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1.
Br J Haematol ; 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38797558

RESUMO

Distinguishing RALD from JMML can be difficult. This review discusses the clinical features, genetic aetiology and the treatments that are common and distinct between the two diagnoses.

2.
Res Pract Thromb Haemost ; 8(1): 102305, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38292347

RESUMO

Background: In hemophilia and von Willebrand disease, the degree of alteration of laboratory assays correlates with bleeding manifestations. Few studies have assessed the predictive value for bleeding of laboratory assays in patients with inherited platelet function disorders (IPFDs). Objectives: To assess whether there is an association between platelet function assay results and bleeding history, as evaluated by the International Society on Thrombosis and Haemostasis (ISTH) bleeding assessment tool (BAT). Methods: Centers participating in the international ISTH-BAT validation study were asked to provide results of the diagnostic assays employed for the patients they enrolled, and the association with the individual patients' bleeding score (BS) was assessed. Results: Sixty-eight patients with 14 different IPFDs were included. Maximal amplitude of platelet aggregation was significantly lower in patients with a pathologic BS and correlated inversely with the BS, a finding largely driven by the subgroup of patients with Glanzmann thrombasthenia and CalDAG-GEFI deficiency; after their exclusion, TRAP-induced aggregation remained significantly lower in patients with a pathologic BS. Bleeding time was significantly more prolonged in patients with a high BS than in those with a normal BS (27.1 ± 6.2 minutes vs 15.1 ± 10.6 minutes; P < .01). Reduced α-granule content was significantly more common among patients with a pathologic BS than among those with a normal BS (80% vs 20%; P < .05). Receiver operating characteristic curve analysis revealed a significant discriminative ability of all the aforementioned tests for pathologic BS (P < .001), also after exclusion of patients with Glanzmann thrombasthenia and CalDAG-GEFI deficiency. Conclusion: This study shows that altered platelet laboratory assay results are associated with an abnormal ISTH-BAT BS in IPFD.

3.
J Thromb Haemost ; 22(3): 645-665, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38016518

RESUMO

BACKGROUND: Inherited bleeding, thrombotic, and platelet disorders (BTPDs) are a heterogeneous set of diseases, many of which are very rare globally. Over the past 5 decades, the genetic basis of some of these disorders has been identified, and recently, high-throughput sequencing has become the primary means of identifying disease-causing genetic variants. OBJECTIVES: Knowledge of the clinical validity of a gene-disease relationship is essential to provide an accurate diagnosis based on results of diagnostic gene panel tests and inform the construction of such panels. The Scientific and Standardization Committee for Genetics in Thrombosis and Hemostasis undertook a curation process for selecting 96 TIER1 genes for BTPDs. The purpose of the process was to evaluate the evidence supporting each gene-disease relationship and provide an expert-reviewed classification for the clinical validity of genes associated with BTPDs. METHODS: The Clinical Genome Resource (ClinGen) Hemostasis/Thrombosis Gene Curation Expert Panel assessed the strength of evidence for TIER1 genes using the semiquantitative ClinGen gene-disease clinical validity framework. ClinGen Lumping and Splitting guidelines were used to determine the appropriate disease entity or entities for each gene, and 101 gene-disease relationships were identified for curation. RESULTS: The final outcome included 68 Definitive (67%), 26 Moderate (26%), and 7 Limited (7%) classifications. The summary of each curation is available on the ClinGen website. CONCLUSION: Expert-reviewed assignment of gene-disease relationships by the ClinGen Hemostasis/Thrombosis Gene Curation Expert Panel facilitates accurate molecular diagnoses of BTPDs by clinicians and diagnostic laboratories. These curation efforts can allow genetic testing to focus on genes with a validated role in disease.


Assuntos
Transtornos Plaquetários , Trombose , Humanos , Testes Genéticos/métodos , Transtornos Plaquetários/genética , Hemostasia/genética , Trombose/diagnóstico , Trombose/genética , Variação Genética
4.
Platelets ; 35(1): 2290108, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38099325

RESUMO

Previous research suggests that individuals with 22q11.2 deletion syndrome (DS) have an increased risk of bleeding following cardiac surgery. However, current guidelines for management of patients with 22q11.2DS do not provide specific recommendations for perioperative management. This study sought to identify specific risk factors for bleeding in this patient population. Examine the factors determining bleeding and transfusion requirements in patients with 22q11.2DS undergoing cardiac surgery. This was a single center review of patients who underwent cardiac surgery at the Children's Hospital of Philadelphia from 2000 to 2016. Data was extracted from the medical record. Frequency of bleeding events, laboratory values, and transfusion requirements were compared. We included 226 patients with 22q11.2DS and 506 controls. Bleeding events were identified in 13 patients with 22q11.2DS (5.8%) and 27 controls (5.3%). Platelet counts were lower among patients with 22q11.2DS than in control patients, but not statistically different comparing bleeding to not bleeding. Patients with 22q11.2DS received more transfusions (regardless of bleeding status). However, multivariate analysis showed only procedure type was associated with increased risk of bleeding (p = .012). The overall risk of bleeding when undergoing cardiac surgery is not different in patients with 22q11.2DS compared to non-deleted patients. Though platelet counts were lower in patients with 22q11.2DS, only procedure type was significantly associated with an increased risk of bleeding.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Síndrome de DiGeorge , Criança , Humanos , Síndrome de DiGeorge/complicações , Síndrome de DiGeorge/cirurgia , Estudos de Casos e Controles , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Estudos Retrospectivos , Contagem de Plaquetas
5.
J Mol Diagn ; 26(3): 191-201, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38103590

RESUMO

Inherited bone marrow failure syndromes (IBMFS) are a group of heterogeneous disorders that account for ∼30% of pediatric cases of bone marrow failure and are often associated with developmental abnormalities and cancer predisposition. This article reports the laboratory validation and clinical utility of a large-scale, custom-designed next-generation sequencing panel, Children's Hospital of Philadelphia (CHOP) IBMFS panel, for the diagnosis of IBMFS in a cohort of pediatric patients. This panel demonstrated excellent analytic accuracy, with 100% sensitivity, ≥99.99% specificity, and 100% reproducibility on validation samples. In 269 patients with suspected IBMFS, this next-generation sequencing panel was used for identifying single-nucleotide variants, small insertions/deletions, and copy number variations in mosaic or nonmosaic status. Sixty-one pathogenic/likely pathogenic variants (54 single-nucleotide variants/insertions/deletions and 7 copy number variations) and 24 hypomorphic variants were identified, resulting in the molecular diagnosis of IBMFS in 21 cases (7.8%) and exclusion of IBMFS with a diagnosis of a blood disorder in 10 cases (3.7%). Secondary findings, including evidence of early hematologic malignancies and other hereditary cancer-predisposition syndromes, were observed in 9 cases (3.3%). The CHOP IBMFS panel was highly sensitive and specific, with a significant increase in the diagnostic yield of IBMFS. These findings suggest that next-generation sequencing-based panel testing should be a part of routine diagnostics in patients with suspected IBMFS.


Assuntos
Anemia Aplástica , Doenças da Medula Óssea , Hemoglobinúria Paroxística , Humanos , Criança , Anemia Aplástica/diagnóstico , Anemia Aplástica/genética , Doenças da Medula Óssea/diagnóstico , Doenças da Medula Óssea/genética , Síndrome Congênita de Insuficiência da Medula Óssea , Variações do Número de Cópias de DNA/genética , Reprodutibilidade dos Testes , Hemoglobinúria Paroxística/diagnóstico , Hemoglobinúria Paroxística/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Nucleotídeos
6.
Ther Adv Hematol ; 14: 20406207231205431, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869360

RESUMO

Background: Immune thrombocytopenia (ITP) is characterized by primarily autoantibody-mediated platelet destruction and impaired platelet production resulting in thrombocytopenia and an increased risk of bleeding. Other manifestations include increased risk of thrombosis and diminished quality of life. Current treatment approaches are directed toward lowering the rate of platelet destruction or stimulating platelet production to prevent bleeding. Rilzabrutinib is an oral, reversible, potent Bruton tyrosine kinase inhibitor that was specifically designed to treat immune-mediated diseases and mediates its therapeutic effect through a dual mechanism of action: (1) inhibiting B-cell activation and (2) interrupting antibody-coated cell phagocytosis by Fc gamma receptor in spleen and liver. A 24-week dose-finding phase I/II study of rilzabrutinib in patients with ITP showed a 40% platelet response (⩾2 consecutive platelet counts of ⩾50 × 109/L and increase from baseline ⩾20 × 109/L without rescue medication use) and a well-tolerated safety profile with only grade 1/2 transient adverse events across dose levels. Objectives: Assess the efficacy and safety of oral rilzabrutinib in adult and adolescent patients with persistent or chronic ITP. Design: Rilzabrutinib 400 mg BID is being evaluated in the ongoing LUNA 3 multicenter, double-blind, placebo-controlled phase III study. Methods and analysis: The primary endpoint is durable platelet response, defined as achieving platelet counts of ⩾50 × 109/L for at least two-thirds of ⩾8 available weekly scheduled platelet measurements during the last 12 weeks (including ⩾2 available measurements within the last 6 weeks) of the 24-week blinded treatment period in the absence of rescue therapy. Ethics: Ethical guidelines and informed consent are followed. Discussion: The LUNA 3 trial will further investigate rilzabrutinib's safety and efficacy in adult and adolescent patients, with the primary goal of addressing a major objective in treating patients with ITP: durability of platelet response. Trail Registration: ClinicalTrials.gov NCT04562766: https://clinicaltrials.gov/ct2/show/NCT04562766; EU Clinical Trials Register EudraCT 2020-002063-60: https://www.clinicaltrialsregister.eu/ctr-search/search?query=2020-002063-60.

7.
Pediatr Blood Cancer ; 70(12): e30682, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37731177

RESUMO

BACKGROUND/OBJECTIVES: Pediatric patients with chronic immune thrombocytopenia (ITP) commonly have activity limitations placed to prevent injury without data guiding clinical decision-making. The objective of this study was to determine risk factors associated with injury in children with chronic ITP. DESIGN/METHODS: Retrospective single-center cohort study from January 1, 2008 to March 31, 2019 in subjects age 5-21 years with chronic ITP (platelet count < 100,000/µL for >1 year). RESULTS: One-hundred-two subjects were included, with a mean diagnosis age of 9.3 ± 4.6 years. Mean follow-up 3.8 ± 2.3 years; 61% (62) of subjects were female; 60% (61) participated in organized sports, mean 2 ± 1 sports/subject; 8.8% (9) received ITP therapy for sports participation. Common sports: basketball (28%) and soccer (28%). There were 31 injuries in 26 subjects, and 68% (21) occurred while at play. Most common injuries: 68% (21/31) soft tissue and 23% (7/31) head trauma. Fifteen (48%) injuries were severe enough for medical evaluation at the time of injury. Only one patient received acute ITP treatment for their injury. Injury was associated with participation in high-risk sports (p < .001), male sex (p = .007), and participation in multiple organized sports (p = .008). CONCLUSION: In this study of 102 pediatric subjects with chronic ITP, injury was mild and infrequent predominantly occurring while at play. The majority participated in organized sports safely. Risk of injury was associated with high-risk sport participation (p < .001). Only one injury necessitated ITP treatment, suggesting that participation in most sports is likely safe in children with chronic ITP.

9.
Br J Haematol ; 203(1): 17-22, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37641973

RESUMO

Immune thrombocytopenia (ITP) in children is a relatively mild and self-limited disorder with the majority of children demonstrating normalization of platelet count by 12 months from diagnosis. Because of this, many children with ITP can be observed without the need for treatment. When needed, treatment with either intravenous immunoglobulin (IVIG) or corticosteroids is highly effective (>80% IVIG and >95% corticosteroids). For those children who require second-line therapies, response rates of >60% are seen with both the thrombopoietin-receptor agonists and rituximab. Despite this, some children will have 'refractory' ITP (rITP) with poor or transient responses to platelet-raising therapies. Here, we review the clinical features of rITP in children, outline proposed classifications and explore potential predictors for children with rITP.


Assuntos
Púrpura Trombocitopênica Idiopática , Trombocitopenia , Criança , Humanos , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/terapia , Imunoglobulinas Intravenosas/uso terapêutico , Contagem de Plaquetas , Plaquetas
10.
Neonatology ; 120(5): 661-665, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37473739

RESUMO

Thrombocytopenia is a common laboratory abnormality encountered in critically ill neonates. The broad differential for thrombocytopenia, and its association with potentially severe neonatal pathology, often presents a diagnostic dilemma prompting extensive evaluation. Hemolysis due to red cell enzymopathies is a rare cause of neonatal thrombocytopenia that is typically brief and self-limiting. Here, we present a case of thrombocytopenia, refractory to transfusion, associated with anemia and hyperbilirubinemia in a neonate with pyruvate kinase deficiency (PKD) arising from compound heterozygous PKLR mutations. The nature of the thrombocytopenia in this patient created considerable diagnostic uncertainty, which was ultimately resolved by whole-exome sequencing. This case emphasizes that inherited red cell defects, such as PKD, are important to consider in cases of neonatal thrombocytopenia.


Assuntos
Anemia Hemolítica Congênita não Esferocítica , Anemia , Doenças do Recém-Nascido , Erros Inatos do Metabolismo dos Piruvatos , Trombocitopenia Neonatal Aloimune , Recém-Nascido , Humanos , Anemia Hemolítica Congênita não Esferocítica/complicações , Anemia Hemolítica Congênita não Esferocítica/diagnóstico , Anemia Hemolítica Congênita não Esferocítica/genética , Erros Inatos do Metabolismo dos Piruvatos/diagnóstico , Erros Inatos do Metabolismo dos Piruvatos/genética , Erros Inatos do Metabolismo dos Piruvatos/complicações , Piruvato Quinase/genética
11.
Res Pract Thromb Haemost ; 7(2): 100097, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37063755

RESUMO

The inaugural McMaster Immune Thrombocytopenia (ITP) Summit was held virually in 2021. The objectives of the Summit were to recognize the difficulties in establishing the diagnosis of ITP and to understand gaps in current knowledge of ITP mechanisms that might lead to better diagnostic approaches and treatments. The half-day program consisted of virtual educational sessions targeting clinicians and basic scientists. The planning committee chose 8 topics to review that would cover current knowledge and inform future research priorities. In this report, we summarized the presentations delivered at the 2021 McMaster ITP Summit and the discussions. Based on the information presented at the Summit, the following research priorities were identified: 1) investigation of platelet production as a target for ITP treatments; 2) characterization of antigen processing and antigen presentation on platelets; 3) interaction between megakaryocytes and the immune system; 4) the role for ITP gene panels; 5) the need for better methods for platelet antibody testing; 6) the role of prediction models for diagnosis and prognosis; 7) new treatment strategies, including intensification of initial therapy; and 8) personalized treatment algorithms.

12.
Genet Med ; 25(3): 100338, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36729053

RESUMO

This review aimed to update the clinical practice guidelines for managing children and adolescents with 22q11.2 deletion syndrome (22q11.2DS). The 22q11.2 Society, the international scientific organization studying chromosome 22q11.2 differences and related conditions, recruited expert clinicians worldwide to revise the original 2011 pediatric clinical practice guidelines in a stepwise process: (1) a systematic literature search (1992-2021), (2) study selection and data extraction by clinical experts from 9 different countries, covering 24 subspecialties, and (3) creation of a draft consensus document based on the literature and expert opinion, which was further shaped by survey results from family support organizations regarding perceived needs. Of 2441 22q11.2DS-relevant publications initially identified, 2344 received full-text reviews, including 1545 meeting criteria for potential relevance to clinical care of children and adolescents. Informed by the available literature, recommendations were formulated. Given evidence base limitations, multidisciplinary recommendations represent consensus statements of good practice for this evolving field. These recommendations provide contemporary guidance for evaluation, surveillance, and management of the many 22q11.2DS-associated physical, cognitive, behavioral, and psychiatric morbidities while addressing important genetic counseling and psychosocial issues.


Assuntos
Síndrome de DiGeorge , Adolescente , Humanos , Criança , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/terapia , Aconselhamento Genético , Inquéritos e Questionários
13.
Pediatr Blood Cancer ; 70(3): e30173, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36579787

RESUMO

Pediatric immune thrombocytopenia (ITP) is an acquired disorder associated with autoimmune destruction and impairment of platelet production in children. Some children exhibit poor or transient response to ITP-directed treatments and are referred to as having refractory ITP (rITP). There is currently no consensus on the definition of rITP, nor evidence-based treatment guidelines for patients with rITP. After a survey of pediatric ITP experts demonstrated lack of consensus on pediatric rITP, we pursued a systematic review to examine the reported clinical phenotypes and treatment outcomes in pediatric rITP. The search identified 253 relevant manuscripts; following review, 11 studies proposed a definition for pediatric rITP with no consensus amongst them. Most definitions included suboptimal response to medical management, while some outlined specific platelet thresholds to define this suboptimal response. Common attributes identified in this study should be used to propose a comprehensive definition, which will facilitate outcome comparisons of future rITP studies.


Assuntos
Púrpura Trombocitopênica Idiopática , Trombocitopenia , Humanos , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Trombocitopenia/complicações , Plaquetas , Resultado do Tratamento , Consenso
14.
Clin Genet ; 103(1): 109-113, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36075864

RESUMO

Prior studies have demonstrated that patients with chromosome 22q11.2 deletion syndrome (22q11.2DS) have lower platelet counts (PC) compared to non-deleted populations. They also have an increased mean platelet volume. The mechanism for this has been postulated to be haploinsufficiency of the GPIBB gene. We examined platelet parameters, deletion size and factors known to influence counts, including status of thyroid hormone and congenital heart disease (CHD), in a population of 825 patients with 22q11.2DS. We also measured surface expression of GPIB-IX complex by flow cytometry. The major determinant of PC was deletion status of GP1BB, regardless of surface expression or other factors. Patients with nested distal chromosome 22q11.2 deletions (those with GP1BB present) had higher PCs than those with proximal deletions where GP1BB is deleted. Patients with 22q11.2DS also demonstrated an accelerated PC decrease with age, occurring in childhood. These data demonstrate that genes within the proximal deletion segment drive PC differences in 22q11.2DS and suggest that PC reference ranges may need to be adjusted for age and deletion size in 22q11.2DS populations. Bleeding did not correlate with either platelet count or GPIb expression. Further studies into drivers of expression of GPIb and associations with severe thrombocytopenia and immune thrombocytopenia are needed to inform clinical care.


Assuntos
Síndrome de DiGeorge , Humanos , Síndrome de DiGeorge/genética
15.
Br J Haematol ; 200(2): 222-228, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36207145

RESUMO

Germline mutations in tubulin beta class I (TUBB), which encodes one of the ß-tubulin isoforms, were previously associated with neurological and cutaneous abnormalities. Here, we describe the first case of inherited bone marrow (BM) failure, including marked thrombocytopenia, morphological abnormalities, and cortical dysplasia, associated with a de novo p.D249V variant in TUBB. Mutant TUBB had abnormal cellular localisation in transfected cells. Following interferon/ribavirin therapy administered for transfusion-acquired hepatitis C, severe pancytopenia and BM aplasia ensued, which was unresponsive to immunosuppression. Acquired chromosome arm 6p loss of heterozygosity was identified, leading to somatic loss of the mutant TUBB allele.


Assuntos
Pancitopenia , Trombocitopenia , Humanos , Tubulina (Proteína)/genética , Pancitopenia/genética , Deleção Cromossômica , Trombocitopenia/genética , Transtornos da Insuficiência da Medula Óssea/genética , Células Germinativas
16.
Mol Genet Metab ; 136(4): 324-329, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35786528

RESUMO

BACKGROUND: Because of the broad clinical spectrum, heritable autoinflammatory diseases present a management and therapeutic challenge. The most common genetic interferonopathy, Aicardi Goutières Syndrome (AGS), is associated with early onset neurologic disability and systemic inflammation. The chronic inflammation of AGS is the result of dysregulation of interferon (IFN) expression by one of nine genes within converging pathways. While each AGS subtype shares common features, distinct patterns of severity and potential for systemic complications amongst the genotypes are emerging. Multilineage cytopenias are a potentially serious, but poorly understood, complication of AGS. As immunomodulatory treatment options are developed, it is important to characterize the role of the disease versus treatment in hematologic abnormalities. This will allow for better understanding and management of cytopenia. METHODS: In total, 142 individuals with molecularly-confirmed AGS were included. Information on genotype, demographics, and all available hematologic laboratory values were collected from existing medical records. As part of a clinical trial, a subset of this cohort (n = 52) were treated with a janus kinase inhibitor (baricitinib), and both pre- and post-treatment values were included. Abnormal values were graded based on Common Terminology Criteria for Adverse Events (CTCAE v5.0), supplemented with grading definitions for thrombocytosis, and were compared across genotypes and baricitinib exposure. RESULTS: In total, 11,184 laboratory values were collected over a median of 2.54 years per subject (range 0-22.68 years). To reduce bias from repeated sampling within a limited timeframe, laboratory results were restricted to the most abnormal value within a month (n = 8485). The most common abnormalities were anemia (noted in 24% of subjects prior to baricitinib exposure), thrombocytopenia (9%), and neutropenia (30%). Neutropenia was most common in the SAMHD1 cohort and increased with baricitinib exposure (38/69 measurements on baricitinib versus 14/121 while not on baricitinib). Having an abnormality prior to treatment was associated with having an abnormality on treatment for neutropenia and thrombocytopenia. CONCLUSION: By collecting available laboratory data throughout the lifespan, we were able to identify novel patterns of hematologic abnormalities in AGS. We found that AGS results in multilineage cytopenias not limited to the neonatal period. Neutropenia, anemia, and thrombocytopenia were common. Moderate-severe graded events of neutropenia, anemia, and leukopenia were more common on baricitinib, but rarely of clinical consequence. Based on these results, we would recommend careful monitoring of hematologic parameters of children affected by AGS throughout the lifespan, especially while on therapy, and consideration of AGS as a potential differential diagnosis in children with neurologic impairment of unclear etiology with hematologic abnormalities. Trial registration ClinicalTrials.gov Identifier: NCT01724580 ClinicalTrials.gov Identifier: NCT03921554.


Assuntos
Anemia , Neutropenia , Trombocitopenia , Doenças Autoimunes do Sistema Nervoso , Criança , Humanos , Recém-Nascido , Inflamação , Malformações do Sistema Nervoso
17.
Blood Adv ; 6(17): 5100-5112, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-35839075

RESUMO

Transcription factor RUNX1 is a master regulator of hematopoiesis and megakaryopoiesis. RUNX1 haplodeficiency (RHD) is associated with thrombocytopenia and platelet granule deficiencies and dysfunction. Platelet profiling of our study patient with RHD showed decreased expression of RAB31, a small GTPase whose cell biology in megakaryocytes (MKs)/platelets is unknown. Platelet RAB31 messenger RNA was decreased in the index patient and in 2 additional patients with RHD. Promoter-reporter studies using phorbol 12-myristate 13-acetate-treated megakaryocytic human erythroleukemia cells revealed that RUNX1 regulates RAB31 via binding to its promoter. We investigated RUNX1 and RAB31 roles in endosomal dynamics using immunofluorescence staining for markers of early endosomes (EEs; early endosomal autoantigen 1) and late endosomes (CD63)/multivesicular bodies. Downregulation of RUNX1 or RAB31 (by small interfering RNA or CRISPR/Cas9) showed a striking enlargement of EEs, partially reversed by RAB31 reconstitution. This EE defect was observed in MKs differentiated from a patient-derived induced pluripotent stem cell line (RHD-iMKs). Studies using immunofluorescence staining showed that trafficking of 3 proteins with distinct roles (von Willebrand factor [VWF], a protein trafficked to α-granules; epidermal growth factor receptor; and mannose-6-phosphate) was impaired at the level of EE on downregulation of RAB31 or RUNX1. There was loss of plasma membrane VWF in RUNX1- and RAB31-deficient megakaryocytic human erythroleukemia cells and RHD-iMKs. These studies provide evidence that RAB31 is downregulated in RHD and regulates megakaryocytic vesicle trafficking of 3 major proteins with diverse biological roles. EE defect and impaired vesicle trafficking is a potential mechanism for the α-granule defects observed in RUNX1 deficiency.


Assuntos
Leucemia Eritroblástica Aguda , Megacariócitos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Receptores ErbB/metabolismo , Humanos , Megacariócitos/metabolismo , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Fator de von Willebrand/metabolismo
18.
Clin Cancer Res ; 28(17): 3804-3813, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35705524

RESUMO

PURPOSE: To study the biology and identify markers of severe cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) in children after chimeric antigen receptor T-cell (CAR T) treatment. EXPERIMENTAL DESIGN: We used comprehensive proteomic profiling to measure over 1,400 serum proteins at multiple serial timepoints in a cohort of patients with B-cell acute lymphoblastic leukemia treated with the CD19-targeted CAR T CTL019 on two clinical trials. RESULTS: We identified fms-like tyrosine kinase 3 (FLT3) and mast cell immunoglobulin-like receptor 1 (MILR1) as preinfusion predictive biomarkers of severe CRS. We demonstrated that CRS is an IFNγ-driven process with a protein signature overlapping with hemophagocytic lymphohistiocytosis (HLH). We identified IL18 as a potentially targetable cytokine associated with the development of ICANS. CONCLUSIONS: We identified preinfusion biomarkers that can be used to predict severe CRS with a sensitivity, specificity, and accuracy superior to the current gold standard of disease burden. We demonstrated the fundamental role of the IFNγ pathway in driving CRS, suggesting CRS and carHLH are overlapping rather than distinct phenomena, an observation with important treatment implications. We identified IL18 as a possible targetable cytokine in ICANS, providing rationale for IL18 blocking therapies to be translated into clinical trials in ICANS.


Assuntos
Síndromes Neurotóxicas , Receptores de Antígenos Quiméricos , Biomarcadores , Criança , Síndrome da Liberação de Citocina/etiologia , Citocinas/metabolismo , Humanos , Imunoterapia Adotiva , Interleucina-18 , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/etiologia , Proteoma , Proteômica
20.
Front Vet Sci ; 9: 862308, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35498738

RESUMO

Objective: Septic peritonitis is associated with significant morbidity and mortality. As a potential therapeutic agent in the treatment of sepsis, 2-O, 3-O desulfated heparin (ODSH) reduces histones and platelet factor 4 (PF4) in mouse sepsis models. This pilot clinical trial evaluated the safety and effect of ODSH in client-owned dogs with septic peritonitis. Interventions: In an IACUC-approved, open-label, prospective, dose-escalation clinical trial in 6 dogs with spontaneous septic peritonitis, ODSH administration was initiated following surgical explore to achieve source control. Acute patient physiology and laboratory evaluation (APPLEfast and APPLEfull) scores on admission, source of septic peritonitis, requirement for vasopressors, the administration of blood products, and survival to discharge were recorded. Platelet count, cell free DNA (cfDNA) concentration, and platelet factor 4 (PF4) concentrations were measured at the time of each ODSH dosage. A dose of ODSH was administered every 8 hs for a total of 4 doses (maximum total dosage 75 mg/kg) based on a pre-determined escalation protocol. Patients were monitored in the ICU following administration for evidence of clinical hemorrhage. Main Results: The mean APPLEfast and APPLEfull scores on admission were 22 +/- 6 and 32 +/-10, respectively. Four dogs received 4 total dosages of ODSH and 2 dogs received 3 total dosages of ODSH intravenously. The mean total dosage of ODSH administered during the study period was 48.3 +/- 21.6 mg/kg. No dog required dose de-escalation or had any evidence of bleeding. Four dogs survived to discharge. Conclusions: No adverse effects of ODSH administration were documented in dogs with septic peritonitis. A randomized controlled trial is necessary to evaluate ODSH as a novel therapeutic in the treatment of septic peritonitis.

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