Red Cell Shape Research Articles

Biomimetic Approach for Optimal Designing of the Shape and Controlled Release of Therapeutics from Tricompartmental Microcarriers for Managing Parkinson's Disease.

Inspired by the intricate cellular morphology and the discoid shape of red blood cells (RBCs), biomimetic tricompartmental microcarriers (TCM) with controlled release profiles were engineered using an electrohydrodynamic-co-jetting technique for efficient management of Parkinson's disease (PD). While jetting, Levodopa (LD), CD (Carbidopa), and ENT (Entacapone) (3 PD drugs) were directly encapsulated in the three individual compartments of the TCM used for oral administration. The optimal shape and controlled release profiles were obtained by employing the Taguchi orthogonal L9 design-of-experiment approach by systematically varying the processing parameters, i.e., solvent ratio, polymer concentration, and flow rate. The "smaller-the-better" norm for the S/N ratio demonstrated the solvent ratio (DMF content) and polymer concentration as the most influential parameters in ensuring the RBC shape and controlling the release of drugs. Analysis of variance and response surface methodology approach provided insights into the optimal influence of control factors on the response variables. Confirmation experiments further validated the optimized microparticles (Poptimized), demonstrating an error of only ∼0.13% in aspect ratio deviation (ARDEV) and ∼19% (within the tolerance limit) in release factor (RF) from the predicted experiment. Moreover, Poptimized exhibits ∼100% encapsulation efficiency of all three PD drugs, with the cumulative release of ∼100% LD, ∼97% CD, and ∼65% ENT within 5 h of the in vitro study. In addition, in vivo studies such as pharmacokinetics (using healthy rats) and pharmacodynamics [using the MPTP (methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-injected PD-induced mice model] showed that the TCM can effectively control the release of LD (primary drug) for a prolonged period, thereby promising sustained drug delivery and improved therapeutics outcomes.

Predicting natural and unnatural red blood cell shape transformations

The nonlinear model accurately predicts the stomatocyte-discocyte-echinocyte transformation in red blood cells.

Minimally invasive treatment with radiofrequency ablation and kyphoplasty for avascular necrosis of the spine in sickle cell disease: illustrative case.

Avascular necrosis (AVN) of the spine is a rare sequela of chronic sickle cell disease (SCD) in which the shape of the sickled red blood cells interfere with the normal vascular supply of vertebral bodies. In this report, the authors describe a case of progressive spinal AVN treated with radiofrequency ablation (RFA) and kyphoplasty for the patient's persistent lower back pain. A 38-year-old male with long-standing spinal AVN due to SCD had been managed conservatively with hydroxyurea and oral opioid analgesics for several years until breakthrough episodes of low-back pain began to occur with an inability to perform activities of daily life. The patient's condition progressed to involve multiple vertebral bodies, leading to a refractory response. Bipedicular RFA directed at L3 and L4 with kyphoplasty was proposed as a novel, minimally invasive approach. The patient was found to have lasting postoperative relief. Patients with pain attributed to a sickle cell crisis can benefit from RFA and kyphoplasty to potentially eliminate or minimize symptoms from spinal AVN due to chronic SCD not responding to conservative management. https://thejns.org/doi/10.3171/CASE24343.

The Effect of the Acid-Base Imbalance on the Shape and Structure of Red Blood Cells.

Red blood cells respond to fluctuations in blood plasma pH by changing the rate of biochemical and physical processes that affect the specific functions of individual cells. This study aimed to analyze the effect of pH changes on red blood cell morphology and structure. The findings revealed that an increase or decrease in pH above or below the physiological level of pH 7.4 results in the transformation of discocytes into echinocytes and causes significant alterations in the membrane, including its roughness, cytoskeleton structure, and the cell's elastic modulus. Furthermore, the study shown a strong connection between critical acidosis and alkalosis with increased intracellular reactive oxygen species production.

Deposit of Red Blood Cells at low concentrations in evaporating droplets is dominated by a central edge growth

Evaporation of blood droplets and diluted blood samples is a topic of intensive research, as it is considered a potential low-cost diagnostic tool. So far, samples with a volume fraction down to a few percent of red blood cells have been studied, and these were reportedly dominated by a “coffee-ring” deposit. In this study, samples with lower volume fractions were used to investigate the growth of the evaporative deposit from sessile droplets in more detail. We observed that blood samples and salt solutions with less than 1% volume fraction of red blood cells are dominated by a central deposit. We characterized the growth process of this central deposit by evaporating elongated drops and determined that it is consistent with the Kardar-Parisi-Zhang process in the presence of quenched disorder. Our results showed a sensitivity of the deposit size to fibrinogen concentration and the shape of red blood cells, suggesting that this parameter could be developed into a new and cost-effective clinical marker for inflammation and red blood cell deformation.

Neurovascular Manifestations of Sickle Cell Disease

Sickle cell disease (SCD) is a hereditary blood disorder characterized by abnormal hemoglobin, leading to the sickle shape of red blood cells. It has several vascular complications and the cerebrovascular ones are among the most frequent and severe both in children and in adults. This review summarizes the main neurovascular manifestations of SCD, including acute stroke, silent cerebral infarction, large-vessel diseases (moyamoya arteriopathy and aneurysms), and brain bleeding. Both epidemiology, pathophysiology, and treatment issues are addressed and prevention of cerebrovascular events, including silent cerebral infarctions, is particularly relevant in SCD patients, being associated to poor functional outcome and cognitive complaints. Transfusions and hydroxyurea are the main available therapy at the moment, but contraindications, availability, and complications might prevent their long term use, particularly in low-income countries. The role of transcranial Doppler in monitoring the patients (mainly children) is analyzed and a practical approach has been selected in order to give the main messages from the current literature for a better management of SCD patients.

Acute chest syndrome in sickle cell disease.

Sickle cell disease (SCD) is an autosomal recessive disorder altering the shape of red blood cells, causing harmful obstructions in blood vessels, therefore altering normal blood flow. SCD can escalate quickly into acute chest syndrome (ACS), a life-threatening complication that requires immediate care. This article discusses the pathophysiology, assessment, diagnosis, and treatment of ACS, as well as nursing care and patient education.

Heme- and iron-activated macrophages in sickle cell disease: an updated perspective.

Sickle cell disease (SCD) is a hereditary blood disorder due to a single-point mutation in the β-globin gene. The ensuing hemoglobin has the tendency to polymerize upon deoxygenation, leading to the typical sickle shape of red blood cells. While the primary pathology of sickle cell disease is a direct consequence of altered red blood cells, emerging evidence highlights the central role of macrophages in mediating hemoglobin scavenging, perpetuating oxidative stress and inflammation, and causing endothelial dysfunction and tissue remodeling. Recent research uncovered the impact of heme and iron overload on macrophage polarization and functions in sickle cell disease, and its implication for chronic inflammation and tissue damage in vital organs such as the liver, spleen, lungs and kidneys. By providing a thorough understanding of the dynamic interactions between macrophages and various cellular components within the sickle cell disease milieu, these studies have laid the foundation for the identification of macrophage-related cellular and molecular mechanisms potentially targetable for therapeutic purposes to attenuate sickle complications. This review provides a current update about recent discoveries on heme/iron-activated macrophages in SCD, shedding light on their critical role in disease pathophysiology. Ultimately, it proposes avenues for future research aimed at addressing the relevance of these cells for other sickle complications and at targeting them to mitigate disease morbidity and improve patient outcomes.

The Association Between Dental Caries and Salivary Buffering Capacity in Syrian Patients Diagnosed with Sickle Cell Disease.

Background Sickle cell disease (SCD) is a genetic disorder caused by mutations in the HBB gene, resulting in the abnormal shape of red blood cells. This condition is accompanied by various oral manifestations including salivary gland dysfunction leading to a heightened susceptibility to dental caries. This disorder is primarily treated with hydroxyurea. This study aims to assess dental caries utilizing the decay, missing, filling teeth (DMFT) index and evaluate salivary buffering capacity in patients diagnosed with SCD (HbSS type). The study also aims to assess the relationship between DMFT and salivary buffering capacity. Additionally, the study aimed to find a correlation between treatment with hydroxyurea and changes in both dental caries and salivary buffering capacity. Methods This case-control study enrolled a total of 100 participants aged between 20 and 50 years. The participants were divided into two groups: the study group, which comprised 70 individuals diagnosed with SCD (HbSS type), who were asked to report their current use of hydroxyurea, and the control group, which included 30 healthy individuals. Dental caries were assessed using the DMFT index, while salivary buffering capacity was measured using a pH meter model 420A device. Results The study group exhibited a mean DMFT index value of 6.39 compared to 5.20 in the control group. This difference was statistically significant (P-value=0.037), indicating higher DMFT values among patients with SCD. Salivary buffering capacity was significantly lower in the study group compared to the control group, with average values of 6.47 and 6.88, (P-value=.022). Interestingly, the administration of hydroxyurea impacted salivary buffering capacity, resulting in lower values for individuals using the drug (P-value=0.039). Conversely, hydroxyurea did not have a significant effect on DMFT values (P-value=0.317). Conclusion SCD increases susceptibility to dental caries and is associated with significant changes in salivary composition. At the same time, the potential negative impact of hydroxyurea is acknowledged.

Geometrical characterization of healthy red blood cells using digital holographic microscopy and parametric shape models for biophysical studies and diagnostic applications

Modeling of the red blood cell (RBC) shape is an integral part of the experimental and computer simulation investigations of light scattering by these cells for fundamental studies as well as diagnostic applications in techniques like cytometry and quantitative phase imaging. In the present work, a comprehensive study of the geometrical characterization of healthy human RBCs using digital holographic microscopy (DHM) and six frequently employed parametric shape models is reported. It is shown that the comparison of the optical phase profiles, and the thickness profiles given by the models with the DHM results gives a better judgment of the appropriateness of the parametric shape models. It is also shown that the RBC parametric models offer a simpler solution to the refractive index-thickness decoupling problem in QPI methods. Results of geometrical characterization of 500 healthy RBCs in terms of volume, surface area (SA), and sphericity index (SI) led to the classification of the parametric models in two categories based on the nature of variation of these quantities with the cell diameter. In light of the variability of the healthy RBC shapes, our findings suggest that the parametric models exhibiting a negative correlation between the SI and the cell diameter would provide more reliable estimates of the RBC parameters in diagnostic applications. Statistical distributions and descriptive statistics of the RBC volume, SA and SI serve as a guide for the assessment of the capability of the studied parametric models to give a reliable account of the variability of the healthy RBC shape and size.

A facile strategy for designing hollow-porous polymer microparticles with tunable structures

Biodegradable hollow-porous microparticles have shown great potentials in chemical and biomedical areas owing to their distinctive structural attributes. Herein, a simple but instructive strategy was proposed to construct hollow-porous polylactic acid (PLA) microparticles in one-step based on electrohydrodynamic atomization technology. Hollow-porous microparticles with fusiform, red blood cell and spherical shapes were successfully fabricated with production rates of 70 mg/h, 30 mg/h and 105 mg/h. A formation map in terms of flow rate ratio and PLA concentration was obtained to demonstrate the operating regions. Effects of key operating parameters were studied, showing that high voltage (11.4 kV−12.4 kV) and low PLA concentration conditions (2.5 %−3.5 %) are preferred to get well-structured particles. The evolutions of Taylor cone and atomization state were also explored experimentally and numerically to further understand the process. The prepared microparticles exhibit excellent sustained release performance and high encapsulation rate (>90 %). This strategy offers a satisfactory one-step method for preparing various structured hollow-porous polymer particles as drug carriers.

Detection of sickle cell disease using deep neural networks and explainable artificial intelligence

Abstract Sickle cell disease (SCD), a blood disorder that transforms the shape of red blood cells into a distinctive sickle form, is a major concern as it not only compromises the blood’s oxygen-carrying capacity but also poses significant health risks, ranging from weakness to paralysis and, in severe cases, even fatality. This condition not only underscores the pressing need for innovative solutions but also encapsulates the broader challenges faced by medical professionals, including delayed treatment, protracted processes, and the potential for subjective errors in diagnosis and classification. Consequently, the application of artificial intelligence (AI) in healthcare has emerged as a transformative force, inspiring multidisciplinary efforts to overcome the complexities associated with SCD and enhance diagnostic accuracy and treatment outcomes. The use of transfer learning helps to extract features from the input dataset and give an accurate prediction. We analyse and compare the performance parameters of three distinct models for this purpose: GoogLeNet, ResNet18, and ResNet50. The best results were shown by the ResNet50 model, with an accuracy of 94.90%. Explainable AI is the best approach for transparency and confirmation of the predictions made by the classifiers. This research utilizes Grad-CAM to interpret and make the models more reliable. Therefore, this specific approach benefits pathologists through its speed, precision, and accuracy of classification of sickle cells.

Comparison and evaluation of the methods for measuring hemolytic activity of <i>Stomolophus meleagris</i> jellyfish tentacle extract

Hemolytic activity assessment is a widely used method to evaluate the toxicity of marine organisms, including jellyfish. However, there are some challenges associated with testing hemolytic activity. In this study, four methods were employed to compare the hemolytic activity of jellyfish tentacle extract (TE). Firstly, a microplate reader was used to compare the mouse hemoglobin solution at three different wavelengths (415 nm, 541 nm, and 576 nm), and the most sensitive wavelength was selected for further experiments. Secondly, photomicrograph counting was used to determine the number of complete red blood cells in the field of view. Thirdly, a microplate reader was used to test hemolytic activity in a 96-well plate at 415 nm. Fourthly, a Bicinchoninic Acid (BCA) kit was used to test the concentration of hemoglobin in the solution. Finally, a UV-Vis Spectrophotometer was used to test hemolytic activity at 415 nm. Among the three wavelengths tested, the absorption value was most sensitive at 415 nm. The photomicrograph counting method was able to reflect changes in the shape of Red Blood Cells (RBCs). The microplate reader method may exhibit deviations when the solution concentration is high, while external factors could influence the BCA kit when the toxin concentration in the experimental group is low. The spectrophotometer method was found to be relatively accurate and sensitive to changes. When optimizing the method, it is important to consider the applicability of the Beer-Lambert law and the concentration of solutions.

Confinement effect on the microcapillary flow and shape of red blood cells.

The ability to change shape is essential for the proper functioning of red blood cells (RBCs) within the microvasculature. The shape of RBCs significantly influences blood flow and has been employed in microfluidic lab-on-a-chip devices, serving as a diagnostic biomarker for specific pathologies and enabling the assessment of RBC deformability. While external flow conditions, such as the vessel size and the flow velocity, are known to impact microscale RBC flow, our comprehensive understanding of how their shape-adapting ability is influenced by channel confinement in biomedical applications remains incomplete. This study explores the impact of various rectangular and square channels, each with different confinement and aspect ratios, on the in vitro RBC flow behavior and characteristic shapes. We demonstrate that rectangular microchannels, with a height similar to the RBC diameter in combination with a confinement ratio exceeding 0.9, are required to generate distinctive well-defined croissant and slipper-like RBC shapes. These shapes are characterized by their equilibrium positions in the channel cross section, and we observe a strong elongation of both stable shapes in response to the shear rate across the different channels. Less confined channel configurations lead to the emergence of unstable other shape types that display rich shape dynamics. Our work establishes an experimental framework to understand the influence of channel size on the single-cell flow behavior of RBCs, providing valuable insights for the design of biomicrofluidic single-cell analysis applications.

Biophysical chemistry behind sickle cell anemia and the mechanism of voxelotor action

Sickle cell anemia disease has been a great challenge to the world in the present situation. It occurs only due to the polymerization of sickle hemoglobin (HbS) having Pro–Val–Glu typed mutation, while the polymerization does not occur in normal hemoglobin (HbA) having Pro–Glu–Glu peptides. It is also well confirmed that the oxygenated HbS (OHbS) does not participate in the polymerization, while the deoxygenated HbS (dHbS) does, which causes the shape of red blood cells sickled. After polymerization, the blood has a low oxygen affinity. Keeping this fact into consideration, only those drugs are being synthesized that stabilize the OHbS structure so that the polymerization of HbS can be stopped. The literature data showed no systematic description of the changes occurring during the OHbS conversion to dHbS before polymerization. Hence, an innovative reasonable study between HbA and HbS, when they convert into their deoxygenated forms, was done computationally. In this evaluation, physiochemical parameters in HbA/HbS before and after deoxygenation were studied and compared deeply. The computationally collected data was used to understand the abnormal behaviour of dHbS arising due to the replacement of Glu6 with Val6. Consequently, during the presented computational study, the changes occurring in HbS were found opposite/abnormal as compared to HbA after the deoxygenation of both. The mechanism of Voxelotor (GBT-440) action to stop the HbS polymerization was also explained with the help of computationally collected data. Besides, a comparative study between GBT-440 and another suggested drug was also done to know their antisickling strength. Additionally, the effect of pH, CO, CO2, and 2,3-diphosphoglycerate (2,3-DPG) on HbS structure was also studied computationally.

Treatment of sickle cell anemia using CRISPR and prime editing

Sickle cell disease is a hereditary blood disease caused by an invisible genetic mutation on the autosome, caused by a transversion mutation in which the 6th amino acid of the -peptide chain, glutamate, is replaced by valine, resulting in the formation of sickle hemoglobin, instead of normal hemoglobin. Due to genetic mutations leading to structural abnormalities in hemoglobin and morphological changes in red blood cells, red blood cells lose their deformability in hypoxic environments, leading to vascular blockage, causing severe pain and partial tissue ischemia in patients. Oxygen needs to be transported to various parts of the body through red blood cells, thereby affecting the transportation of oxygen in the body. In general, red blood cells are circular and elastic, making them easy to move in blood vessels. However, in sickle cells, these red blood cells are compressed and deformed, causing the transportation of oxygen in the blood to become stiff and viscous, potentially slowing or blocking blood flow. The most common complication of SCA is blockage of blood vessels, which leads to pain. Although this is a complex phenomenon, HbS aggregation is a fundamental pathological physiological phenomenon in SCA. HbS aggregation can lead to malignant changes in the shape and physical properties of red blood cells, leading to hemolytic anemia and preventing blood flow, especially in small blood vessels, which may damage some organs. Clinical manifestations include anemia, immunodeficiency, multiple organ damage, severe acute and chronic pain, and premature death. The quality of life of the patients was seriously affected.

Changes to the shape, orientation and packing of red cells as a function of retinal capillary size.

The free diameter of a red blood cell exceeds the lumen diameter of capillaries in the central nervous system, requiring significant deformation of cells. However the deformations undertaken in vivo are not well established due to the difficulty in observing cellular capillary flow in living human tissue. Here, we used high resolution adaptive optics imaging to non-invasively track 17,842 red blood cells in transit through 121 unique capillary segments of diameter 8 µm or less in the retina of 3 healthy human subjects. Within each vessel, a 2D en face profile was generated for the "average cell", whose shape was then inferred in 3D based on the key assumption of a circular capillary cross-section. From this we estimated the average volume, surface area, orientation, and separation between red cells within each capillary tube. Our results showed a network filtration effect, whereby narrower vessels were more likely to contain smaller cells (defined by surface area, which is thought not to vary during a cell's passage through the vascular system). A bivariate linear model showed that for larger cells in narrower vessels: cells re-orient themselves to align with the flow axis, their shape becomes more elongated, there are longer gaps between successive cells, and remarkably, that cell volume is less which implies the ejection of water from cells to facilitate capillary transit. Taken together, these findings suggest that red cells pass through retinal capillaries with some reluctance. A biphasic distribution for cell orientation and separation was evident, indicating a "tipping point" for vessels narrower than approx. 5 µm. This corresponds closely to the typical capillary lumen diameter, and may maximize sensitivity of cellular flow to small changes in diameter. We suggest that the minimization of unnecessary oxygen exchange, and hence of damage via reactive oxygen pathways, may have provided evolutionary pressure to ensure that capillary lumens are generally narrower than red blood cells.

Implementación de la PCR digital para el diagnóstico prenatal no invasivo de la enfermedad de células falciformes. Estudio piloto

Sickle Cell Disease (SCD) is one of the most prevalent autosomal recessive disease, affecting over 600,000 newborns globally each year. In Spain, the Spanish Registry of Hemoglobinopathies (REHem) has registered 1142 cases. Despite improvements in treatments, prophylaxis, and vaccines, it remains a chronic condition requiring lifelong care. Allogeneic transplantation is the only cure, contingent upon the availability of an HLA-compatible donor. SCD is considered a rare disease in some population, resulting from a mutation of a single nucleotide in codon 6 GAG>GTG (HBB: c.20A>T) of the β-globin gene, producing hemoglobin S (HbS), altering the shape of red blood cells and obstructing circulation, leading to severe complications in multiple organs. Heterozygous individuals (βS/βA) have the ‘sickle cell trait,’ typically asymptomatic. Homozygotes experience symptomatic disease, with chronic and acute infarctions in organs and tissues, episodes of intense pain, cerebral infarctions, splenomegaly, massive hemolytic episodes, and acute chest syndrome, causing a risk of premature death increasing the threat of premature mortality. Prenatal diagnosis provides expecting couples with information about the fetus’s genetic health, enabling informed decision-making. Although conventional techniques are invasive and carry risks, Non-Invasive Prenatal Diagnosis (NIPD) has been developed using cell free fetal DNA (cffDNA) in maternal blood to determine the fetus’s genotype. However, the co-presence of maternal DNA and cffDNA, along with the low concentration of the latter, has been a challenge in non-invasive studies. We present the results of a pilot study where the use of digital PCR (dPCR) has been established for NIPD of SCD, a highly sensitive technique allowing the detection of mutations in low-frequency samples, presenting itself as a safe alternative for SCD diagnosis.

Management of Delayed Hemolytic Transfusion Reaction in a Patient with Sickle Cell Disease: A Case Report

Background: Sickle cell disease (SCD) is a group of inherited blood disorders characterized by abnormalities in hemoglobin (Hb), leading to distortion in shape of red blood cells (RBCs) and their breakdown, potentially blocking blood flow and resulting in pain and anemia. This can significantly impact the patient’s quality of life. Patients often require multiple blood transfusions to prevent complications associated with SCD by reducing the concentration of damaged hemoglobin. However, one of the significant complications of blood transfusions is Delayed Hemolytic Transfusion Reaction (DHTR), which occurs due to RBC alloimmunization (i.e., formation of antibodies against donor RBC antigens). DHTR can manifest as a sudden decrease in hemoglobin levels, which may progress to rapid multiorgan failure and death. Thus, prompt diagnosis is crucial for timely management. This case report highlights the diagnosis and management of a 56-year-old African American female with SCD who presented with bilateral severe knee pain and low Hb levels. Case Presentation: The patient’s symptoms, past medical history, and investigation findings led to a diagnosis of DHTR. Management was conducted within the framework of Bloodless Medicine, incorporating strategies to minimize blood loss and optimize erythropoiesis. Treatment included the use of erythropoietin (EPO) to manage hemoglobin levels and the administration of opioids and supplemental oxygen for symptom relief. Conclusion: Our case report highlights the challenges and various management strategies employed in treating DHTR in SCD patients. It emphasizes the importance of early recognition of the complication and compares the risks and benefits of additional blood transfusions in such patients. By presenting this case, we aim to contribute to the growing literature on DHTR in SCD patients and highlight the need for further research and optimized management strategies in this population.

Arginine supplementation improves lactate dehydrogenase levels in steady-state sickle cell patients: preliminary findings from Kinshasa, the Democratic Republic of Congo.

Sickle cell disease (SCD) disrupts oxygen transport due to the abnormal shape and rigidity of red blood cells, leading to hemolysis. Hemolysis, a major co-morbidity in SCD, is indicated by elevated levels of lactate dehydrogenase (LDH). Arginine depletion, which is essential for nitric oxide (NO) synthesis, contributes to various complications in SCD. L-arginine supplementation may increase NO levels and reduce oxidative stress. Research on its benefits in SCD, which is prevalent in sub-Saharan Africa, is limited. This study evaluates the effect of arginine supplementation on LDH levels in patients with steady state SCD. In a retrospective study, we evaluated the effect of arginine supplementation on LDH levels in a cohort of 31 patients. We divided the study into three phases: pre-HU treatment, HU treatment, and combined HU and arginine supplementation. The cohort had a median age of 12 years, ranging from 2 to 43 years. Throughout all three phases of the study, lactate dehydrogenase (LDH) levels were consistently above the established normal ranges, with elevations of 216.7%, 220.3% and 176.6% above the normative values for baseline, Phase 1 (HU) and Phase 2 (HU + Arg), respectively. Specifically, LDH levels were 649.7 ± 364.2 U/L in Baseline Phase, 661.6 ± 367 U/L in Phase 1, and 529.9 ± 346.3 U/L in Phase 2. When comparing these discrete study intervals, it is noteworthy that LDH levels were significantly lower in Phase 2 compared to the previous phases (p = 0.002). Preliminary findings revealed a significant lower LDH levels among sickle cell patients receiving combined arginine supplementation and hydroxyurea (HU). Although these findings are promising, their credibility and applicability require further and more extensive research.