Current and novel therapies for the prevention of vaso-occlusive crisis in sickle cell disease

Malnutrition in sickle cell anemia: Prevalence, impact, and interventions: A Review

Sickle Cell Anemia (SCA) is a hereditary hemoglobinopathy characterized by chronic hemolytic anemia, vaso-occlusive events, and a wide range of clinical complications. Malnutrition, often an underexplored aspect of this complex condition, plays a critical role in disease management and overall patient well-being. This publication provides a comprehensive review of the prevalence, impact, and interventions related to malnutrition in individuals with SCA. A thorough literature review reveals the multifaceted challenges faced by SCA patients in maintaining adequate nutrition. The pathophysiology of SCA, involving chronic inflammation, oxidative stress, and hypermetabolism, contributes to increased nutritional requirements and altered dietary patterns. Factors such as reduced appetite, nutrient malabsorption, dietary restrictions, and socioeconomic disparities further exacerbate the risk of malnutrition. Malnutrition is a prevalent issue among individuals with SCA, affecting patients of different age groups and disease severities. Nutritional deficiencies, including vitamins, minerals, and essential nutrients, are common in this population. The impact of malnutrition on disease outcomes is significant, with associations between nutrient status and complications such as pain crises, infections, and impaired quality of life. This paper also reviews nutritional interventions aimed at addressing malnutrition in SCA patients. While dietary counseling, supplementation, and personalized nutrition plans have shown promise in improving nutritional status, challenges such as patient adherence and access to healthcare must be addressed to optimize their effectiveness.

A comparison of the mixed and sequential use of acetaminophen and dexketoprofen in painful vaso-occlusive crises

PURPOSE

Opioids are widely used to treat painful vaso-occlusive crises (VOC) in sickle cell disease (SCD). However, due to opioids' significant adverse effect profiles, the search for alternative therapies continues from the past to the present. The study aimed to investigate the efficacy of acetaminophen and dexketoprofen in the treatment of painful VOC.

METHODS

This study is a single-center, prospective, non-randomized, single-blinded, controlled study. The study comprised two groups: the first administered acetaminophen and dexketoprofen mixed group, while the second received them sequential group. Opioids were used in patients with persistent pain despite these analgesics. Demographic and laboratory information, pain scores, opioid requirement, dose amount, side effects, and length of hospital stay of the patients were recorded.

RESULTS

The study comprised 56 (100%) patients with painful VOC, 29 (51.8%) from the mixed group, and 27 (48.2%) from the sequential group. Opioid use was seen in 16 (55.2%) patients in the mixed group and 21 (77.8%) patients in the sequential group (p = 0.074). The median amount of opioid used was significantly lower in the mixed group than in the sequential group (p < 0.001). Also, the median length of hospital stay was significantly lower in the mixed group than in the sequential group (p < 0.001).

CONCLUSION

Our study suggests that administering acetaminophen and dexketoprofen in the mix for the treatment of painful VOC in patients with SCD may be a more efficient approach compared to sequential administration. This approach appears to reduce opioid usage and shorten hospital stays.

Clinical Biomarkers of Acute Vaso-Occlusive Sickle Cell Crisis

It is known that an inherited blood condition called sickle cell disease (SCD) is a result of one gene. A number of blood and urine biomarkers have been determined in association with lab and clinical history for SCD patients. SCD has numerous interacting pathways associated with it, which have been identified by biomarkers. These mechanisms consist of some examples, such as endothelial vasodilation response, hypercoagulability, hemolysis, inflammation, oxidative stress, vascular dysfunction, and reperfusion injury among others. To effectively manage SCD, a comprehensive panel of validated blood and urine biomarkers must be established. Despite its monogenic inheritance, the complex nature of the SCD phenotype has impeded progress in its treatment. However, significant strides have been made in clinical biotechnology, paving the way for potential breakthroughs. In SCD, a panel of verified blood and urine biomarkers must be established, however. Despite monogenic inheritance, the great complexity of the SCD phenotype has hindered progress in its management. With few exceptions, clinical biomarkers of illness severity have been found through epidemiological investigations; nevertheless, systematic integration of these biomarkers into clinical treatment algorithms has not occurred. Furthermore, sickle cell crisis, the primary acute consequence of SCD, has been difficult to diagnose with the biomarkers now in use. Inadequate care and a lack of appropriate outcome measures for clinical research are the consequences of these diagnostic constraints. A new chapter in SCD customized treatment has begun with recent advancements in molecular and imaging diagnostics. Strategies in precision medicine are especially relevant now that molecular therapies are within reach. The significance of biochemical indicators linked to clinical manifestation and sub-phenotype identification in SCD is reviewed in this research.

Regional anesthesia and sickle cell crisis in pediatric patients: An educational-focused review

INTRODUCTION

Sickle cell disease (SCD) is the most common inherited hemoglobinopathy, affecting approximately 100 000 patients in United States and millions worldwide. Although the mainstay of pain management for VOC remains systemic opioids, given the potential for adverse effects including respiratory depression and hypoxemia, there remains interest in the use of regional anesthetic techniques (neuraxial or peripheral nerve blockade).

METHODS

A systematic search of pubMed, Scopus, and Google Scholar was conducted using the terms sickle cell disease, sickle cell crisis, pain crisis, vaso-occlusive crisis, regional anesthesia, peripheral nerve blockade, and neuraxial anesthesia.

RESULTS

We identified 7 publications, all of which were retrospective case series or single case reports, outlining the use of neuraxial anesthesia in a total of 26 patients with SCD. Additionally, we identified 4 publications, including one retrospective case series and 3 single case reports, entailing the use of peripheral blockade in patients with VOC and SCD.

DISCUSSION

The available literature, albeit all retrospective or anecdotal, suggests the potential utility of regional anesthesia to treat pain in patients with SCD. Additional benefits have included avoidance of the potential deleterious physiologic effects of systemic opioids and in one case series, an improvement in respiratory function as judged by pulse oximetry. The anecdotal and retrospective nature of the available reports with an absence of prospective trials limits the evidence based medicine available from which to develop to guidlines for the optimal local anesthetic agent to use, its concentration, the rate of infusion, and the choice of adjunctive agents.

How I treat sickle cell disease in pregnancy

ABSTRACT

Fifty years ago, people with sickle cell disease (SCD) were discouraged from becoming pregnant, but now, most should be supported if they choose to pursue a pregnancy. They and their providers, however, should be aware of the physiological changes of pregnancy that aggravate SCD and pregnancy's unique maternal and fetal challenges. Maternal problems can arise from chronic underlying organ dysfunction such as renal disease or pulmonary hypertension; from acute complications of SCD such as acute anemia, vaso-occlusive crises, and acute chest syndrome; and/or from pregnancy-related complications such as preeclampsia, sepsis, severe anemia, thromboembolism, and the need for cesarean delivery. Fetal problems include alloimmunization, opioid exposure, fetal growth restriction, preterm delivery, and stillbirth. Before and during pregnancy, in addition to the assessment and care that every pregnant patient should receive, patients with SCD should be evaluated and treated by a multidisciplinary team with respect to their unique maternal and fetal issues.

The Burden of Sickle Cell Disease on Children and Their Caregivers: Caregiver Reports of Children's Health-Related Quality of Life and School Experiences, Caregiver Burden, and Their Association with Frequency of Vaso-Occlusive Crises

Background

Children with sickle cell disease (SCD) experience a multiplex of disease-related symptoms and complications, including vaso-occlusive crises (VOCs), episodes characterized by extreme pain.

Methods

A cross-sectional observational survey examined the health-related quality of life (HRQoL) and school experiences of children with SCD 2 months-11 years, burden experienced by their caregivers, and associations between these outcomes and VOC frequency. Caregivers (N=167) of children with SCD in the US completed the Infant-Toddler Quality of Life-Short Form 47 (ITQoL-SF47) for children 2 months-4 years, the Child Health Questionnaire-Parent Form 50 (CHQ-PF50) and PROMIS Pain Interference and Sleep Disturbance Parent Proxy short forms for children 5-11 years, and a study-specific survey of school experiences.

Results

Children with SCD 2 months-4 years had lower ITQoL-SF47 scores (ie, worse HRQoL, p<0.001) than a normative sample of children; across domains, differences ranged from 18.73-45.03 points and exceeded minimal important difference (MID) thresholds. Except for the behavior domain, children with SCD 5-11 years had lower scores on all CHQ-PF50 domains than the normative sample (p<0.001); differences ranged from 6.78-36.37 points and exceeded MID thresholds. Children with more frequent VOCs had lower HRQoL and worse school experiences than children with less frequent VOCs (p<0.05, except for behavior domains). The largest differences based on VOC frequency were observed for overall health and bodily pain/discomfort among children 2 months-4 years (differences=40.88 and 32.50 points, respectively), and bodily pain and role/social limitations due to physical health among children 5-11 years (differences=38.99 and 37.80, respectively). Caregivers of children with more frequent VOCs experienced greater burden than caregivers of children with less frequent VOCs, though specific areas of impact (eg, caregiver emotions, time) differed across child age groups.

Conclusion

VOC frequency is negatively associated with HRQoL, highlighting the burden experienced by children with SCD and their caregivers.

A 21-Year-Old Woman with Sickle Cell Disease and Vaso-Occlusive Pain Associated with Using an Electronic Nicotine Dispensing System (E-Cigarette or Vape) - a Case Report

BACKGROUND Sickle cell disease is an inherited blood disorder that leads to multisystem complications. The heterogeneous course of sickle cell disease is due to both genetic modifiers and environmental factors. Cigarette smoking is a strong risk factor for sickle cell complications and even secondhand exposure to tobacco smoke can be detrimental for individuals with sickle cell disease. However, no prior reports have associated e-cigarettes and sickle cell vaso-occlusive pain. CASE REPORT A 21 year old woman presented with sickle cell disease SS complicated by frequent pain, multiple acute chest syndrome episodes, sickle cell nephropathy, and avascular necrosis of the left hip, plus mild intermittent asthma. She developed pain in the ribs and back after her first use of e-cigarettes. After 4 days of home pain management, she came to the Emergency Department. She was mildly hypoxic and received supplemental oxygen. Chest radiograph did not show airspace consolidation, and the sites of pain were consistent with her prior pain episodes, so the diagnosis was sickle cell vaso-occlusive pain. Her hemoglobin was more than 2 g/dL below baseline and she received a red blood cell transfusion on hospital day 2. Overall, this was among her more severe pain episodes. CONCLUSIONS The rising popularity of e-cigarettes, also known as vapes or Electronic Nicotine Delivery Systems (ENDS), is partly due to the misconception that they are safer than traditional cigarettes. Although firm conclusions will depend on studies designed to provide rigorous evidence, this case suggests that the acute adverse effects of ENDS might trigger complications of sickle cell disease, especially with asthma as a comorbidity.

Analysis of the 2007-2018 National Health Interview Survey (NHIS): Examining Neurological Complications among Children with Sickle Cell Disease in the United States

This study compared neurological complications among a national sample of United States children with or without sickle cell disease (SCD) and evaluated health status, healthcare and special education utilization patterns, barriers to care, and association of SCD status and demographics/socioeconomic status (SES) on comorbidities and healthcare utilization. Data was acquired from the National Health Interview Survey (NHIS) Sample Child Core questionnaire 2007-2018 dataset that included 133,542 children. An affirmation from the guardian of the child determined the presence of SCD. Regression analysis was used to compare the associations between SCD and demographics/SES on neurological conditions at p < 0.05. Furthermore, adjusted odds ratios (AORs) were estimated for having various neurological conditions. Of the 133,481 children included in the NHIS, the mean age was 8.5 years (SD: 0.02) and 215 had SCD. Of the children with SCD, the sample composition included male (n = 110), and Black (n = 82%). The SCD sample had higher odds of having neuro-developmental conditions (p < 0.1). Families of Black children (55% weighted) reported household incomes < 100% of federal poverty level. Black children were more likely to experience longer wait times to see the doctor (AOR, 0.3; CI 0.1-1.1). Compared to children without SCD, those with SCD had a greater chance of seeing a medical specialist within 12 months (AOR 2.3; CI 1.5-3.7). This representative sample of US children with SCD shows higher odds of developing neurological complications, increased healthcare and special education services utilization, with Black children experiencing a disproportionate burden. This creates the urgency to address the health burden for children with SCD by implementing interventions in healthcare and increasing education assistance programs to combat neurocognitive impairments, especially among Black children.

CRISPR/Cas9-based gene-editing technology for sickle cell disease

Sickle cell disease (SCD) is the most common monogenic hematologic disorder and is essentially congenital hemolytic anemia caused by an inherited point mutation in the β-globin on chromosome 11. Although the genetic basis of SCD was revealed as early as 1957, treatment options for SCD have been very limited to date. Hematopoietic stem cell transplantation (HSCT) was thought to hold promise as a cure for SCD, but the available donors were still only 15% useful. Gene therapy has advanced rapidly into the 21st century with the promise of a cure for SCD, and gene editing strategies based on the cluster-based regularly interspaced short palindromic repeat sequence (CRISPR)/Cas9 system have revolutionized the field of gene therapy by precisely targeting genes. In this paper, we review the pathogenesis and therapeutic approaches of SCD, briefly summarize the delivery strategies of CRISPR/Cas9, and finally discuss in depth the current status, application barriers, and solution directions of CRISPR/Cas9 in SCD. Through the review in this paper, we hope to provide some references for gene therapy in SCD.

Characterisation of medical conditions of children with sickle cell disease in the USA: findings from the 2007-2018 National Health Interview Survey (NHIS)

OBJECTIVES

We used the National Health Interview Survey (NHIS) data set to examine the prevalence of comorbid medical conditions; explore barriers to accessing healthcare and special educational services; and assess the associations between sickle cell disease (SCD) status and demographics/socioeconomic status (SES), and social determinants of health (SDoH) on comorbidities among children in the USA.

DESIGN

Cross-sectional.

SETTING

NHIS Sample Child Core questionnaire 2007-2018 data set.

PARTICIPANTS

133 481 children; presence of SCD was determined by an affirmative response from the adult or guardian of the child.

MAIN OUTCOME MEASURES

Multivariate logistic regression was used to compare the associations between SCD status, SES and SDoH for various medical conditions for all races and separately for black children at p<0.05.

RESULTS

133 481 children (mean age 8.5 years, SD: 0.02), 215 had SCD and ~82% (weighted) of the children with SCD are black. Children with SCD were more likely to suffer from comorbid conditions, that is, anaemia (adjusted OR: 27.1, p<0.001). Furthermore, children with SCD had at least two or more emergency room (ER) visits (p<0.001) and were more likely to have seen a doctor 1-15 times per year (p<0.05) compared with children without SCD. Household income (p<0.001) and maternal education were lower for children with SCD compared with children without SCD (52.4% vs 63.5% (p<0.05)). SCD children with a maternal parent who has < / > High School degree were less likely to have no ER visits or 4-5 ER visits, and more likely to have 2-3 ER visits within 12 months.

CONCLUSION

Children with SCD experienced significant comorbid conditions and have high healthcare usage, with black children being disproportionately affected. Moreover, maternal education status and poverty level illustrates how impactful SES can be on healthcare seeking behaviour for the SCD population. SDoH have significant implications for managing paediatric patients with SCD in clinical settings.

Patient-Reported Experiences in Voxelotor-Treated Children and Adults with Sickle Cell Disease: A Semistructured Interview Study

Objective

Voxelotor is a first-in-class sickle hemoglobin-polymerization inhibitor that was approved in 2019 by the US Food and Drug Administration for treatment of patients with sickle cell disease (SCD) aged ≥12 years; in 2021, the approval was extended to children with SCD aged 4 to 11 years. Additionally, both the Ministry of Health and Prevention for the United Arab Emirates and the European Commission granted marketing authorization for voxelotor in September 2021 and February 2022, respectively, for treatment of SCD in adults and pediatric patients aged ≥12 years. Thus, additional information on the patient experience with voxelotor would be useful for patients, caregivers, and healthcare professionals alike. The purpose of this study was to conduct semistructured interviews in an effort to understand the experiences and perspectives of voxelotor-treated patients with SCD.

Methods

One-time semistructured interviews with adults, adolescents, and children with SCD and their primary caregivers were conducted in the United States. Twenty-three adults and adolescents were recruited across 4 clinical sites, and 10 children-caregiver dyads were recruited from a single site. The interview was designed to elicit patient perspectives on symptomatic changes with voxelotor and the impact of treatment on patients' perceived health-related quality of life. Individual interview transcripts were analyzed using a thematic analytic approach, and concept saturation was assessed in both cohorts.

Results

Most patients reported improvements in their SCD symptoms with voxelotor treatment, specifically regarding pain crises, jaundice, and fatigue. Almost all patients experienced improvements in self-reported health-related quality of life with voxelotor treatment.

Conclusions

This study provides patient and caregiver perspectives on the symptomatic benefits of voxelotor treatment. These findings not only highlight the benefits of voxelotor treatment in improving symptoms and increasing health-related quality of life across the entire SCD population but also can inform further research on SCD-specific patient-reported outcomes.

Treatment patterns and burden of complications associated with sickle cell disease: A US retrospective claims analysis

Complications associated with sickle cell disease (SCD) that are highly impactful for patients but until recently have been less understood include priapism, nephropathy, and neurologic injury. We conducted a retrospective study using US administrative claims data from July 01, 2013 through March 31, 2020 to analyze incidence of these complications, SCD treatment patterns, and healthcare resource utilization (HCRU) and costs among 2524 pediatric and adult patients with SCD (mean [SD] age 43.4 [22.4] years). The most common treatments during follow-up were short-acting opioids (54.0% of patients), red blood cell transfusion (15.9%), and hydroxyurea (11.0%). SCD complications occurred frequently; in the overall population, the highest follow-up incidences per 1000 person-years were for acute kidney injury (53.1), chronic kidney disease (40.6), and stroke (39.0). Complications occurred across all age groups but increased in frequency with age; notably, acute kidney injury was 69.7 times more frequent among ages 65+ than ages 0-15 (p < 0.001). Follow-up per-patient-per-month HCRU also increased with age; however, all-cause healthcare costs were similarly high for all age groups and were driven primarily by inpatient stays. Patients with SCD across the age spectrum have a high burden of complications with the use of current treatments, suggesting unmet needs for treatment management.

Complete Neurologic Recovery of Cerebral Fat Embolism Syndrome in Sickle Cell Disease

Sickle cell disease is one of the most common inherited hemoglobinopathies diagnosed in the United States. Patients often present with severe anemia, pain crises, infections, and vaso-occlusive phenomena. Complications of these disorders can lead to significant debilitating morbidity and mortality. Fat embolism syndrome (FES) is a rare and devastating complication of sickle cell disease. It usually presents with a rapidly deteriorating clinical course, and the prognosis is dismal. We report a case of FES in a 19-year-old African American male with a history of sickle cell disease who presented with tonic-clonic seizures and was found to have multi-organ failure. FES was diagnosed 20 days from a presentation based on blood cytopenias and magnetic resonance imaging findings that were obscured at the initial presentation. We describe in this report, the patient’s course from presentation until diagnosis and resolution. Our case is peculiar as the patient had a very good outcome without the need for red blood cell (RBC) exchange; instead, supportive treatment and simple RBC transfusions were enough to change the clinical course of this almost fatal syndrome.

Extracellular Vesicles in Sickle Cell Disease: A Promising Tool

Sickle cell disease (SCD) is the most common hemoglobinopathy worldwide. It is characterized by an impairment of shear stress-mediated vasodilation, a pro-coagulant, and a pro-adhesive state orchestrated among others by the depletion of the vasodilator nitric oxide, by the increased phosphatidylserine exposure and tissue factor expression, and by the increased interactions of erythrocytes with endothelial cells that mediate the overexpression of adhesion molecules such as VCAM-1, respectively. Extracellular vesicles (EVs) have been shown to be novel actors involved in SCD pathophysiological processes. Medium-sized EVs, also called microparticles, which exhibit increased plasma levels in this pathology, were shown to induce the activation of endothelial cells, thereby increasing neutrophil adhesion, a key process potentially leading to the main complication associated with SCD, vaso-occlusive crises (VOCs). Small-sized EVs, also named exosomes, which have also been reported to be overrepresented in SCD, were shown to potentiate interactions between erythrocytes and platelets, and to trigger endothelial monolayer disruption, two processes also known to favor the occurrence of VOCs. In this review we provide an overview of the current knowledge about EVs concentration and role in SCD.

Novel Strategies for the Treatment of COVID-19

On 4 September, 2020, the US National Institutes of Health launched a new clinical trial, “A Multicenter, Adaptive, Randomized Controlled Platform Trial of the Safety and Efficacy of Antithrombotic and Additional Strategies in Hospitalized Adults with COVID-19.” This open-label, placebo-controlled, multicenter, adaptive platform study was designed to evaluate therapeutic options for patients hospitalized with mild, moderate, or severe COVID-19. A variety of drugs and drug classes were selected, including heparin, the monoclonal antibody crizanlizumab, sodium-glucose cotransporter-2 inhibitors, and purinergic signaling receptor Y₁₂ inhibitors. These medications have been widely used in the treatment of other conditions, from sick cell disease to type 2 diabetes mellitus and some forms of cardiovascular disease, but their inclusion in a study of COVID-19 was somewhat unexpected. This article examines the rationale behind the use of these disparate agents in the treatment and prevention of adverse outcomes in patients with COVID-19 and explores how these strategies may be utilized in the future to address the severe acute respiratory syndrome coronavirus 2 pandemic.

"Into the Lion's Den": COVID-19 Experiences of Black Adults with Sickle Cell Disease

Adults living with sickle cell disease are at risk for experiencing severe illness from coronavirus disease 2019 (COVID-19) due to the complexity of their disease. Additionally, self-management and navigating the healthcare system may be challenging during the COVID-19 pandemic. Therefore, we conducted telephone interviews with 25 participants to explore the experiences of Black adults living with sickle cell disease during the early months of the pandemic in the United States. Three overarching themes characterize their experiences: management of sickle cell disease was further complicated by the pandemic, fear of the virus contributed to physical and social isolation, and employment and financial challenges affected well-being. The pandemic contributed to changes in health care maintenance and had a disproportionate impact on this population. Addressing social and structural determinants of health and disruptions in health care accessibility is critical to advancing health and health care equity for individuals living with sickle cell disease.

Real-world effectiveness of voxelotor for treating sickle cell disease in the US: a large claims data analysis

BACKGROUND

Sickle cell disease (SCD) is a genetic disease that impacts patients' quality of life, healthcare costs, and life expectancy. Elevated sickle hemoglobin (HbS), which readily polymerizes, causes red blood cell sickling, leading to chronic hemolytic anemia and complications often requiring hospitalization and transfusions. In 2019, voxelotor, which inhibits HbS polymerization, was approved for SCD treatment.

OBJECTIVES

This study uses real-world evidence to assess voxelotor's effectiveness in SCD patients in typical clinical practice from 2019 to 2021 using a national medical claims database (N = 3128).

RESULTS

After initiating voxelotor, 60.8% of patients with available hemoglobin (Hb) laboratory data (n = 74) showed a Hb increase >1 g/dL. Mean transfusion rate per patient-year dropped 52% in patients with ≥1 transfusion before treatment (n = 190). In patients with ≥1 of the corresponding events (n = 1065), decreases were observed in mean vaso-occlusive crisis (VOC) frequency (-23%); mean VOC-related hospitalizations and length of stay (LOS) time (-34% and -30%, respectively); mean all-cause hospitalization and LOS time (-37% and -23%, respectively); outpatient visits (-10%); iron chelation use (-46%); and prescribed opioids (-13%).

CONCLUSION

These data align with randomized controlled trial results showing voxelotor improvements and support that voxelotor may lower transfusion and VOC rates in clinical practice.

Impact of hemoglobin biophysical studies on molecular pathogenesis and drug therapy for sickle cell disease

Basic research on hemoglobin has been essential for understanding the origin and treatment of many hematological disorders due to abnormal hemoglobins. The most important of the hemoglobinopathies is sickle cell disease - Linus Pauling's "molecular disease" that gave birth to molecular medicine. In this review, I will describe the contributions of basic biophysical research on normal and sickle cell hemoglobin (HbS) to understanding the molecular pathogenesis of the disease and providing the conceptual basis for the various approaches to drug therapy that target HbS polymerization. Most prominent among these are the experimental results on the solubility of HbS as a function of oxygen saturation explained by the allosteric model of Monod, Wyman, and Changeux and the Gill-Wyman thermodynamic linkage relation between solubility and oxygen binding, the solubility of mixtures of HbS with normal or fetal hemoglobin explained by Minton's thermodynamic model, and the highly unusual kinetics of HbS polymerization explained by a novel double nucleation mechanism that also accounts for the aggregation kinetics of the Alzheimer's peptide. The HbS polymerization kinetics are of great importance to understanding the pathophysiology and clinical course, as well as guiding drug development for treating this common and severe disease. The article focuses primarily on experimental and theoretical results from my lab, so it is not a comprehensive review of the subject.

Cell and Gene Therapy for Anemia: Hematopoietic Stem Cells and Gene Editing

Hereditary anemia has various manifestations, such as sickle cell disease (SCD), Fanconi anemia, glucose-6-phosphate dehydrogenase deficiency (G6PDD), and thalassemia. The available management strategies for these disorders are still unsatisfactory and do not eliminate the main causes. As genetic aberrations are the main causes of all forms of hereditary anemia, the optimal approach involves repairing the defective gene, possibly through the transplantation of normal hematopoietic stem cells (HSCs) from a normal matching donor or through gene therapy approaches (either in vivo or ex vivo) to correct the patient’s HSCs. To clearly illustrate the importance of cell and gene therapy in hereditary anemia, this paper provides a review of the genetic aberration, epidemiology, clinical features, current management, and cell and gene therapy endeavors related to SCD, thalassemia, Fanconi anemia, and G6PDD. Moreover, we expound the future research direction of HSC derivation from induced pluripotent stem cells (iPSCs), strategies to edit HSCs, gene therapy risk mitigation, and their clinical perspectives. In conclusion, gene-corrected hematopoietic stem cell transplantation has promising outcomes for SCD, Fanconi anemia, and thalassemia, and it may overcome the limitation of the source of allogenic bone marrow transplantation.

Biophysical and rheological biomarkers of red blood cell physiology and pathophysiology

PURPOSE OF REVIEW

This review summarizes the significant biophysical and rheological aspects of red blood cell physiology and pathophysiology in relation to recent advances in microfluidic biomarker assays and emerging targeted or curative intent therapies.

RECENT FINDINGS

Alterations in red cell biophysical properties and blood rheology have been associated with numerous hematologic and circulatory disorders. Recent advances in biomarker assays enable effective assessment of these biophysical and rheological properties in normoxia or physiological hypoxia in a clinically meaningful way. There are emerging targeted or curative therapies that aim to improve red cell pathophysiology, especially in the context of inherited hemoglobin disorders, such as sickle cell disease.

SUMMARY

Red cell pathophysiology can be therapeutically targeted and the improvements in membrane and cellular biophysics and blood rheology can now be feasibly assessed via new microfluidic biomarker assays. Recent advances provide a new hope and novel treatment options for major red cell ailments, including inherited hemoglobin disorders, membrane disorders, and other pathologies of the red cell, such as malaria.