Mature Red Blood Cells Research Articles

Fatty acid desaturase activity in mature red blood cells and implications for blood storage quality.

Increases in the red blood cell (RBC) degree of fatty acid desaturation are reported in response to exercise, aging, or diseases associated with systemic oxidant stress. However, no studies have focused on the presence and activity of fatty acid desaturases (FADS) in the mature RBC. Steady state metabolomics and isotope-labeled tracing experiments, immunofluorescence approaches, and pharmacological interventions were used to determine the degree of fatty acid unsaturation, FADS activity as a function of storage, oxidant stress, and G6PD deficiency in human and mouse RBCs. In 250 blood units from the REDS III RBC Omics recalled donor population, we report a storage-dependent accumulation of free mono-, poly-(PUFAs), and highly unsaturated fatty acids (HUFAs), which occur at a faster rate than saturated fatty acid accumulation. Through a combination of immunofluorescence, pharmacological inhibition, tracing experiments with stable isotope-labeled fatty acids, and oxidant challenge with hydrogen peroxide, we demonstrate the presence and redox-sensitive activity of FADS2, FADS1, and FADS5 in the mature RBC. Increases in PUFAs and HUFAs in human and mouse RBCs correlate negatively with storage hemolysis and positively with posttransfusion recovery. Inhibition of these enzymes decreases accumulation of free PUFAs and HUFAs in stored RBCs, concomitant to increases in pyruvate/lactate ratios. Alterations of this ratio in G6PD deficient patients or units supplemented with pyruvate-rich rejuvenation solutions corresponded to decreased PUFA and HUFA accumulation. Fatty acid desaturases are present and active in mature RBCs. Their activity is sensitive to oxidant stress, storage duration, and alterations of the pyruvate/lactate ratio.

Potential of Erythrocyte Membrane Lipid Profile as a Novel Inflammatory Biomarker to Distinguish Metabolically Healthy Obesity in Children.

Metabolically healthy obesity (MHO) has been described as BMI ≥ 30 kg/m2, without metabolic disorders traditionally associated with obesity. Beyond this definition, a standardized criterion, for adults and children, has not been established yet to explain the absence of those metabolic disorders. In this context, biomarkers of inflammation have been proposed as suitable candidates to describe MHO. The use of mature red blood cell fatty acid (RBC FA) profile is here proposed since its membrane lipidome includes biomarkers of pro- and anti-inflammatory conditions with a strict relationship with metabolic and nutritional status. An observational study was carried out in 194 children (76 children with obesity and 118 children with normal weight) between 6 and 16 years old. RBC FAs were analyzed by gas chromatography-flame ionization detector (GC-FID). An unsupervised hierarchical clustering method was conducted on children with obesity, based on the RBC FA profile, to isolate the MHO cluster. The MHO cluster showed FA levels similar to children with normal weight, characterized by lower values of arachidonic acid, (total ω-6 FA, ω6/ω3 FA ratios and higher values for EPA, DHA, and total ω-3 FA) (for all of them p ≤ 0.01) compared to the rest of the children with obesity (obese cluster). The MHO cluster also presented lipid indexes for higher desaturase enzymatic activity and lower SFA/MUFA ratio compared to the obese cluster. These differences are relevant for the follow-up of patients, also in view of personalized protocols providing tailored nutritional recommendations for the essential fatty acid intakes.

Deficient mitophagy pathways in sickle cell disease

Sickle cell disease (SCD) is characterised by chronic haemolysis and oxidative stress. Herein, we investigated 30 SCD patients and found 40% with elevated mitochondria levels (SS-mito+ ) in their mature red blood cells, while 60% exhibit similar mitochondria levels compared to the AA group (SS-mito- ). The SS-mito+ patients are characterised by higher reticulocytosis and total bilirubin levels, lower foetal haemoglobin, and non-functional mitochondria. Interestingly, we demonstrated decreased levels of mitophagy inducers, PINK1 and NIX, and higher levels of HSP90 chaperone in their red cells. Our results highlighted for the first time an abnormal retention of mitochondria in SCD linked with mitophagy-related proteins.

A novel compound heterozygous mutation of MYSM1 gene in a patient with bone marrow failure syndrome 4

Myb-like swirm and MPN domains 1 (MYSM1) is a gene encoding histone H2A deubiquitinase, which can regulate the expression of transcription factor related genes and involve the immune and hematopoietic system. Homozygous and missense mutations of MYSM1 lead to immune deficiency, mainly manifested by B cell deficiency and T cell reduction. Bone marrow failure syndrome 4 (BMFS 4) is an autosomal recessive disorder characterized by early-onset anemia, leukopenia, and decreased B cells, resulting in an increased susceptibility to infection. Here, we report a 2-month-old girl with a highly suspected BMFS due to the clinical characteristics of recurrent, severe anemia, intermittent thrombocytopenia, polydactylism, and slow growth. Whole exome sequencing identified a compound heterozygous mutation with c.1607_c.1611delAAGAG (exon 12) from the mother and c.1432C>T (exon 10) from the father in the girl. We suggest that c.1607_c.1611delAAGAG is a newly discovered pathogenic mutation. In addition, the mutation c.1432C>T (exon 10), rs748065332 is a truncated mutation (p.R478*,351), which is also reported for the first time. This case expands the phenotypic spectrum of BMSF4 and is helpful to explore the significance of BMFS4 gene detection in children with bone marrow failure syndrome.

Cloning and expression analysis of GATA1 gene in Carassius auratus red var

BackgroundGATA1 is a key transcription factor in the GATA family, and promotes the differentiation and maturation of red blood cell, which is essential for normal hematopoiesis.ResultsOur results showed that the cDNA sequence of GATA1 was 2730 bp long encoding 443 amino acids. qRT-PCR analysis demonstrated that GATA1 had the highest expression in testis (T), followed by pituitary (P) and spleen (S). GATA1 gene expression in C. auratus red var. embryo from the neuroblast stage (N) to the embryo hatching (H) changes continuously; and the gene expression levels of nonylphenol (NP)-treated and those of control embryos were significantly different. Moreover, Methylation levels of GATA1 gene in NP-treated embryos were higher than those in control embryos, indicating that NP affected GATA1 methylation.ConclusionsOur study provides cues for further studying the roles of GATA1 gene in fish development, and suggested a potential molecular mechanism by which NP leads to abnormal development of fish embryos.

Appearance of hypersegmented neutrophils in the peripheral blood associated with subacute combined degeneration of the spinal cord due to nitrous oxide abuse

A 25-year-old man following 1 year of recreational nitrous oxide (N2O) use presented with quadriplegia and decreased sensation in a glove and stocking distribution. The weakness distally was 2/5 and proximally 2–3/5. The spinal cord lesions showed an increased signal in a V-shape within the posterior column on T2-weighted magnetic resonance imaging (MRI) extending posteriorly from the C1–C2 level to the C5 level. Laboratory tests showed: white cell count 4.39 × 109/l, red cell count 3.95 × 109/l, haemoglobin concentration 133 g/l, haematocrit 0.39 l/l, mean corpuscular volume 99.4 fl (normal range 82–100), mean corpuscular haemoglobin 33.8 pg, mean corpuscular haemoglobin concentration 340 g/l, red cell distribution width 16.2% (9.0–17.0), platelet count 175 × 109/l, serum folate 22.82 ng/ml (5.90–24.80), homocysteine 11.3 μmol/l (0.0–20.0), methylmalonic acid 296 nmol/l (73–376), vitamin B12 312 pg/ml (180–914) and thiamine 165.3 nmol/l (66.5–200). The differential white cell count was normal but a peripheral blood film showed hypersegmented neutrophils, 19% having 6 lobes (normal 1–5) (images, ×100 objective, Wright–Giemsa stain). Neutrophil alkaline phosphatase was normal. The morphology of mature red blood cells showed no obvious abnormality. The patient received intensive physiotherapy and vitamin B12 therapy. At outpatient review 6 weeks later, his symptoms had improved considerably. Neurological examination was normal apart from a mild hyporeflexia of the lower limbs. His peripheral blood film no longer showed neutrophil hypersegmentation. The clinical diagnosis of nitrous oxide abuse causing subacute combined degeneration of the spinal cord mainly depends on a history of N2O inhalation. However patients who are generally young men may conceal the N2O abuse history. Hence, clinical staff should be aware not only of the various presentations of neurotoxicity, but also the peripheral blood features related to N2O abuse.

Donor Age and Red Cell Age Contribute to the Variance in Lorrca Indices in Healthy Donors for Next Generation Ektacytometry: A Pilot Study

The ability of red blood cells (RBCs) to transport gases, their lifespan as well as their rheological properties invariably depend on the deformability, hydration, and membrane stability of these cells, which can be measured by Laser optical rotational red cell analyser (Lorrca® Maxsis, RR Mechatronics). The osmoscan mode of Lorrca is currently used in diagnosis of rare anemias in clinical laboratories. However, a broad range of normal values for healthy subjects reduces the sensitivity of this method for diagnosis of mild disease phenotype. In this pilot study, we explored the impact of age and gender of 45 healthy donors, as well as RBC age on the Lorrca indices. Whereas gender did not affect the Lorrca indices in our study, the age donors had a profound effect on the O_hyper parameter. To study the impact of RBC age on the osmoscan parameters, we have isolated low (L)-, medium (M)-, or high (H)- density fractions enriched with young, mature, and senescent RBCs, respectively, and evaluated the influence of RBC age-related properties, such as density, morphology, and redox state, on the osmoscan indices. As before, O_hyper was the most sensitive parameter, dropping markedly with an increase in RBC density and age. Senescence was associated with a decrease in deformability (EI_max) and tolerability to low and high osmolatites (Area). L-fraction was enriched with reticulocytes and cells with high projected area and EMA staining, but also contained a small number of cells small in projected area and most likely, terminally senescent. L-fraction was on average slightly less deformable than mature cells. The cells from the L-fraction produced more oxidants and NO than all other fractions. However, RBCs from the L-fraction contained maximal levels of reduced thiols compared to other fractions. Our study suggests that reference values for O_hyper should be age-stratified, and, most probably, corrected for the average RBC age. Further multi-center study is required to validate these suggestions before implementing them into clinical practice.

Novel mechanism of hereditary pyropoikilocytosis phenotype due to co‐inheritance of β globin and α spectrin mutations

Novel mechanism of hereditary pyropoikilocytosis phenotype due to co‐inheritance of β globin and α spectrin mutations

Erythrocytes 3D genome organization in vertebrates

Generation of mature red blood cells, consisting mainly of hemoglobin, is a remarkable example of coordinated action of various signaling networks. Chromatin condensation is an essential step for terminal erythroid differentiation and subsequent nuclear expulsion in mammals. Here, we profiled 3D genome organization in the blood cells from ten species belonging to different vertebrate classes. Our analysis of contact maps revealed a striking absence of such 3D interaction patterns as loops or TADs in blood cells of all analyzed representatives. We also detect large-scale chromatin rearrangements in blood cells from mammals, birds, reptiles and amphibians: their contact maps display strong second diagonal pattern, representing an increased frequency of long-range contacts, unrelated to TADs or compartments. This pattern is completely atypical for interphase chromosome structure. We confirm that these principles of genome organization are conservative in vertebrate erythroid cells.

Impaired Cytoskeletal and Membrane Biophysical Properties of Acanthocytes in Hypobetalipoproteinemia - A Case Study.

Familial hypobetalipoproteinemia is a metabolic disorder mainly caused by mutations in the apolipoprotein B gene. In its homozygous form it can lead without treatment to severe ophthalmological and neurological manifestations. In contrast, the heterozygous form is generally asymptomatic but associated with a low risk of cardiovascular disease. Acanthocytes or thorny red blood cells (RBCs) are described for both forms of the disease. However, those morphological changes are poorly characterized and their potential consequences for RBC functionality are not understood. Thus, in the present study, we asked whether, to what extent and how acanthocytes from a patient with heterozygous familial hypobetalipoproteinemia could exhibit altered RBC functionality. Acanthocytes represented 50% of the total RBC population and contained mitoTracker-positive surface patches, indicating the presence of mitochondrial fragments. While RBC osmotic fragility, calcium content and ATP homeostasis were preserved, a slight decrease of RBC deformability combined with an increase of intracellular free reactive oxygen species were observed. The spectrin cytoskeleton was altered, showing a lower density and an enrichment in patches. At the membrane level, no obvious modification of the RBC membrane fatty acids nor of the cholesterol content were detected but the ceramide species were all increased. Membrane stiffness and curvature were also increased whereas transversal asymmetry was preserved. In contrast, lateral asymmetry was highly impaired showing: (i) increased abundance and decreased functionality of sphingomyelin-enriched domains; (ii) cholesterol enrichment in spicules; and (iii) ceramide enrichment in patches. We propose that oxidative stress induces cytoskeletal alterations, leading to increased membrane stiffness and curvature and impaired lipid lateral distribution in domains and spicules. In addition, ceramide- and spectrin-enriched patches could result from a RBC maturation defect. Altogether, the data indicate that acanthocytes are associated with cytoskeletal and membrane lipid lateral asymmetry alterations, while deformability is only mildly impaired. In addition, familial hypobetalipoproteinemia might also affect RBC precursors leading to disturbed RBC maturation. This study paves the way for the potential use of membrane biophysics and lipid vital imaging as new methods for diagnosis of RBC disorders.

20S proteasomes secreted by the malaria parasite promote its growth

Mature red blood cells (RBCs) lack internal organelles and canonical defense mechanisms, making them both a fascinating host cell, in general, and an intriguing choice for the deadly malaria parasite Plasmodium falciparum (Pf), in particular. Pf, while growing inside its natural host, the human RBC, secretes multipurpose extracellular vesicles (EVs), yet their influence on this essential host cell remains unknown. Here we demonstrate that Pf parasites, cultured in fresh human donor blood, secrete within such EVs assembled and functional 20S proteasome complexes (EV-20S). The EV-20S proteasomes modulate the mechanical properties of naïve human RBCs by remodeling their cytoskeletal network. Furthermore, we identify four degradation targets of the secreted 20S proteasome, the phosphorylated cytoskeletal proteins β-adducin, ankyrin-1, dematin and Epb4.1. Overall, our findings reveal a previously unknown 20S proteasome secretion mechanism employed by the human malaria parasite, which primes RBCs for parasite invasion by altering membrane stiffness, to facilitate malaria parasite growth.

The Redox Balance and Membrane Shedding in RBC Production, Maturation, and Senescence.

Membrane shedding in the form of extracellular vesicles plays a key role in normal physiology and pathology. Partial disturbance of the membrane–cytoskeleton linkage and increased in the intracellular Ca content are considered to be mechanisms underlying the process, but it is questionable whether they constitute the primary initiating steps. Homeostasis of the redox system, which depends on the equilibrium between oxidants and antioxidants, is crucial for many cellular processes. Excess oxidative power results in oxidative stress, which affects many cellular components, including the membrane. Accumulating evidence suggests that oxidative stress indirectly affects membrane shedding most probably by affecting the membrane–cytoskeleton and the Ca content. In red blood cells (RBCs), changes in both the redox system and membrane shedding occur throughout their life—from birth—their production in the bone marrow, to death—aging in the peripheral blood and removal by macrophages in sites of the reticuloendothelial system. Both oxidative stress and membrane shedding are disturbed in diseases affecting the RBC, such as the hereditary and acquired hemolytic anemias (i.e., thalassemia, sickle cell anemia, and autoimmune hemolytic anemia). Herein, I review some data-based and hypothetical possibilities that await experimental confirmation regarding some aspects of the interaction between the redox system and membrane shedding and its role in the normal physiology and pathology of RBCs.

Red cell manufacturing using parallel stirred-tank bioreactors at the final stages of differentiation enhances reticulocyte maturation.

The aim of this study was to develop a robust, quality controlled, and reproducible erythroid culture system to obtain high numbers of mature erythroblasts and red blood cells (RBCs). This was achieved using a fully controlled stirred-tank bioreactor by the design of experiments (DOE) methods in the serum-free medium by defining the appropriate culture parameters. Human cord blood CD34+ cells were first cultured in static flasks and then inoculated to stirred-tank bioreactors. Cell diameter was gradually decreased and final RBC yields were significantly higher when cells were inoculated at sizes smaller than 12 μm. The larger immature cells in the basophilic stage did not survive, while smaller mature erythroid cells were successfully expanded at high agitation speeds, demonstrating that appropriate seeding timing is critical. A high inoculation cell density of 5 × 106 cells/ml was achieved reaching 1.5 × 107 cells/ml. By using DOE analysis fitted to precise stages of erythropoiesis, we were able to acquire the optimal culture parameters for pH (7.5), temperature (37°C), dissolved oxygen, agitation speed (500 rpm), inoculation timing (cell diameter 12-13 μm), media feeding regimen, and cell seeding density (5 × 106 cells/ml). The final pure RBCs showed appropriate functions compared with fresh donor RBCs, confirming that manufacturing mature RBCs with reproducibility is possible.

Requirement for antiapoptotic MCL-1 during early erythropoiesis

Although BCL-xL is critical to the survival of mature erythrocytes, it is still unclear whether other antiapoptotic molecules mediate survival during earlier stages of erythropoiesis. Here, we demonstrate that erythroid-specific Mcl1 deletion results in embryonic lethality beyond embryonic day 13.5 as a result of severe anemia caused by a lack of mature red blood cells (RBCs). Mcl1-deleted embryos exhibit stunted growth, ischemic necrosis, and decreased RBCs in the blood. Furthermore, we demonstrate that MCL-1 is only required during early definitive erythropoiesis; during later stages, developing erythrocytes become MCL-1 independent and upregulate the expression of BCL-xL. Functionally, MCL-1 relies upon its ability to prevent apoptosis to promote erythroid development because codeletion of the proapoptotic effectors Bax and Bak can overcome the requirement for MCL-1 expression. Furthermore, ectopic expression of human BCL2 in erythroid progenitors can compensate for Mcl1 deletion, indicating redundancy between these 2 antiapoptotic family members. These data clearly demonstrate a requirement for MCL-1 in promoting survival of early erythroid progenitors.

Molecular Differences Based on Erythrocyte Fatty Acid Profile to Personalize Dietary Strategies between Adults and Children with Obesity.

As the obesity epidemic continues to grow inexorably worldwide, the need to develop effective strategies to prevent and control obesity seems crucial. The use of molecular tools can be useful to characterize different obesity phenotypes to provide more precise nutritional recommendations. This study aimed to determine the fatty acid (FA) profile of red blood cell (RBC) membranes, together with the evaluation of their dietary intake and biochemical parameters, of children and adults with obesity. An observational study was carried out on 196 children (113 with normal weight and 83 with obesity) and 91 adults (30 with normal weight and 61 with obesity). Mature RBC membrane phospholipids were analyzed for FA composition by gas chromatography-mass spectrometry (GC-MS). Dietary habits were evaluated using validated food frequency questionnaires (FFQ). Children with obesity presented higher levels of ω-6 polyunsaturated FAs (mainly linoleic acid, p = 0.01) and lower values of ω-3 FAs (mainly DHA, p < 0.001) compared with adults. Regarding blood biochemical parameters, children with obesity presented lower levels of glucose, LDL cholesterol, and alanine aminotransferase compared with adults with obesity. These lipidomic differences could be considered to provide specific nutritional recommendations for different age groups, based on an adequate fat intake.

Rare anemias in adolescents.

Anemia can be the consequence of a single disease or an expression of external factors mainly nutritional deficiencies. Genetic issues are important in the primary care of adolescents because a genetic diagnosis may not be made until adolescence, when the teenager presents with the first signs or symptoms of the condition. This situation is relatively frequent for rare anemias (RA) an important, and relatively heterogeneous group of rare diseases (RD) where anaemia is the first and most relevant clinical manifestation. RA are characterised by their low prevalence (< 5 cases per 10,000 individuals), and, in some cases, by their complex mechanism. For these reasons, RA are little known, even among health professionals, and patients tend to remain undiagnosed or misdiagnosed for long periods of time, making impossible to know the prognosis of the disease, or to carry out genetic counselling for future pregnancies. Since this situation is an important cause of anxiety for both adolescent patients and their families, the physician’s knowledge of the natural history of a genetic disease will be the key factor for the anticipatory guidance for diagnosis and clinical follow-up. RA can be due to three primary causes: 1. Bone marrow erythropoietic defects, 2. Excessive destruction of mature red blood cells (hemolysis), and 3. Blood loss (bleeding). More than 80% of RAs are hereditary, and about 20% remain undiagnosed but when their first clinical manifestations appear during childhood or adolescence, they are frequently misdiagnosed with iron deficiency. For this reason, RA are, today, an important clinical and social health challenge worldwide. (www.actabiomedica.it)

Differential diagnosis of thalassemia and iron deficiency anemia in pregnant women using new formulas from multidimensional analysis of red blood cells.

BackgroundIron deficiency anemia (IDA) and thalassemia trait (TT) are the most common conditions of microcytic hypochromic anemia (MHA) in pregnant women. We used the BC-6800Plus analyzer to study the utility of erythrocyte and reticulocyte parameters for distinguishing TT from IDA in pregnant women.MethodsA total of 454 anemic pregnant women, including 340 with IDA, 66 with β-thalassemia trait (β-TT) and 48 with α-thalassemia trait (α-TT), were included. Multiple comparisons among groups were performed, and diagnostic performance of parameters was determined using receiver operating characteristic (ROC) curve analysis, with P<0.05 indicating statistical significance.ResultsReticulocyte production index (RPI) and the average volume of mature red blood cells (MCVm) in the IDA group were significantly higher than in the β-TT and α-TT groups. Red blood cell (RBC), reticulocyte percentage (Ret%), and RPI in the IDA group were significantly lower than in the α-TT and β-TT groups. We devised MHA 1=0.42× MCH −0.57× RPI −0.08× %MICROr −9.38 to distinguish IDA from α-TT. With a cut-off value of 0.61, the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were 0.868, 90.9%, and 68.5%, respectively. We devised MHA 2=0.04× %MICROr +0.12× MCVm −13.76× Ret# −6.29 to distinguish IDA from β-TT. With a cut-off value of 0.55, the AUC, sensitivity, and specificity were 0.878, 81.3%, and 80.3%, respectively.ConclusionsErythrocyte indices and formulas can be used as initial methods for the differential diagnosis of TT and IDA. MHA 1 and MHA 2 were the most useful indices in the differential diagnosis of α-TT from IDA and β-TT from IDA in pregnant women.

Persistence and periodicity of survival red blood cells model with time-varying delays and impulses

<abstract> In this paper, a class of survival red blood cells model with time-varying delays and impulsive effects is considered. First, some sufficient conditions for the persistence are derived by use of the theory on impulsive differential equations. The persistence describes the persistent survival of the mature red blood cells in the mammal under delay and impulsive perturbations. Then assuming that the coefficients in the model are $ \omega $-periodic, some criteria ensuring the existence-uniqueness and global attractivity of positive $ \omega $-periodic solution of the addressed model are obtained, which are suitable for survival red blood cells model with any $ \omega\in \mathbb{R}_+ $. These global attractivity criteria describe the nonexistence of any dynamic diseases in the mammal. Moreover, our proposed results in this paper extend and improve some recent works in the literature. Finally, two examples and their computer simulations are given to show the effectiveness and advantages of the results. </abstract>

Expansion of immature, nucleated red blood cells by transient low-dose methotrexate immune tolerance induction in mice.

Biological treatments such as enzyme-replacement therapies (ERT) can generate anti-drug antibodies (ADA), which may reduce drug efficacy and impact patient safety and consequently led to research to mitigate ADA responses. Transient low-dose methotrexate (TLD-MTX) as a prophylactic ITI regimen, when administered concurrently with ERT, induces long-lived reduction of ADA to recombinant human alglucosidase alfa (rhGAA) in mice. In current clinical practice, a prophylactic ITI protocol that includes TLD-MTX, rituximab and intravenous immunoglobulin (optional), successfully induced lasting control of ADA to rhGAA in high-risk, cross-reactive immunological material (CRIM)-negative infantile-onset Pompe disease (IOPD) patients. More recently, evaluation of TLD-MTX demonstrated benefit in CRIM-positive IOPD patients. To more clearly understand the mechanism for the effectiveness of TLD-MTX, non-targeted transcriptional and proteomic screens were conducted and revealed up-regulation of erythropoiesis signatures. Confirmatory studies showed transiently larger spleens by weight, increased spleen cellularity and that following an initial reduction of mature red blood cells (RBCs) in the bone marrow and blood, a significant expansion of Ter-119+ CD71+ immature RBCs was observed in spleen and blood of mice. Histology sections revealed increased nucleated cells, including hematopoietic precursors, in the splenic red pulp of these mice. This study demonstrated that TLD-MTX induced a transient reduction of mature RBCs in the blood and immature RBCs in the bone marrow followed by significant enrichment of immature, nucleated RBCs in the spleen and blood during the time of immune tolerance induction, which suggested modulation of erythropoiesis may be associated with the induction of immune tolerance to rhGAA.

Erythrocyte and reticulocyte parameters during biological monitoring of lead exposure to the body

Introduction. The most susceptible to lead is the hematopoietic system of hematopoietic organs due to lead inhibition of heme and globin synthesis and cytotoxic effect on the membrane of Mature red blood cells. The aim of study was to evaluate the informative value of the study of erythrocyte and reticulocyte parameters determined on modern hematological analyzers in patients working in contact with lead during medical and biological monitoring. Materials and methods. 45 employees of the lead battery processing plant and 30 persons of control group were examined. The level of lead in the blood was determined by atomic absorption spectrometry, δ-ALA in the urine-by the reaction of pyrol formation with acetylacetone in terms of gram of creatinine, the study of hematological parameters was performed on a Sysmex HT-2000i analyzer. Statistical processing of the results was performed using the program STATISTICA 10.0. Results. Significant changes in erythrocytic (RDW) and reticulocytic (RET, IRF, LFR, MFR, HFR, RET-He) parameters, erythropoietin in workers in contact with lead compared to the control group, changes in MCV, MCH, RDW, RET indicators in the group working in dynamics after 2 years were revealed. Associations of hematological parameters with biomarkers of exposure and effect (lead level in blood and ALA in urine) were revealed. Conclusions. Assessment of erythrocyte (MCV, MCH, RDW) and reticulocyte parameters (RET% and their distribution by maturity) in dynamics during periodic medical examinations of workers in contact with lead allows us to detect the development of hematological disorders at early stages.