Polimorfismo de Nucleotídeo Único , Alelos , Antígenos HLA-C/genética , Sequenciamento de Nucleotídeos em Larga Escala , Teste de Histocompatibilidade , Humanos , Arábia SauditaRESUMO
HLA-DPB1*10:01:05 differs from HLA-DPB1*10:01:01:01 by a single synonymous nucleotide substitution in exon 2, 38 G>A.