Range Of Hematological Disorders Research Articles

In Silico Evaluation of Coding and Non-Coding nsSNPs in the Thrombopoietin Receptor (MPL) Proto-Oncogene: Assessing Their Influence on Protein Stability, Structure, and Function.

The thrombopoietin receptor (MPL) gene is a critical regulator of hematopoiesis, and any alterations in its structure or function can result in a range of hematological disorders. Non-synonymous single nucleotide polymorphisms (nsSNPs) in MPL have the potential to disrupt normal protein function, prompting our investigation into the most deleterious MPL SNPs and the associated structural changes affecting protein-protein interactions. We employed a comprehensive suite of bioinformatics tools, including PredictSNP, InterPro, ConSurf, I-Mutant2.0, MUpro, Musitedeep, Project HOPE, STRING, RegulomeDB, Mutpred2, CScape, and CScape Somatic, to analyze 635 nsSNPs within the MPL gene. Among the analyzed nsSNPs, PredictSNP identified 28 as significantly pathogenic, revealing three critical functional domains within MPL. Ten of these nsSNPs exhibited high conservation scores, indicating potential effects on protein structure and function, while 14 were found to compromise MPL protein stability. Although the most harmful nsSNPs did not directly impact post-translational modification sites, 13 had the capacity to substantially alter the protein's physicochemical properties. Some mutations posed a risk to vital protein-protein interactions crucial for hematological functions, and three non-coding region nsSNPs displayed significant regulatory potential with potential implications for hematopoiesis. Furthermore, 13 out of 21 nsSNPs evaluated were classified as high-risk pathogenic variants by Mutpred2. Notably, amino acid alterations such as C291S, T293N, D295G, and W435C, while impactful on protein stability and function, were deemed non-oncogenic "passenger" mutations. Our study underscores the substantial impact of missense nsSNPs on MPL protein structure and function. Given MPL's central role in hematopoiesis, these mutations can significantly disrupt hematological processes, potentially leading to a variety of disorders. The identified high-risk pathogenic nsSNPs may hold promise as potential biomarkers or therapeutic targets for hematological diseases. This research lays the foundation for future investigations into the MPL gene's role in the realm of hematological health and diseases.

Peripheral intravenous catheter failure—is it us or is it them?

Intravenous therapy for patients with a range of haematological disorders is an essential component of disease treatment. Although central venous access devices are preferred for irritant or vesicant intravenous therapies, the peripheral intravenous catheter (PIVC) has an important role, offering a simple, cost-effective way to deliver short-term, peripherally compatible treatments. Unfortunately, this important device is susceptible to failure, with more than half of all PIVCs in hospitalised patients developing complications such as occlusion, infiltration, phlebitis, dislodgement, and infections that result in device removal.

3095 – PATHOGENIC RUNX1 MUTATIONS CAUSE DIFFERENT MALIGNANCIES BY UNIQUELY DISRUPTING GENE REGULATION HUBS

RUNX1 is a master haematopoietic transcription factor with cell-type dependent functions and thus RUNX1 mutations are seen in a range of haematological disorders. To understand the molecular basis of how different types of RUNX1 mutations send hematopoietic precursors on the path to disease we generated ESCs expressing inducible human RUNX1 mutants. We studied the fusion proteins RUNX1-ETO and RUNX1-EVI1, the truncated RUNX1-R177X protein that consists of the DNA binding domain only and RUNX1-R174Q which has a point mutation in the DNA binding domain. These are all associated with haematological disorders, including MDS, FPD and AML. To examine the immediate effect of oncogene induction on the blood progenitor gene regulatory network, we differentiated transgenic ESCs towards blood progenitors, induced the oncogene and performed systems-wide analysis shortly after induction. All induced progenitors demonstrated disrupted colony forming capacity, in a disease-driver specific fashion. RNA-seq and ATAC-seq analyses of induced cells showed mutation specific changes in gene expression and the chromatin landscape. The chromatin changes had unique motif patterns suggesting perturbed transcription factor interactions. The impact upon the binding of endogenous RUNX1 was varied – both RUNX1-ETO and RUNX1-EVI1 displaced RUNX1 from its binding sites, but induction of RUNX1-EVI1 also shifted RUNX1 binding to new sites. R174Q did not bind to the genome itself but reduced normal RUNX1 binding via decreased interaction with CBFβ as shown by proximity ligation assays. R177X caused only limited changes to RUNX1. Our data show that differential interactions of each RUNX1 mutant protein with the endogenous RUNX1 transcription factor hub cause specific epigenetic changes thus leading to the development of unique gene regulatory networks driving different types of malignancies.

Predicting CD4 T-Cell Reconstitution Following Pediatric Hematopoietic Stem Cell Transplantation.

Hematopoietic stem cell transplantation (HSCT) is an increasingly common treatment for children with a range of hematological disorders. Conditioning with cytotoxic chemotherapy and total body irradiation leaves patients severely immunocompromised. T‐cell reconstitution can take several years due to delayed restoration of thymic output. Understanding T‐cell reconstitution in children is complicated by normal immune system maturation, heterogeneous diagnoses, and sparse uneven sampling due to the long time spans involved. We describe here a mechanistic mathematical model for CD4 T‐cell immune reconstitution following pediatric transplantation. Including relevant biology and using mixed‐effects modeling allowed the factors affecting reconstitution to be identified. Bayesian predictions for the long‐term reconstitution trajectories of individual children were then obtained using early post‐transplant data. The model was developed using data from 288 children; its predictive ability validated on data from a further 75 children, with long‐term reconstitution predicted accurately in 81% of the patients.

Abstract 12: JAK2V617F drives Mcl-1 expression and sensitizes acute myeloid leukemia cells to dual inhibition of JAK2 and Bcl-XL

Abstract Constitutive activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) axis is fundamental to the molecular pathogenesis of a host of hematological disorders, including acute leukemias and myeloproliferative neoplasms (MPN). We demonstrate here that the major JAK2 mutation observed in these diseases (JAK2V617F) enforces Mcl-1 transcription via STAT3 and STAT5 signaling. Targeting this lesion with JAK inhibitor I (JAKi-I), attenuates STAT3 binding to the Mcl-1 promoter and suppresses Mcl-1 transcript and protein expression. The neutralization of Mcl-1 in JAK2V617F-harboring acute leukemia lines sensitizes them to apoptosis induced by the BH3-mimetic and Bcl-XL/Bcl-2 inhibitor, ABT-263. Moreover, simultaneously targeting JAK and Bcl-XL/-2 is synergistic in the presence of the JAK2V617F mutation. These findings suggest that JAK/Bcl-XL/-2 inhibitor combination therapy may have applicability in a range of hematological disorders characterized by activating JAK2 mutations. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 12. doi:10.1158/1538-7445.AM2011-12

Parvovirus B19 infection in children with a variety of hematological disorders

This study was carried out to detect Parvovirus B19 (PB19) DNA together with its antibodies in the sera of children with a range of hematological disorders to clarify the contribution of this infection to changes observed in hematological picture in those populations. This study included 85 pediatric patients with different hematological disorders. Twenty healthy subjects with matched age and sex were included as controls. Patients were classified into four groups; group I included 25 patients with hemolytic anemia in aplastic crisis, group II included 20 patients with hemolytic anemia without aplastic crisis, group III included 20 acute leukemia patients under chemotherapy, group IV included 20 patients with recently diagnosed acute leukemia. Virological study for PB19 included determination of specific IgG & IgM together with viral DNA by polymerase chain reaction (PCR).In all groups of patients with positive markers for PB19, there were statistically significant differences in the mean Hb concentration and RBC count (P < 0.001 for each), presence of neutropenia (P = 0.003) and lymphocytosis (P < 0.001) compared to controls. There was statistically significant difference in the prevalence of PB19 IgM, IgG and PCR among studied groups compared to control group. In group I and group II IgG had the highest positive rate (56 and 35%, respectively). In group III IgG also had a high positive rate (45%). However, in group IV IgM had the highest positive rate (50%) followed by PCR (45%) then IgG (40%).In conclusion, PB19 infection is detected in high rates among children with hematological disorders. PB19 must be suspected and screened for when there is anemia in those patients associated with neutropenia and lymphocytosis. In patients with acute leukaemia under chemotherapy who have unexpected anemia, neutropenia and lymphocytosis Parvovirus infection should be considered before a change of chemotherapy protocol. Screening of blood for PB19 may be helpful in understanding the epidemiology of infection with this virus. The direct detection of DNA by PCR in sera needs to be coupled with serology for a more reliable diagnosis of PB19 infections in these children.

An enhanced immunocytochemical method for staining bone marrow trephine sections.

AIMS: The detection of cellular antigens in fixed decalcified bone marrow trephine (BMT) sections depends on the method of processing, the nature of the antigen and antibody, antigen retrieval techniques,...

Serum Form of the Erythropoietin Receptor Identified by a Sequence-Specific Peptide Antibody

The present investigation was undertaken to search for soluble forms of the erythropoietin receptor in human serum using polyclonal antibody against an amino terminal peptide sequence in the extracellular domain. This sequence was located adjacent to the amino terminus at residues 25-38. When this antibody was used for Western blots of solubilized membranes from nucleated bone marrow cells, a protein consistent with native erythropoietin receptor was seen. Purified soluble ectodomain of the erythropoietin receptor displayed appropriate reactivity with this antibody. When sera from normal subjects and patients with a range of hematologic disorders were examined by Western blotting, a protein with a molecular mass of 34 Kd was detected in sera from patients with enhanced erythropoiesis including sickle cell anemia, thalassemia, and megaloblastic anemia. This protein was rarely detected in normal serum but appeared when normal subjects were treated with recombinant erythropoietin and disappeared after full treatment of patients with megaloblastic anemia due to vitamin B12 deficiency. The protein was not detected after myeloablation for bone marrow transplantation but appeared with marrow engraftment. Reactivity of this protein with the peptide antibody was competitively inhibited by the amino terminal peptide sequence. An additional 48 Kd protein was detected that showed minimal variation in intensity with differing degrees of erythropoietic activity. Detection of this protein could not be inhibited by the addition of synthetic peptide. Our findings indicate the presence of a soluble form of the erythropoietin receptor related to the extracellular domain that is highly correlated with enhanced erythropoiesis.

Serum form of the erythropoietin receptor identified by a sequence- specific peptide antibody [see comments

The present investigation was undertaken to search for soluble forms of the erythropoietin receptor in human serum using polyclonal antibody against an amino terminal peptide sequence in the extracellular domain. This sequence was located adjacent to the amino terminus at residues 25- 38. When this antibody was used for Western blots of solubilized membranes from nucleated bone marrow cells, a protein consistent with native erythropoietin receptor was seen. Purified soluble ectodomain of the erythropoietin receptor displayed appropriate reactivity with this antibody. When sera from normal subjects and patients with a range of hematologic disorders were examined by Western blotting, a protein with a molecular mass of 34 Kd was detected in sera from patients with enhanced erythropoiesis including sickle cell anemia, thalassemia, and megaloblastic anemia. This protein was rarely detected in normal serum but appeared when normal subjects were treated with recombinant erythropoietin and disappeared after full treatment of patients with megaloblastic anemia due to vitamin B12 deficiency. The protein was not detected after myeloablation for bone marrow transplantation but appeared with marrow engraftment. Reactivity of this protein with the peptide antibody was competitively inhibited by the amino terminal peptide sequence. An additional 48 Kd protein was detected that showed minimal variation in intensity with differing degrees of erythropoietic activity. Detection of this protein could not be inhibited by the addition of synthetic peptide. Our findings indicate the presence of a soluble form of the erythropoietin receptor related to the extracellular domain that is highly correlated with enhanced erythropoiesis.

Clinical significance of the del(20q) chromosome in hematologic disorders

Patients with hematologic neoplasias often have chromosomal aberrations in the cells of their bone marrow or unstimulated blood. One recurrent abnormality is a deletion of the long arm of chromosome 20, primarily described in polycythemia vera, but later seen in a range of hematologic disorders. We have studied 32 patients with del(20q) as the sole chromosomal aberration, investigating significance of this aberration for the clinical diagnoses, hematologic parameters, and prognoses within this patient group. According to our results, del(20q) is primarily associated with myeloid disorders, but it is not specific for any certain disease, nor does the proportion of cells with del(20q) correlate with prognosis.