Showing papers in "Blood Cells Molecules and Diseases in 2023"

Hematologically important mutations: Leukocyte adhesion deficiency (second update).

Abstract: Leukocyte adhesion deficiency (LAD) is an immunodeficiency caused by defects in the adhesion of leukocytes (especially neutrophils) to the blood vessel wall. As a result, patients with LAD suffer from severe bacterial infections and impaired wound healing, accompanied by neutrophilia. In LAD-I, characterized directly after birth by delayed separation of the umbilical cord, mutations are found in ITGB2, the gene that encodes the β subunit (CD18) of the β2 integrins. In the rare LAD-II disease, the fucosylation of selectin ligands is disturbed, caused by mutations in SLC35C1, the gene that encodes a GDP-fucose transporter of the Golgi system. LAD-II patients lack the H and Lewis Lea and Leb blood group antigens. Finally, in LAD-III, the conformational activation of the hematopoietically expressed β integrins is disturbed, leading to leukocyte and platelet dysfunction. This last syndrome is caused by mutations in FERMT3, encoding the kindlin-3 protein in all blood cells, involved in the regulation of β integrin conformation. This article contains an update of the mutations that we consider to be relevant for the various forms of LAD.

High-throughput methods for the analysis of transcription factors and chromatin modifications: Low input, single cell and spatial genomic technologies.

Abstract: Genome-wide analysis of transcription factors and epigenomic features is instrumental to shed light on DNA-templated regulatory processes such as transcription, cellular differentiation or to monitor cellular responses to environmental cues. Two decades of technological developments have led to a rich set of approaches progressively pushing the limits of epigenetic profiling towards single cells. More recently, disruptive technologies using innovative biochemistry came into play. Assays such as CUT&RUN, CUT&Tag and variations thereof show considerable potential to survey multiple TFs or histone modifications in parallel from a single experiment and in native conditions. These are in the path to become the dominant assays for genome-wide analysis of TFs and chromatin modifications in bulk, single-cell, and spatial genomic applications. The principles together with pros and cons are discussed.

Impact of maternal iron deficiency anemia on fetal iron status and placental iron transporters in human pregnancy

Abstract: Iron deficiency anemia is associated with maternal morbidity and poor pregnancy outcomes. Heme and non-heme iron transport proteins expressed in the placenta help in adequate iron supply from anemic mother to fetus. Here we examined the expression of placental iron trafficking molecules and their association with maternal and neonatal iron status in pregnant women with iron deficiency anemia (IDA). Pregnant women who received prenatal care at Christian Medical College, Vellore, India for childbirth were recruited. Pregnant women who were 18-35 years old with gestational age (GA) of ≥36 weeks were eligible to participate in the study. In a prospective cohort of pregnant women, 22 % were iron deficiency anemia and 42 % were iron replete. Samples were collected (Maternal blood, placental tissue, and cord blood) from pregnant women with a gestational age of ≥38 weeks at the time of delivery. The mean gestational age at the first visit and delivery was 12.8 ± 2.72 weeks and 39 ± 1.65 weeks, respectively. Hemoglobin (9.3 ± 0.9 g/dl) and ferritin (15.4(0.8-28.3) ng/ml) levels at delivery were significantly decreased in IDA as compared to controls. The fetal hemoglobin and ferritin levels were in the normal range in both groups. There was no correlation between maternal and cord blood hepcidin with fetal iron status in IDA. We further analyzed the expression of iron transport genes in the placenta of controls and the IDA group. Under maternal iron insufficiency, the expression of placental iron transporters DMT1, FPN1, and GDF15 was upregulated at the protein level. In IDA, placental GDF15 and ferroportin protein had an association with fetal iron status. These findings confirm that placental iron traffickers respond to maternal iron deficiency by increasing their expression and allowing sufficient iron to pass to the fetus.

Essential genetic modifiers and their measurable impact in a community-recruited population analysis for non-severe hemoglobin E/β-thalassemia prenatal genetic counseling

Abstract: The study aimed to identify essential phenotype-modulating factors among the pre-existence of several important ones and clarify their measurable impact on the clinical severity of hemoglobin (Hb) E/β-thalassemia in a community-recruited population analysis. This prospective study was designed to compare modifiers between community- (less or no symptoms) and hospital-recruited individuals with Hb E/β-thalassemia. The formerly included couples previously assessed for prenatal thalassemia at-risk status at 42 community and 7 referral hospitals in Thailand through on-site investigations between June 2020 and December 2021. The control included Hb E/β-thalassemia patients undergoing transfusions. The Mahidol score classified disease severity. Beta-globin, α0-thalassemia (--SEA, --THAI), α+-thalassemia (-α3.7, -α4.2), Hb Constant Spring (αCS) alleles, rs766432 in BCL11A, rs9399137 in HBS1L-MYB, and rs7482144-XmnI were evaluated. Modifiers were compared between 102 community- and 104 hospital-recruited cases. Alleles of β+, --SEA, -α3.7, αCS, and a minor allele of rs9399137 were prevalent in the community and mild severity groups (p < 0.05). Multiple linear regression analysis associated modulating alleles with −4.299 (--SEA), −3.654 (β+), −3.065 (rs9399137, C/C), −2.888 (αCS), −2.623 (−α3.7), −2.361 (rs7482144, A/A), −1.258 (rs9399137, C/T), and −1.174 (rs7482144, A/G) severity score reductions (p < 0.05). Certain modifiers must be considered in routine prenatal genetic counseling for Hb E/β-thalassemia.

Targeting of Calbindin 1 rescues erythropoiesis in a human model of Diamond Blackfan anemia.

Abstract: Diamond Blackfan anemia (DBA) is an inherited bone marrow failure syndrome characterized by congenital anomalies, cancer predisposition and a severe hypo-proliferative anemia. It was the first disease linked to ribosomal dysfunction and >70 % of patients have been identified to have a haploinsufficiency of a ribosomal protein (RP) gene, with RPS19 being the most common mutation. There is significant variability within the disease in terms of phenotype as well as response to therapy suggesting that other genes contribute to the pathophysiology and potential management of this disease. To explore these questions, we performed a genome-wide CRISPR screen in a cellular model of DBA and identified Calbindin 1 (CALB1), a member of the calcium-binding superfamily, as a potential modifier of the disordered erythropoiesis in DBA. We used human derived CD34+ cells cultured in erythroid stimulating media with knockdown of RPS19 as a model for DBA to study the effects of CALB1. We found that knockdown of CALB1 in this DBA model promoted erythroid maturation. We also noted effects of CALB1 knockdown on cell cycle. Taken together, our results reveal CALB1 is a novel regulator of human erythropoiesis and has implications for using CALB1 as a novel therapeutic target in DBA.

Hypoferremia of inflammation: Innate host defense against infections.

Abstract: Iron is an essential nutrient for microbes, plants and animals. Multicellular organisms have evolved multiple strategies to control invading microbes by restricting microbial access to iron. Hypoferremia of inflammation is a rapidly-acting organismal response that prevents the formation of iron species that would be readily accessible to microbes. This review takes an evolutionary perspective to explore the mechanisms and host defense function of hypoferremia of inflammation and its clinical implications.

Characterization of peripheral blood T follicular helper (TFH) cells in patients with type 1 Gaucher disease and carriers.

Abstract: Gaucher disease (GD) is the most common autosomal recessive lipid storage disease. In this study, the changes in TFH cells and IL-4 and IL-21 cytokines in blood samples of GD patients, carriers and healthy volunteers were investigated.Two pretreatment type 1 GD patients, 20 currently treated type 1 GD patients, 6 carriers, and 27 healthy volunteers were enrolled in the study. TFH cell (CD45RA-CD4+CXCR5+) number, phenotype (PD1, ICOS expression), and cytokine production (IL-21, IL-4) were assessed via flow cytometric assays.No significant differences were found between the groups with respect to the number, frequency and PD1 or ICOS expression of TFH cells between healthy controls, patients and carriers. However, IL-4+ TFH cells were significantly reduced both in percent and number in the treated GD patients compared with healthy controls (p < 0.05). Interestingly, the IL-21+ TFH cell number was increased in treated GD patients. When TFH cells were examined based on CXCR3 expression, the frequency of the PD1+Th17-Th2-like fraction (CXCR3-) was found to be significantly increased in treated GD patients.To our knowledge, this is the first study to assess TFH cells in GD patients, and to show that the production of IL-4 and IL-21 by TFH cells and their subsets may be altered in type 1 GD patients.

Cellular and animal models for the investigation of β-thalassemia.

Abstract: β-Thalassemia is a genetic form of anemia due to mutations in the β-globin gene, that leads to ineffective and extramedullary erythropoiesis, abnormal red blood cells and secondary iron-overload. The severity of the disease ranges from mild to lethal anemia based on the residual levels of globins production. Despite being a monogenic disorder, the pathophysiology of β-thalassemia is multifactorial, with different players contributing to the severity of anemia and secondary complications. As a result, the identification of effective therapeutic strategies is complex, and the treatment of patients is still suboptimal. For these reasons, several models have been developed in the last decades to provide experimental tools for the study of the disease, including erythroid cell lines, cultures of primary erythroid cells and transgenic animals. Years of research enabled the optimization of these models and led to decipher the mechanisms responsible for globins deregulation and ineffective erythropoiesis in thalassemia, to unravel the role of iron homeostasis in the disease and to identify and validate novel therapeutic targets and agents. Examples of successful outcomes of these analyses include iron restricting agents, currently tested in the clinics, several gene therapy vectors, one of which was recently approved for the treatment of most severe patients, and a promising gene editing strategy, that has been shown to be effective in a clinical trial. This review provides an overview of the available models, discusses pros and cons, and the key findings obtained from their study.

γ′ fibrinogen levels as a biomarker of COVID-19 respiratory disease severity

Abstract: Coronavirus disease 2019 (COVID-19) is characterized by a pro-inflammatory state associated with organ failure, thrombosis, and death. We investigated a novel inflammatory biomarker, γ′ fibrinogen (GPF), in 103 hospitalized patients with COVID-19 and 19 healthy controls. We found significant associations between GPF levels and the severity of COVID-19 as judged by blood oxygen saturation (SpO2). The mean level of GPF in the patients with COVID-19 was significantly higher than in controls (69.8 (95 % CI 64.8–74.8) mg/dL compared with 36.9 (95 % CI 31.4–42.4) mg/dL, p < 0.0001), whereas C-reactive protein (CRP), lactate dehydrogenase (LDH), and total fibrinogen levels were not significantly different between groups. Mean GPF levels were significantly highest in patients with severe COVID-19 (SpO2 ≤ 93 %, GPF 75.2 (95 % CI 68.7–81.8) mg/dL), compared to mild/moderate COVID-19 (SpO2 > 93 %, GPF 62.5 (95 % CI 55.0–70.0) mg/dL, p = 0.01, AUC of 0.68, 95 % CI 0.57–0.78; Youden's index cutpoint 62.9 mg/dL, sensitivity 0.64, specificity 0.63). In contrast, CRP, interleukin-6, ferritin, LDH, D-dimers, and total fibrinogen had weaker associations with COVID-19 disease severity (all ROC curves with lower AUCs). Thus, GPF may be a useful inflammatory marker of COVID-19 respiratory disease severity.

Mouse models of sickle cell disease: Imperfect and yet very informative.

Abstract: The root cause of sickle cell disease (SCD) has been known for nearly a century, however, few therapies to treat the disease are available. Over several decades of work, with advances in gene editing technology and after several iterations of mice with differing genotype/phenotype relationships, researchers have developed humanized SCD mouse models. However, while a large body of preclinical studies has led to huge gains in basic science knowledge about SCD in mice, this knowledge has not led to the development of effective therapies to treat SCD-related complications in humans, thus leading to frustration with the paucity of translational progress in the SCD field. The use of mouse models to study human diseases is based on the genetic and phenotypic similarities between mouse and humans (face validity). The Berkeley and Townes SCD mice express only human globin chains and no mouse hemoglobin. With this genetic composition, these models present many phenotypic similarities, but also significant discrepancies that should be considered when interpreting preclinical studies results. Reviewing genetic and phenotypic similarities and discrepancies and examining studies that have translated to humans and those that have not, offer a better perspective of construct, face, and predictive validities of humanized SCD mouse models.

Essential genetic modifiers and their measurable impact in a community-recruited population analysis for non-severe hemoglobin E/β-thalassemia prenatal genetic counseling.

Abstract: The study aimed to identify essential phenotype-modulating factors among the pre-existence of several important ones and clarify their measurable impact on the clinical severity of hemoglobin (Hb) E/β-thalassemia in a community-recruited population analysis. This prospective study was designed to compare modifiers between community- (less or no symptoms) and hospital-recruited individuals with Hb E/β-thalassemia. The formerly included couples previously assessed for prenatal thalassemia at-risk status at 42 community and 7 referral hospitals in Thailand through on-site investigations between June 2020 and December 2021. The control included Hb E/β-thalassemia patients undergoing transfusions. The Mahidol score classified disease severity. Beta-globin, α0-thalassemia (-SEA, -THAI), α+-thalassemia (-α3.7, -α4.2), Hb Constant Spring (αCS) alleles, rs766432 in BCL11A, rs9399137 in HBS1L-MYB, and rs7482144-XmnI were evaluated. Modifiers were compared between 102 community- and 104 hospital-recruited cases. Alleles of β+, -SEA, -α3.7, αCS, and a minor allele of rs9399137 were prevalent in the community and mild severity groups (p < 0.05). Multiple linear regression analysis associated modulating alleles with -4.299 (-SEA), -3.654 (β+), -3.065 (rs9399137, C/C), -2.888 (αCS), -2.623 (-α3.7), -2.361 (rs7482144, A/A), -1.258 (rs9399137, C/T), and -1.174 (rs7482144, A/G) severity score reductions (p < 0.05). Certain modifiers must be considered in routine prenatal genetic counseling for Hb E/β-thalassemia.

Molecular characterization of a novel 83.9-kb deletion of the α-globin upstream regulatory elements by long-read sequencing.

Abstract: Inherited deletions of upstream regulatory elements of α-globin genes give rise to α-thalassemia, which is an autosomal recessive monogenic disease. However, conventional thalassemia target diagnosis often fails to identify these rare deletions. Here we reported a family with two previous pregnancies of Hb Bart's hydrops fetalis and was seeking for prenatal diagnosis during the third pregnancy. Both parents had low level of Hemoglobin A2 indicating α-thalassemia. Conventional Gap-PCR and PCR-reverse dot blot showed the father carried -SEA deletion but did not identify any variants in the mother. Multiplex ligation-dependent probe amplification identified a deletion containing two HS-40 probes but could not determine the exact region. Finally, a long-read sequencing (LRS)-based approach directly identified that the exact deletion region was chr16: 48,642-132,584, which was located in the α-globin upstream regulatory elements and named (αα)JM after the Jiangmen city. Gap-PCR and Sanger sequencing confirmed the breakpoint. Both the mother and fetus from the third pregnancy carried heterozygous (αα)JM, and the fetus was normally delivered at gestational age of 39 weeks. This study demonstrated that LRS technology had great advantages over conventional target diagnosis methods for identifying rare thalassemia variants and assisted better carrier screening and prenatal diagnosis of thalassemia.

The utility of multiple genomic technologies for interpretation of modern next generation sequencing: A novel case of three FANCA gene variants resulting in autosomal recessive Fanconi anaemia.

Abstract: Fanconi anaemia (FA) is a rare autosomal recessive condition resulting in changes in the FANC gene family. This report describes a case of Fanconi anaemia in a family with complex biallelic variants. The patient is a 32-year-old female diagnosed with FA on cascade testing during childhood with chromosome breakage studies. On examination she had a fixed deformity of the right thumb and the proximal interphalangeal joint was immobile. Her brother shared this radial abnormality and had FA, requiring a bone marrow transplant. She presented in adulthood seeking further BRCA advice and had next generation sequencing that showed three variants in the FANCA gene. One allele a known pathogenic change, the other had two sequence variants in tandem that have been reported as variants of uncertain significance. There is one other unrelated case of these two variants occurring together in cis, resulting in Fanconi anaemia. This case is an interesting example of three variants in the FANCA gene, one allele with a pathogenic deletion and the other with a single complex allele made up of two missense variants of uncertain significance, likely manifesting with FA. It highlights the utility of different genetic technologies in the interpretation of next generation sequencing.

The inhibitor of MyoD Family A (I-MFA) regulates megakaryocyte lineage commitment and terminal differentiation.

Abstract: Hematopoiesis and lineage commitment are regulated by several conserved cell-intrinsic signaling pathways, including MAPKs and β-catenin/TCF/LEF. The Inhibitor of MyoD Family A (I-MFA), a transcriptional repressor and tumor suppressor gene, interacts with these pathways and is dysregulated in chronic and acute myeloid leukemias, suggesting it may play a role in development and differentiation during hematopoiesis. To study this, immune cell populations in the bone marrow (BM) and periphery were analyzed in mice lacking Mdfi, encoding I-MFA (I-MFA−/−), and wild type (WT) controls. I-MFA−/− mice had reduced spleen and BM cellularity, with significant hyposplenism, compared to WT mice. In blood, total red blood cells and platelet counts were significantly reduced in I-MFA−/− mice, accompanied by a reduction in megakaryocyte (MK)/erythrocyte progenitor cells and an increase in myeloid progenitors in BM compared to WT mice. The K562 cell line exhibits PMA-induced MK differentiation, and shRNA knockdown of I-MFA resulted in reduced differentiation compared to control, with an increase and prolongation in phospho-JNK and phospho-ERK signaling. Overexpression of I-MFA promoted MK differentiation. These results suggest I-MFA plays a cell-intrinsic role in the response to differentiation signals, an effect that can be explored in the context of hematological cancers or other blood proliferative disorders.

Influence of initial clinical suspicion on the diagnostic yield of laboratory enzymatic testing in lysosomal storage disorders. Experience from a multispecialty hospital

Abstract: Lysosomal storage disorders (LSD) are a group of inherited metabolic diseases mainly caused by a deficiency of lysosomal hydrolases, resulting in a gradual accumulation of non-degraded substrates in different tissues causing the characteristic clinical manifestations of such disorders. Confirmatory tests of suspected LSD individuals include enzymatic and genetic testing. A well-oriented clinical suspicion can improve the cost-effectiveness of confirmatory tests and reduce the time expended to achieve the diagnosis. Thus, this work aims to retrospectively study the influence of clinical orientation on the diagnostic yield of enzymatic tests in LSD by retrieving clinical, biochemical, and genetic data obtained from subjects with suspicion of LSD. Our results suggest that the clinical manifestations at the time of diagnosis and the initial clinical suspicion can have a great impact on the diagnostic yield of enzymatic tests, and that clinical orientation performed in specialized clinical departments can contribute to improve it. In addition, the analysis of enzymatic tests as the first step in the diagnostic algorithm can correctly guide subsequent confirmatory genetic tests, in turn increasing their diagnostic yield. In summary, our results suggest that initial clinical suspicion plays a crucial role on the diagnostic yield of confirmatory enzymatic tests in LSD.

Inherited disorders of hemoglobin: A review of old and new diagnostic methods.

Abstract: The genetic regulation of hemoglobin is complex and there are a number of genetic abnormalities that result in clinically important hemoglobin disorders. Here, we review the molecular pathophysiology of hemoglobin disorders and review both old and new methods of diagnosing these disorders. Timely diagnosis of hemoglobinopathies in infants is essential to coordinate optimal life-saving interventions, and accurate identification of carriers of deleterious mutations allows for genetic counseling and informed family planning. The initial laboratory workup of inherited disorders of hemoglobin should include a complete blood count (CBC) and peripheral blood smear, followed by carefully selected tests based on clinical suspicion and available methodology. We discuss the utility and limitations of the various methodologies to fractionate hemoglobin, including cellulose acetate and citrate agar hemoglobin electrophoresis, isoelectric focusing, high-resolution high-performance liquid chromatography, and capillary zone electrophoresis. Recognizing that most of the global burden of hemoglobin disorders exists in low- and middle-income countries, we review the increasingly available array of point-of-care-tests (POCT), which have an increasingly important role in expanding early diagnosis programs to address the global burden of sickle cell disease, including Sickle SCAN, HemoTypeSC, Gazelle Hb Variant, and Smart LifeLC. A comprehensive understanding of the molecular pathophysiology of hemoglobin and the globin genes, as well as a clear understanding of the utility and limitations of currently available diagnostic tests, is essential in reducing global disease burden.

Prevalence of SARS-CoV-2 in hemoglobinopathies is modified by age and race

Abstract: Prior literature has established a positive association between sickle cell disease and risk of contracting SARS-CoV-2. Data from a cross-sectional study evaluating COVID-19 testing devices (n = 10,567) was used to examine the association between underlying health conditions and SARS-CoV-2 infection in an urban metropolis in the southern United States. Firth's logistic regression was used to fit the model predicting SARS-CoV-2 positivity using vaccine status and different medical conditions commonly associated with COVID-19. Another model using the same method was built using SARS-CoV-2 positivity as the outcome and hemoglobinopathy presence, age (<16 Years vs. ≥16 Years), race/ethnicity and comorbidities, including hemoglobinopathy, as the factors. Our first model showed a significant association between hemoglobinopathy and SARS-CoV-2 infection (OR: 2.28, 95 % CI: (1.17,4.35), P = 0.016). However, in the second model, this association was not maintained (OR: 1.35, 95 % CI: (0.72,2.50), P = 0.344). We conclude that the association between SARS-CoV-2 positivity and presence of hemoglobinopathies like sickle cell disease is confounded by race, age, and comorbidity status. Our results illuminate previous findings by identifying underlying clinical/demographic factors that confound the reported association between hemoglobinopathies and SARS-CoV-2. These findings demonstrate how social determinants of health may influence disease manifestations more than genetics alone.

Daratumumab as a novel treatment option in refractory ITP.

Abstract: Primary immune thrombocytopenia (ITP) in adult patients typically presents as a repeatedly relapsing disease in need of multiple lines of therapy. Here we report the clinical courses of two patients, an 82-year-old female and a 54-year-old male, with primary ITP after multiple relapses and exhausted standard therapies, which we treated with the myeloma-licensed anti-CD38 monoclonal antibody daratumumab in an off-label setting. Daratumumab is known to target preferentially plasmablasts, short-lived plasma cells and long-lived plasma cells, with the latter being the major source of antiplatelet autoantibodies. Noteworthy, rituximab, a CD20 antibody, targets earlier steps in B-cell ontogenesis, thereby indirectly decreasing plasmablasts and short-lived plasma cells, but to a lesser extent long-lived plasma cells, which tend to persist after rituximab treatment. Several single-patient reports and case series have demonstrated successful treatment with daratumumab in ITP, autoimmune thrombocytopenia in Evans syndrome as well as other cytopenias or pure red cell aplasia after allogeneic stem cell transplantation or in congenital diseases, systemic lupus erythematodes and cold agglutinin disease. Our first patient with isolated primary ITP rapidly and lastingly responded to daratumumab plus tapered steroids, with platelet counts above 50 × 109/L within weeks and subsequently even stably within the normal range. Despite no objective response observed in the second patient, a lasting clinical stabilization was achieved. As the underlying mode of action, we hypothesize here daratumumab to effectively target long-lived plasma cells as the source of ITP-mediating autoantibodies, and suggest broader clinical evaluation of daratumumab in this potential indication.

Acquired elliptocytosis in chronic myeloid neoplasms: An enigmatic relationship to acquired red cell membrane protein and genetic abnormalities.

Abstract: Nineteen reports of 41 cases of acquired red cell elliptocytosis associated with a chronic myeloid neoplasm are described. Although the majority of cases have an abnormality of the long arm of chromosome 20, del(q20), several cases do not. Moreover, in one case a specific qualitative abnormality of red cell protein band 4.1(4.1R) was reported; however, several subsequent cases could find no abnormality of a red cell membrane protein or found a different abnormality, usually quantitative. Thus, this striking red cell phenotypic feature, acquired elliptocytosis, seen in myelodysplastic syndrome and other chronic myeloproliferative diseases, closely simulating the red cell phenotype of hereditary elliptocytosis, has an unexplained genetic basis, presumably as the result of an acquired mutation(s) in some chronic myeloid neoplasms.

Drinking recommended daily water significantly alters haemato-biochemical parameters in prospective blood donors; a one-center quasi-experimental study in a tropical setting.

Abstract: In sub-Saharan Africa, the prevailing high ambient temperatures should warrant increased daily water intake (DWI) to prevent haemo-concentration and its potential to confound patients' laboratory data. To assess the impact that the recommended DWI has on the haemato-biochemical variables in a tropical setting. This quasi-experimental study recruited 101 apparently healthy individuals (18–60 years) in the Bawku municipality. DWI, anthropometrics, and haemato-biochemical variables were assessed at baseline. Participants were encouraged to increase their DWI to ≥4 L over a 30-day period; haemato-biochemical variables were re-evaluated. Total body water (TBW) was anthropometrically estimated. The median post-treatment DWI significantly increased; consequently, anaemia cases increased by >20-fold (2.0 % vs 47.5 % post-treatment). RBC count, platelet count, WBC count, and median haemoglobin significantly decreased compared to baseline (p < 0.0001). Biochemically, median plasma osmolality (p < 0.0001), serum sodium (p < 0.0001), serum potassium (p = 0.0012) and random blood sugar (p = 0.0403) significantly decreased. Compared to baseline, significantly higher proportion of participants classified as thrombocytopenic (8.9 % vs 3.0 %), hyponatraemia (10.9 % vs 2.0 %), or normal osmolarity (77.2 % vs 20.8 %). There were differential bivariate correlations between pre- and post-treatment haemato-biochemical variables. Sub-optimal DWI is a likely confounder in haemato-biochemical data interpretation in the tropics.

Effects of d-ribose on human erythrocytes: Non-enzymatic glycation of hemoglobin, eryptosis, oxidative stress and energy metabolism.

Abstract: d-Ribose is not only an important component of some biomacromolecules, but also an active pentose with strong reducibility and non-enzymatic glycation ability. Previous studies reported the diverse role of d-ribose in different cells. In this study, the effects of d-ribose on non-enzymatic glycation of hemoglobin (Hb), as well as eryptosis, oxidative stress and energy metabolism of erythrocytes were observed by molecular fluorescence spectrophotometry, multi-wavelength spectrophotometry, high-pressure liquid chromatography (HPLC), mass spectrometry (MS) and flow cytometer. The results showed that d-ribose had the strongest non-enzymatic glycation ability to Hb in vitro when compared with other monosaccharides, and could enter the erythrocytes in a concentration-dependent manner, which was not inhibited by the specific glucose transporter 1 (GLUT1) inhibitor WZB117. In addition, d-ribose incubation increased the HbA1c, hemolysis, eryptosis, and ROS level of erythrocytes significantly more than that of d-glucose, however, no changes were observed in the levels of ATP, NADPH, and other intermediate energy metabolites in d-ribose treatment. Therefore, the strong non-enzymatic glycation ability of d-ribose may play an important role in erythrocyte damage.