Destruction Of Red Blood Cells Research Articles

Plain language summary: treatment of paroxysmal nocturnal hemoglobinuria with pegcetacoplan for 48 weeks (PEGASUS study)

What is this summary about? Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, serious blood disease, characterized by uncontrolled activation of the complement system that causes hemolysis (destruction of red blood cells). The complement component 5 (C5) inhibitor eculizumab was the first approved treatment for PNH. The PEGASUS trial compared eculizumab with pegcetacoplan, a new complement component 3 (C3) inhibitor. Because C3 is activated before C5, blocking C3 would also block C5; thus, a C3 inhibitor might prevent hemolysis more completely than a C5 inhibitor in patients with PNH. During the first 16 weeks of PEGASUS, patients received either pegcetacoplan or eculizumab; results were published separately. This summary describes results of the following 32 weeks of PEGASUS, during which all patients received pegcetacoplan to evaluate if pegcetacoplan continued to be effective and safe for up to 48 weeks. What were the results? Pegcetacoplan continued to be effective in participants who received it throughout the study and improved symptoms in participants who switched from eculizumab. The most common adverse events (side effects) were skin irritation at the injection site, hemolysis, nasopharyngitis (runny nose and sore throat), and diarrhea. Adverse events were serious and related to pegcetacoplan in 4 of 77 (5%) patients; all patients recovered from these events. What do the results mean? Pegcetacoplan improved symptoms and was well tolerated for up to 48 weeks by most patients in PEGASUS, suggesting that adult patients with PNH may benefit from long-term pegcetacoplan treatment.

β-Thalassemia gene editing therapy: Advancements and difficulties.

β-Thalassemia is the world's number 1 single-gene genetic disorder and is characterized by suppressed or impaired production of β-pearl protein chains. This results in intramedullary destruction and premature lysis of red blood cells in peripheral blood. Among them, patients with transfusion-dependent β-thalassemia face the problem of long-term transfusion and iron chelation therapy, which leads to clinical complications and great economic stress. As gene editing technology improves, we are seeing the dawn of a cure for the disease, with its reduction of ineffective erythropoiesis and effective prolongation of survival in critically ill patients. Here, we provide an overview of β-thalassemia distribution and pathophysiology. In addition, we focus on gene therapy and gene editing advances. Nucleic acid endonuclease tools currently available for gene editing fall into 3 categories: zinc finger nucleases, transcription activator-like effector nucleases, and regularly interspaced short palindromic repeats (CRISPR-Cas9) nucleases. This paper reviews the exploratory applications and exploration of emerging therapeutic tools based on 3 classes of nucleic acid endonucleases in the treatment of β-thalassemia diseases.

Changes in liver and kidney function, red blood cell count and hemoglobin levels 1 day after ultrasound-guided percutaneous microwave ablation for uterine fibroids.

To investigate the changes in liver and kidney function, red blood cell (RBC) count and hemoglobin (HGB) levels in patients undergoing ultrasound-guided percutaneous microwave ablation (UPMWA) for uterine fibroids on postoperative day 1. The changes in liver and kidney function, RBC count and HGB levels in 181 patients who underwent selective UPMWA in the Second Affiliated Hospital of Shantou University Medical College, China, between August 2017 and January 2023 were retrospectively analyzed. All patients underwent UPMWA for uterine fibroids; 179 patients had multiple uterine fibroids and 2 patients had single uterine fibroids. The maximum fibroid diameter ranged from 18 to 140 mm, with an average of 68.3 mm. Ultrasound imaging was used to confirm that the blood flow signal within the mass had disappeared in all patients, indicating that the ablation was effective. Within 24 h, compared with before UPMWA, levels of total bilirubin, direct bilirubin, indirect bilirubin and aspartate aminotransferase had significantly increased (p < 0.01), whereas levels of total protein, albumin, globulin, alanine aminotransferase, creatinine and urea had significantly decreased (p < 0.01). Acute kidney injury (AKI) occurred in 1 of the 181 patients. The RBC count and HGB levels decreased significantly after UPMWA (p < 0.01). Ultrasound-guided percutaneous microwave ablation for uterine fibroids can impose a higher detoxification load on the liver and cause thermal damage to and the destruction of RBCs within local circulation, potentially leading to AKI. Protein levels significantly decreased after UPMWA. Therefore, perioperative organ function protection measures and treatment should be actively integrated into clinical practice to improve prognosis and enhance recovery.

Fabrication and characterization of TiO2‐hydroxyapatite composite‐loaded Polysulfone membranes with integrated biocompatibility for dialysis application

AbstractBackgroundThe use of Polysulfone (PSf) as membrane material for dialysis therapy is becoming more common. However, the PSf membrane can cause the adsorption of blood proteins followed by the adhesion of platelets, destruction of red blood cells, and thrombus formation. One of the biggest challenges in creating membranes for hemodialysis (HD) applications is ensuring biocompatibility. Therefore, to maintain the biocompatibility of PSf membranes, further modifications are necessary.MethodsIn this study, the performance and biocompatibility of PSf membranes were improved by the impregnation of TiO2‐hydroxyapatite composite as an additive. The TiO2‐hydroxyapatite composite was first synthesized via sintering at 1200°C, and then a dope solution composed of pristine PSf polymer solution in N‐Methyl‐2‐pyrrolidone solvent (NMP) and different wt% ratios of the synthesized composite were prepared, and resultant membranes were fabricated using a film applicator via a phase inversion scheme using water as a non‐solvent exchange medium. The synthesized composite was characterized using SEM, EDX, and XRD techniques.ResultsThe FTIR analysis confirmed the weak interaction of PSf polymer with the hydroxyapatite moiety of the composite. The interaction of the synthesized composite within the membrane matrix was evaluated via leaching ratio results. The hydrophilicity, pore profile, and pure water permeation flux rates were also determined. The results of the biocompatibility study showed that membranes based on TiO2‐hydroxyapatite composite had reduced adsorption of BSA protein by 34.41% as well as less than 5% hemolysis ratio. Additionally, the study displayed thrombus formation ranging from 2.08% to 8.69%, respectively. The dialysis results indicated that compared with the original PSf membrane, the TiO2‐hydroxyapatite composite showed high clearance rates for urea (73.81%) and creatinine (72.13%) solutes, respectively.ConclusionTherefore, blending TiO2‐hydroxyapatite composite in the PSf membrane significantly improved the biocompatibility and removal ability of uremic solutes.

Induced magnetic force and curvature effect of ternary hybrid nanofluid (jeffrey model) in ciliary peristaltic channels

ABSTRACT Ternary hybrid nanoparticles require infected blood cell base fluid flow. Blood vessels feature ciliated walls and peristaltic waves. Anemia comes from cancer treatment-induced red blood cell destruction. This study reproduces Jeffrey model blood flow through a ciliary peristaltic artery using ternary hybrid nanoparticles of gold, iron oxide, and copper. This work examines ternary hybrid nanofluid MHD ciliary peristaltic motion using Jeffrey curves. A nonlinear PDE system has heat and induced magnetic force equations. The Adomian Decomposition Method solved this system without long-wavelength approximation. Visualize how essential biological and physical elements affect velocity, temperature, trapping, magnetic force contours, induced magnetic field components, axial pressure, and normal pressure. Flow, temperature, magnetic features, and other important properties are plotted and discussed against biological and biomedical parameters. We discovered full consistency with modest scenario efforts. The increase in nanoparticles gives ternary hybrid nanofluid a larger friction force than hybrid, so its axial pressure gradient at the wall is stronger, decays at hybrid, decays further from nanofluid to base fluid, and reverses at the intermediate area. Peristaltic ciliary activity alters magnetic force contours, shrinks loops, and forms four contour groups with different implications.

Autoimmune Hemolytic Anemia: A Review

Autoimmune hemolytic anemia (AIHA) is defined as an anemia caused by the destruction of red blood cells by antibodies directed against the patient's own red blood cell surface antigens. Different forms of AIHA are distinguished based on the characteristics of the antibody responsible for the disease. The most common form (70% of cases) is warm antibody autoimmune hemolytic anemia. These antibodies become active at temperatures between 35°C and 40°C. This type of hemolysis occurs mainly within tissues, particularly in the spleen. The diagnosis of AIHA relies on rigorous interpretation of immunohematological parameters, as well as additional tests to exclude associated diseases. In "idiopathic" cases, it is recommended to continue monitoring elderly patients beyond remission to detect the possible occurrence of lymphoma or myelodysplastic syndrome. Corticosteroid therapy is the standard treatment, but it can lead to numerous side effects. The efficacy of rituximab appears particularly promising in "refractory" forms of AIHA, and its use in the early phase of management to spare corticosteroid therapy should be evaluated in a prospective and randomized study.

Evaluation of the impact of two C5 genetic variants on C5-eculizumab complex stability at the molecular level

Complement C5 is the target of the monoclonal antibody eculizumab, used in complement dysregulating disorders, like the rare disease Paroxysmal Nocturnal Hemoglobinuria (PNH). PNH is an acquired hematopoietic stem cell condition characterized by aberrant destruction of erythrocytes, chronic hemolytic anemia, and thromboembolism propensity. C5 is a protein component of the complement system which is part of the immune system of the body and plays a prominent role in the destruction of red blood cells, misidentifying them as a threat. This work describes the application of molecular dynamics simulations to the study of the underlying interactions between complement C5 and eculizumab. This study also reveals the importance of single nucleotide polymorphisms on C5 protein concerning the effective inhibition of the mAB, involving the mechanistic events taking place at the interface spots of the complex. The predicted conformational change in the C5 Arg885/His/Cys mutation has implications on the protein’s interaction with eculizumab, compromising their compatibility. The acquired insights into the conformational changes, dynamics, flexibility, and interactions shed light on the knowledge of the function of this biomolecule providing answers about the poor response to the treatment in PNH patient carriers of the mutations. By investigating the intricate dynamics, significant connections between C5 and eculizumab can be uncovered. Such insights may aid in the creation of novel compounds or lead to the enhancement of eculizumab’s efficacy. Communicated by Ramaswamy H. Sarma

A unique case series of pediatric autoimmune hemolytic anemia

BackgroundAutoimmune hemolytic anemia (AIHA) is a group of hematological disorders where there is autoantibody mediated destruction of red blood cells. It can be life threatening if not appropriately treated. Early diagnosis and work up and timely multipronged management is the key to success. Case reportWe report four cases of diverse etiology - one each of post SARS-CoV-2 AIHA, idiopathic AIHA, drug-induced AIHA and common variable immunodeficiency (CVID) associated Evans syndrome. All were treated with steroids as the first line agent while the child with CVID required additional immunosuppressive therapy. ConclusionThis case series re-emphasizes the need to look for diverse etiologies in AIHA. The role of whole exome sequencing is discussed for a definitive diagnosis if accessible in selected cases.

Mitapivat: New dawn in pyruvate kinase deficiency and beyond

Mitapivat is the first in class oral allosteric activator of pyruvate kinase enzyme, leading to increased ATP production. Since red blood cells (RBC) rely on anaerobic metabolism, converting phosphoenolpyruvate to pyruvate in Embden– Meyerhof glycolytic pathway is the most important step for ATP production. Deficiency of ATP in patients with pyruvate kinase deficiency (PKD) leads to the destruction of RBCs. In hemoglobinopathies, including thalassemia and sickle cell disease, increased stress and utilization leads to rapid depletion of ATP resources.Phase II DRIVE PK study was the first randomized controlled trial that showed benefits in adult patients without regular transfusion requirement in regards to a rise in hemoglobin ≥1.0 g/dl and improvement in other parameters of hemolysis even with a low 50 mg twice daily dose. Minor adverse effects, including headache, insomnia, and nausea were reported.Subsequent adult studies like ACTIVATE III (non-transfusion-dependent) and ACTIVATE III – T (transfusion-dependent) in patients with PKD showed sustained hemoglobin response in 16/40 (40%) patients. It was tolerated well, and the adverse effect profile was similar to the previous study except for hypertriglyceridemia and hypertension in two patients.Phase I/II trials on patients with thalassemia and sickle cell anemia have also shown promising results in reducing transfusion burden and other disease-related co-morbidities, paving the way for further studies.Mitapivat appears to be a safe, well-tolerated, and effective drug for PKD and other RBC pathologies in adults. Results of ongoing pediatric studies in these settings are awaited to reveal its safety profile in children.

A rare presentation of severe alloimmune hemolytic disease of newborn pertaining to minor blood group ‘c’ incompatibility: a case report and review of literature

Hyperbilirubinemia is one of the most widely seen causes of neonatal morbidity. Haemolytic disease of fetus and newborn is caused by maternal alloantibodies to the fetal RBCs. It is responsible for incompatibility between maternal and fetal blood groups, which results in destruction of fetal red blood cells causing hyperbilirubinemia. ABO and Rh incompatibility are the most common causes of severe indirect hyperbilirubinemia. Besides ABO and Rh isoimmunization, minor blood group incompatibilities such as anti-Kell, anti-C, anti-c, anti-E, anti MNS, Duffy, KIDD, P, Lutheran and Lewis have also been identified as causes of severe neonatal jaundice with an incidence of 385/1,00,000 live births in South-East Asia. We, hereby report a rare case of a full term 2.2 kg newborn presented with severe anemia with reticulocytosis and neonatal hyperbilirubinemia at second hour of life. In view of strongly positive DCT and no Rh negative or ABO setting, minor blood group incompatibility screening test was performed in the mother which revealed presence of multiple alloantibodies; however, the red cell phenotyping confirmed the presence of anti-c antibodies in maternal sera responsible for neonatal alloimmune haemolytic anemia. The baby was offered intensive phototherapy with intravenous immunoglobulin.

Hemolytic Disease in Newborn Due to Jka Antibody: A Unique Clinical Presentation

Hemolytic disease in newborn results from alloimmune-mediated destruction of fetal or neonatal red blood cells caused by maternal alloantibodies. While ABO and Rh (D) incompatibilities are common causes, other minor antigenic mismatches such as Kidd are relatively infrequent. Here, we report a case of a female infant displaying conjugated hyperbilirubinemia and hepato-splenomegaly. Lab tests revealed both mother’s and baby’s blood groups as A positive, along with elevated reticulocyte count and a positive direct antiglobulin test. An abdominal ultrasound unveiled inspissated bile syndrome, likely due to calcium bilirubin sludge, leading to the conjugated hyperbilirubinemia. Further assessment revealed the infant and the father had a JKa-positive RBC phenotype, while the mother had a JKa-negative phenotype. This case highlights the significance of blood group antigen beyond the Rh system as a potential cause of hemolytic disease in newborn.

A new role for erythropoietin in the homeostasis of red blood cells

The regulation of red blood cell (RBC) homeostasis is widely assumed to rely on the control of cell production by erythropoietin (EPO) and the destruction of cells at a fixed, species-specific age. In this work, we show that such a regulatory mechanism would be a poor homeostatic solution to satisfy the changing needs of the body. Effective homeostatic control would require RBC lifespan to be variable and tightly regulated. We suggest that EPO may control RBC lifespan by determining CD47 expression in newly formed RBCs and SIRP-α expression in sinusoidal macrophages. EPO could also regulate the initiation and intensity of anti-RBC autoimmune responses that curtail RBC lifespan in some circumstances. These mechanisms would continuously modulate the rate of RBC destruction depending on oxygen availability. The control of RBC lifespan by EPO and autoimmunity emerges as a key mechanism in the homeostasis of RBCs.

Wound Healing Potential of Different Extracts of Ehretia Laevis Roxb. (Khandu Chakka/Ajan Vruksha) Versus Silver Sulfadiazine in Burn Wound - Pre-Clinical Study

Burns are also a leading cause of morbidity; millions who survive suffer from lifelong disability and disfigurements with resulting emotional trauma and stigma. To identify the effective extract of Charma Vruksha( Ehretia Laveis Roxb.) in burn wound management and to generate empirical evidence for substantiation of burn wound healing by Kashaya Rasa ( Astringent taste) through experimental demonstration of the comparative wound healing property of Charma Vruksha ( Ehretia Laevis Roxb.) this study was planned. This study is useful in broadening of therapeutic aspect of Charma Vruksha( Ehretia Laveis Roxb.) plant. This is contribution to the literature related to ayurvedic sciences. The stated side effects of silver sulfadiazine like pain, burning, itching, rash, cell death, destruction of red blood cells (in patients with G6PD deficiency), deficiency of granulocytes in the blood, low blood platelet count, low white blood cell count , can be minimized to some extent by the use of Charma Vruksha( Ehretia Laveis Roxb.) plant leaves. Wound healing measured by histology score and wound contracture percentages. Average wound contracture percentage was 36.83 % in Crude Extract group, 33.75% in Ethanol Extract group, 34.6 % in Chloroform Extract group , 42.41% in Aqueous Extract group, as compared to 38.08 % of Silver sulfadiazine. Histological score was 16 in Crude Extract group, 15 in Ethanol Extract group,15 in Chloroform Extract group , 16 in Aqueous Extract group as compared to 18 of Silver sulfadiazine. Aqueous Extract was more effective in burn wound contracture by 11.37 % than Silver sulfadiazine Crude and Aqueous extract was more effective than ethanol and chloroform extract by 1 histological score but less effective by 2 histological score than Silver sulfadiazine.&#x0D; Aqueous Extract is more efficacious in burn wound contracture by 11.37 % than Silver sulfadiazine.

Primary autoimmune haemolytic anaemia is associated with increased risk of ischaemic stroke: A binational cohort study from Denmark and France.

Primary autoimmune haemolytic anaemia (AIHA) causes the destruction of red blood cells and a subsequent pro-thrombotic state, potentially increasing the risk of ischaemic stroke. We investigated the risk of ischaemic stroke in patients with AIHA in a binational study. We used prospectively collected data from nationwide registers in Denmark and France to identify cohorts of patients with primary AIHA and age- and sex-matched general population comparators. We followed the patient and comparison cohorts for up to 5 years, with the first hospitalization of a stroke during follow-up as the main outcome. We estimated cumulative incidence, cause-specific hazard ratios (csHR) and adjusted for comorbidity and exposure to selected medications. The combined AIHA cohorts from both countries comprised 5994 patients and the 81 525 comparators. There were 130 ischaemic strokes in the AIHA cohort and 1821 among the comparators. Country-specific estimates were comparable, and the overall adjusted csHR was 1.36 [95% CI: 1.13-1.65], p = 0.001; the higher rate was limited to the first year after AIHA diagnosis (csHR 2.29 [95% CI: 1.77-2.97], p < 10-9 ) and decreased thereafter (csHR 0.89 [95% CI: 0.66-1.20], p = 0.45) (p-interaction < 10-5 ). The findings indicate that patients diagnosed with primary AIHA are at higher risk of ischaemic stroke in the first year after diagnosis.

Breast Cancer and Autoimmune Hemolytic Anemia: A Rare Paraneoplastic Syndrome

Autoimmune hemolytic anemia (AIHA) is a pathological process involving the destruction of red blood cells by the humoral immune system. Although there is a well-established relationship between the presence of AIHA and lymphoproliferative malignancies, AIHA rarely presents in association with solid malignancies. Few cases of solid cancer associated with AIHA have been reported. AIHA rarely presents as a paraneoplastic syndrome indicative of solid cancer. We report a case of breast cancer revealed by AIHA.

Diagnosis and Treatment of Immune Heamolytic Aneamia

Immune hemolytic anemia (IHA) stands as a multifaceted hematologic disorder characterized by accelerated destruction of red blood cells due to immune system dysregulation. This paper aims to elucidate the nuanced landscape of IHA, focusing on its diverse diagnostic approaches and evolving treatment strategies. Diagnostic considerations encompass a range of laboratory tests, including direct and indirect Coombs tests, hemolysis markers, and autoimmune antibody panels, elucidating their roles in confirming IHA etiology and subtype classification. Additionally, advancements in imaging modalities aid in identifying underlying causative factors contributing to hemolysis. The paper further scrutinizes therapeutic interventions, spanning corticosteroids, immunosuppressive agents, and monoclonal antibodies, while also appraising emerging modalities like rituximab and splenectomy. Moreover, the role of supportive care and transfusion strategies in managing IHAassociated complications is delineated. Challenges in IHA management, including refractory cases and adverse effects of therapies, are deliberated alongside the potential of future advancements in precision medicine and targeted therapies. By assimilating the latest diagnostic methodologies and treatment paradigms, this review provides a comprehensive outlook on navigating the complexities of immune hemolytic anemia to optimize patient care and outcomes. Keywords: haemolytic anaemia, anaemia, immunity, diagnosis, treatment

Abstract B030: Intracerebral and intraventricular hemorrhage due to severe thrombocytopenia: A rare case of Evans syndrome

Abstract Introduction: Evans syndrome (ES) is a rare autoimmune disorder characterized by the development of autoimmune hemolytic anemia (AIHA), immune thrombocytopenia (ITP), and/or immune neutropenia (AIN) without an identifiable cause. It is believed to involve immune system dysregulation, leading to the destruction of red blood cells, platelets, and neutrophils. Case Presentation: A 68-year-old male with a history of coronary artery disease, hypertension, diabetes, and atrial fibrillation presented with abdominal pain and diarrhea. Laboratory tests revealed a platelet count of 3k, suggesting ITP. Initial treatment with dexamethasone and platelet transfusion provided limited improvement. A bone marrow biopsy showed mildly hypercellular bone marrow with trilineage hematopoiesis. However, the patient's condition rapidly deteriorated, and he returned to the emergency department with severe symptoms, including headache, gum bleeding, and lower extremity petechiae. A CT scan revealed a large intraparenchymal hematoma with intraventricular hemorrhage, highlighting the risk of life-threatening bleeding in ES patients. Discussion: The patient was managed with platelet transfusions, high-dose steroids, and intravenous immunoglobulin (IVIG), which provided temporary relief but failed to maintain stable platelet levels. Further investigations revealed a positive antinuclear antibody (ANA), suggesting an underlying rheumatological condition and confirming the diagnosis of secondary ES. This finding necessitated the exploration of treatment options. Of interest is Romiplostim (Promacta), a thrombopoietin receptor agonist, which has shown promise in increasing platelet counts and reducing bleeding episodes in refractory ITP. Considering the positive ANA and the suspected rheumatological etiology, Romiplostim may serve as a viable long-term treatment option to stabilize platelet levels and mitigate bleeding risks in this case. Conclusion: This case highlights the complexity of Evans syndrome and emphasizes the need to promptly recognize and manage life-threatening bleeding complications, particularly in older patients. The presence of a positive ANA suggests an underlying rheumatological condition, necessitating comprehensive evaluation, and tailored therapeutic approaches. Although further research is needed to understand the pathogenesis and optimal management strategies for ES, Romiplostim holds promise as a potential treatment for patients with secondary ES who are unresponsive to conventional therapies. Citation Format: Kiersten R. Patterson, Aliya M. Khan, Raj Patel. Intracerebral and intraventricular hemorrhage due to severe thrombocytopenia: A rare case of Evans syndrome [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B030.

Gender Disparities in Outcomes of Autoimmune Hemolytic Anemia Admissions: An Analysis of the National Inpatient Sample

Introduction Autoimmune hemolytic anemia (AIHA) is a condition characterized by the immune destruction of red blood cells, which can necessitate hospitalization in severe cases. The purpose of this study is to compare outcomes of AIHA hospitalizations between genders. Methods We utilized the International Classification of Diseases (ICD) codes to identify all hospitalizations with the primary diagnosis of AIHA in the National Inpatient Sample (NIS) from 2002 to 2019. We excluded all pediatric (age &amp;lt; 18 years) and elective hospitalizations. We described the baseline characteristics of both groups including demographics and comorbidities. We fitted multivariable logistic regression models to compare outcomes between males and females while adjusting for age, race, and comorbidities. Results A total of 60,529 met the inclusion and exclusion criteria. The majority of these were females (59.1% vs 40.1%, p &amp;lt; 0.001). Males were older (median age 67 vs. 66 years, p &amp;lt; 0.001) and had more white race (73.4% vs. 67.9%, p &amp;lt; 0.001). The distribution of associated comorbidities also differed different between both groups ( (Table 1). On adjusted analysis, males had higher in-hospital mortality rates. They also had higher rates of most secondary outcomes; including rates of circulatory shock, need for mechanical ventilation, bacterial pneumonia, acute myocardial infarction, deep vein thrombosis, hemorrhagic stroke, acute kidney injury, and requiring new hemodialysis. Females had higher rates of urinary tract infections. No significant differences were found in the rates of requiring blood transfusions, sepsis, acute heart failure, pulmonary embolism, ischemic stroke, encephalopathy, and gastrointestinal bleeding (Figure 1). Furthermore, male hospitalizations were associated with higher costs (median [IQR] of $11,400 [6,700-20,500] vs. $10,000 [6,000- 17,200]) despite similar length of stay (median [IQR] of 4 days [3-7] vs. 4 days [3-7]). Conclusion Male patients hospitalized with AIHA experience poorer in-hospital compared to females. More research is essential to understand the underlying causes for these disparities and to tailor management to improve outcomes for both male and female AIHA patients.

Caspase-1 As a Therapeutic Target in Intravascular Hemolysis-Induced Microvascular Inflammation and Occlusive Processes

Hemolytic anemias, such as sickle cell disease (SCD), are a group of acute and acquired conditions characterized by the accelerated destruction of red blood cells (RBC). Intravascular hemolysis (IVH), or RBC lysis within the bloodstream, incurs the release of damage-associated molecular patterns (DAMPs), trigging cell activation and immune responses. Caspase-1 (Casp-1), a protease enzyme, plays a critical role during inflammatory processes by initiating programed cell death and promoting the cleavage of pro-interleukin (IL)-1β into its active form, IL-1β, through inflammasome assembly. Here, we aimed to elucidate the complex mechanisms involved in IVH-induced inflammation, leukocyte-endothelium interactions, and microvascular dynamics. Acute IVH was induced in C57BL/6 mice (HEM) by the injection of sterile water (i.v., 150 µl), and control mice received i.v. saline (CON) (n=3-8 per group). Intravital microscopy was performed at 15 min post IVH induction on the cremaster muscle of mice to quantify venular leukocyte (WBC) rolling and adhesion, and non-invasive laser Doppler flowmetry (LDF) measured blood perfusion in the murine pelvis microvasculature. Blood samples were collected at 1-hour post-IVH for ELISA and flow cytometry analyses. Immortalized human endothelial cells (HUVEC; n=7 per group) were stimulated with heme or S100A8 for 3 hours. HEM mice demonstrated significantly increased plasma heme (P&amp;lt;0.0001) and cell-free hemoglobin (P&amp;lt;0.001), in association with significantly decreased plasma haptoglobin (P&amp;lt;0.05), compared to CON mice, thereby confirming the occurrence of IVH. Furthermore, HEM mice exhibited significantly increased plasma concentrations of the S100A8 alarmin (P&amp;lt;0.001) and IL1-β (P&amp;lt;0.001), as well as augmentations (P&amp;lt;0.001) in plasma TNF-ɑ and IL-6 levels. Flow cytometry was used to measure active Casp-1 in neutrophils and monocytes of mice using the FAM-FLICA probe. FLICA staining was significantly higher in the neutrophils (P&amp;lt;0.05) and monocytes (P&amp;lt;0.05) of HEM mice, compared to CON mice, implying Casp-1 activation in these cell subsets. WBC-endothelium interactions are a hallmark of vaso-occlusion in SCD. HEM mice exhibited elevated venular WBC rolling and adhesion to the endothelium, compared to CON mice (P&amp;lt;0.001), as previously shown (Almeida et al., 2015; PMID: 26019278). In addition, IVH significantly reduced the velocity of microvascular blood flow in mice (P&amp;lt;0.001), and impaired perfusion (P&amp;lt;0.001). To address the role of IVH-induced Casp-1 activation in microvascular dynamics, mice received i.p. administrations of the Casp-1 inhibitor, YVAD, at 1 hour prior to induction of IVH, or not, and were subjected to intravital microscopy or LDF. Interestingly, the inhibition of Casp-1 significantly abrogated IVH-induced WBC rolling (P&amp;lt;0.01) and adhesion to vessel walls (P&amp;lt;0.05) in HEM mice and significantly improved microvascular blood perfusion and flow velocity (P&amp;lt;0.05), suggesting a role for Casp-1 activation in the WBC-endothelium and occlusive interactions observed (See Figure). We then evaluated how heme and S100A8 may induce endothelial cell activation, as these DAMPs were found elevated in the plasma of HEM mice. As expected, compared to unstimulated HUVEC, heme induced endothelial cell activation in vitro, as shown by higher expressions of ICAM-1 (P&amp;lt;0.05), VCAM-1 (P&amp;lt;0.01) and E-selectin (P&amp;lt;0.01), and increased Casp-1 activity (P&amp;lt;0.01). In turn, S100A8 alone significantly elevated ICAM-1 (P&amp;lt;0.05) and E-selectin (P&amp;lt;0.01) expressions on HUVEC, as well as IL-1β release (P&amp;lt;0.001), however no significant increase in Casp-1 activity was observed. HUVEC, when pre-treated with YVAD, displayed a significant reduction in S100A8-induced E-selectin expression (P&amp;lt;0.05), but neither ICAM-1 nor VCAM-1 expression were significantly decreased. In contrast, no changes in the expressions of these adhesion molecules were observed in heme-stimulated cells after YVAD treatment. Taken together, these findings suggest that targeting caspase-1 activation and its associated pathways may represent a potential therapeutic intervention to mitigate the adverse inflammatory and microvascular effects of IVH, a disease mechanism that occurs in severe hemolytic anemias such as SCD.

A Phase III Clinical Trial Program Investigating the Efficacy and Safety of Ianalumab in Patients with Primary Immune Thrombocytopenia (VAYHIT1 and VAYHIT2) and Warm Autoimmune Hemolytic Anemia (VAYHIA)

Background: Immune thrombocytopenia (ITP) and warm autoimmune hemolytic anemia (wAIHA) are characterized by autoantibody destruction of platelets and red blood cells, respectively. Autoreactive B cells play a role in the pathophysiology of ITP and wAIHA. Serum levels of B-cell activating factor (BAFF) are elevated in these disorders and correlate with increased disease activity. Ianalumab is a novel, fully human immunoglobulin G1 monoclonal antibody that targets BAFF receptor (BAFF-R) and has a unique dual mechanism of action: direct antibody-dependent cellular cytotoxicity-mediated B-cell depletion and inhibition of B-cell differentiation, proliferation and survival via blockade of BAFF-R-mediated signaling. Corticosteroids (CS) are the standard first-line treatment for ITP; however, few patients achieve a long-term response. Additionally, extended and recurrent use of CS is associated with substantial toxicity. Thrombopoietin receptor agonists (TPO-RAs), such as eltrombopag, are commonly used second-line ITP treatments and often achieve a response; however, responses are rarely maintained once treatment ends, so chronic administration is typically required. For wAIHA, few treatments have been approved, and patients rarely achieve durable responses on CS or off-label rituximab. Thus, there are significant unmet needs for patients with ITP or wAIHA. Aim: We report the designs of the randomized, double-blind, multicenter, 3-arm Phase III VAYHIT1 (NCT05653349), VAYHIT2 (NCT05653219) and VAYHIA (NCT05648968) trials. The trials aim to assess whether ianalumab, working with a distinct and complementary mechanism to standard-of-care treatments, can induce durable responses in patients with ITP or wAIHA. Trial designs: VAYHIT1 and VAYHIT2 will assess the efficacy and safety of ianalumab vs placebo in addition to first-line CS and short-term eltrombopag, respectively, in adults with primary ITP. In both trials, patients will be randomized 1:1:1 to intravenous (IV) low-dose ianalumab, high-dose ianalumab or placebo every 4 weeks (wks). The primary endpoint in both trials is the time from randomization to treatment failure, defined as platelet count &amp;lt;30 G/L later than 8 wks from randomization, need for rescue treatment later than 8 wks from randomization, start of a new ITP therapy, or death. In VAYHIT2, ineligibility to taper or inability to discontinue eltrombopag after the completion of treatment with ianalumab or placebo will also be assessed as treatment failure. Secondary endpoints include response rate, complete response rate and safety ( Table). VAYHIA will assess the efficacy and safety of ianalumab vs placebo in adults with wAIHA who have failed ≥1 treatment. Patients will be randomized 1:1:1 to IV low-dose ianalumab, high-dose ianalumab or placebo every 4 wks. Selected supportive care is allowed. The primary endpoint is durable hemoglobin (Hb) response, defined as Hb ≥10 g/dL and an Hb increase of ≥2 g/dL from baseline for ≥8 consecutive wks between Wk 9 and Wk 25 in the absence of rescue or prohibited treatment. The key secondary endpoint is duration of durable Hb response ( Table). An optional open-label crossover period will allow patients who receive placebo and do not achieve a durable Hb response to receive high-dose ianalumab. Patients from all 3 trials will be monitored for efficacy until treatment failure (or up to 39 months after the last patient was randomized, whichever comes first) and safety for up to 2 years. Conclusions: These trials have been designed based on the hypothesis that, when administered early in disease progression, medical therapy targeting complementary physiological pathways may restore self-tolerance in patients with ITP and wAIHA. Ianalumab in combination with standard of care is expected to safely induce a high response rate that will be maintained beyond treatment completion. Ianalumab may address the unmet needs for patients with ITP and wAIHA. Current status: At the time of writing, VAYHIT1, VAYHIT2 and VAYHIA are recruiting. The open-label, single-arm, Phase II VAYHIT3 trial is also assessing ianalumab in patients with primary ITP previously treated with at least 1 CS and 1 TPO-RA (NCT05885555).