| 3101. |
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| 3102. |
- Semple, John W, et al.
(författare)
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Transfusion-associated circulatory overload and transfusion-related acute lung injury.
- 2019
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 133:17, s. 1840-1853
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Forskningsöversikt (refereegranskat)abstract
- Transfusion-associated circulatory overload (TACO) and Transfusion-related acute lung injury (TRALI) are syndromes of acute respiratory distress which occur within 6 hours of blood transfusion. TACO and TRALI are the leading causes of transfusion-related fatalities and specific therapies are unavailable. Diagnostically, it remains very challenging to distinguish TACO and TRALI from underlying causes of lung injury and/or fluid overload as well as from each other. TACO is characterized by pulmonary hydrostatic (cardiogenic) edema, while TRALI presents as pulmonary permeability edema (noncardiogenic). The pathophysiology of both syndromes is complex and incompletely understood. A 2-hit model is generally assumed to underlie TACO and TRALI disease pathology where the first hit represents the clinical condition of the patient and the second hit is conveyed by the transfusion product. In TACO, cardiac- or renal impairment and positive fluid balance appear first hits while suboptimal fluid management or other components in the transfused product may enable the second hit. Remarkably, other factors beyond volume play a role in TACO. In TRALI, the first hit can, for example, be represented by inflammation while the second hit is assumed to be caused by anti-leukocyte antibodies or biological response modifiers (e.g. lipids). In this review, we provide an up-to-date overview of TACO and TRALI regarding clinical definitions, diagnostic strategies, pathophysiological mechanisms and potential therapies. More research is required to better understand the TACO and TRALI pathophysiology and more biomarker studies are warranted. Collectively, this may result in improved diagnostics and development of therapeutic approaches for these life-threating transfusion reactions.
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| 3103. |
- Sen, Taha, et al.
(författare)
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Decreased PGC1beta expression results in disrupted human erythroid differentiation, impaired hemoglobinization and cell cycle exit
- 2021
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 11:1, s. 1-14
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Tidskriftsartikel (refereegranskat)abstract
- Production of red blood cells relies on proper mitochondrial function, both for their increased energy demands during differentiation and for proper heme and iron homeostasis. Mutations in genes regulating mitochondrial function have been reported in patients with anemia, yet their pathophysiological role often remains unclear. PGC1β is a critical coactivator of mitochondrial biogenesis, with increased expression during terminal erythroid differentiation. The role of PGC1β has however mainly been studied in skeletal muscle, adipose and hepatic tissues, and its function in erythropoiesis remains largely unknown. Here we show that perturbed PGC1β expression in human hematopoietic stem/progenitor cells from both bone marrow and cord blood results in impaired formation of early erythroid progenitors and delayed terminal erythroid differentiation in vitro, with accumulations of polychromatic erythroblasts, similar to MDS-related refractory anemia. Reduced levels of PGC1β resulted in deregulated expression of iron, heme and globin related genes in polychromatic erythroblasts, and reduced hemoglobin content in the more mature bone marrow derived reticulocytes. Furthermore, PGC1β knock-down resulted in disturbed cell cycle exit with accumulation of erythroblasts in S-phase and enhanced expression of G1-S regulating genes, with smaller reticulocytes as a result. Taken together, we demonstrate that PGC1β is directly involved in production of hemoglobin and regulation of G1-S transition and is ultimately required for proper terminal erythroid differentiation.
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| 3104. |
- Sen, Taha
(författare)
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Elucidating regulators of red blood cell development in health and disease
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Red blood cells are are plentiful, flexible and essential. They are the most abundant cell in our body and their mainobject is to carry oxygen, which is essential for cellular respiration. The formation of red blood cells is callederythropoiesis. Erythropoiesis is intimately coupled to cell division and mitochondrial function. Aberrations in thesetwo processes are often associated with red blood cell disorders, which result in anemia. Anemia is characterizedby the lack of red blood cells and/or reduced hemoglobin concentrations resulting in reduced oxygen transport tothe tissue and inevitable to reduced quality of life and increased mortality. My aim in this thesis has been todeepen our understanding of how erythropoiesis is regulated in health and diseaseIn the first paper we demonstrated that anemia caused by pRb deficiency was due to disrupted differentiation withunderlying impairment to mitochondrial function at the orthochromatic erythroblast stage. The MDS-like phenotypeof pRb deficient mice could be rescued by enhanced PPAR pathway signaling, an important signaling axis inmitochondrial biogenesis, in vivo either genetically or therapeutically.In the second paper we translated our findings in the mouse to a human setting by inhibiting PPAR signaling. Wedemonstrated that perturbed PPAR signaling in human hematopoietic stem/progenitor cells from both bonemarrow and cord blood results in impaired formation of early erythroid progenitors and delayed terminal erythroiddifferentiation in vitro. We showed that PPAR signaling is important for iron, heme and globin homeostasis.Furthermore we demonstrated that PPAR signaling affects cell cycle exit indicating that there is a mutualregulation between cell cycle progression and mitochondrial function during terminal erythropoiesis.In the third paper we demonstrated that Ypel4, which is highly expressed in orthochromatic erythroblasts, isimportant for the integrity of red blood cell membrane. Ypel4 null erythroblast had reduced deformability and werecleared at an increased rate. The phenotype resembled defects normally observed in human hereditarymembrane disorders.Overall the papers included in this thesis highlight mechanisms and genes important for terminal erythropoiesisspecifically in the orthochromatic erythroblast. We further described disease associated with the differentperturbations to erythropoiesis. The work presented
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| 3105. |
- Sen, Taha, et al.
(författare)
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Enhancing mitochondrial function in vivo rescues MDS-like anemia induced by pRb deficiency
- 2020
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Ingår i: Experimental Hematology. - : Elsevier BV. - 0301-472X. ; 88, s. 28-41
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Tidskriftsartikel (refereegranskat)abstract
- Erythropoiesis is intimately coupled to cell division, and deletion of the cell cycle regulator retinoblastoma protein (pRb) causes anemia in mice. Erythroid-specific deletion of pRb has been found to result in inefficient erythropoiesis because of deregulated coordination of cell cycle exit and mitochondrial biogenesis. However, the pathophysiology remains to be fully described, and further characterization of the link between cell cycle regulation and mitochondrial function is needed. To this end we further assessed conditional erythroid-specific deletion of pRb. This resulted in macrocytic anemia, despite elevated levels of erythropoietin (Epo), and an accumulation of erythroid progenitors in the bone marrow, a phenotype strongly resembling refractory anemia associated with myelodysplastic syndromes (MDS). Using high-fractionation fluorescence-activated cell sorting analysis for improved phenotypic characterization, we illustrate that erythroid differentiation was disrupted at the orthochromatic stage. Transcriptional profiling of sequential purified populations revealed failure to upregulate genes critical for mitochondrial function such as Pgc1β, Alas2, and Abcb7 specifically at the block, together with disturbed heme production and iron transport. Notably, deregulated ABCB7 causes ring sideroblastic anemia in MDS patients, and the mitochondrial co-activator PGC1β is heterozygously lost in del5q MDS. Importantly, the anemia could be rescued through enhanced PPAR signaling in vivo via either overexpression of Pgc1β or bezafibrate administration. In conclusion, lack of pRb results in MDS-like anemia with disrupted differentiation and impaired mitochondrial function at the orthochromatic erythroblast stage. Our findings reveal for the first time a role for pRb in heme and iron regulation, and indicate that pRb-induced anemia can be rescued in vivo through therapeutic enhancement of PPAR signaling.
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| 3106. |
- Sevov, Marie, et al.
(författare)
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Longitudinal study of RNA-based prognostic markers in chronic lymphocytic leukemia reveals LPL as the most stable
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Several genes display differential expression in prognostic subsets in chronic lymphocytic leukemia (CLL), including LPL, TCL1, ZAP70 and MCL1. CLL patients commonly have an indolent course with low stage disease and long survival, and in this study we aimed to investigate the stability of RNA-based prognostic markers in such an indolent cohort over time. mRNA expression of LPL, TCL1, ZAP70 and MCL1 was measured in sequential unsorted samples obtained from 96 CLL patients at both diagnosis and a median follow-up of seven years. LPL was the only RNA-based marker that did not demonstrate any significant changes in expression in diagnostic vs. follow-up samples. Furthermore, an 82% concordance between both time-points was observed when grouping cases based on high or low expression. LPL expression was not affected by treatment and in addition, LPL expression in follow-up samples could predict overall survival. In contrast, TCL1 expression was found to increase at follow-up, especially in cases displaying low expression at diagnosis. As TCL1 promotes cell survival this increase could possibly be of importance for progression of the disease. Both ZAP70 and MCL1 mRNA expression were found to vary significantly during the disease course. In summary, using unsorted CLL samples, we have demonstrated that LPL is superior to other RNA-based markers based on stability over time. These findings fully endorse the use of LPL analysis at any time point of the disease.
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| 3107. |
- Sevov, Marie
(författare)
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RNA-based Prognostic Markers in Chronic Lymphocytic Leukemia
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Chronic lymphocytic leukemia (CLL) is a heterogeneous disease where a significant proportion of patients will develop an aggressive disease. Today, the mutational status of the immunoglobulin heavy variable (IGHV) genes is one of the strongest prognostic markers in CLL, where unmutated IGHV genes correlate with poor outcome. In addition, IGHV3-21 gene usage is associated with poor prognosis independent of mutational status. Recently, several genes were shown to be differently expressed between IGHV mutated and unmutated CLL and were suggested as prognostic markers. The aim of this thesis was to examine the applicability of these RNA-based prognostic markers in CLL. In papers I and II, the prognostic significance of LPL and TCL1A mRNA expression in CLL was investigated in 140 and 144 patients, respectively. High expression was found to be associated with inferior clinical outcome for both markers. However, CLL cases with mutated IGHV3-21 genes displayed low levels of LPL expression, indicating that LPL cannot identify this poor-risk patient group. In contrast, high TCL1A expression was detected in all IGHV3-21 cases. To elucidate the functionality of LPL in CLL, LPL lipase activity was measured in 33 cases. The lipase activity was found to be invariably low, implying an alternative function for LPL in CLL. In paper III, a comprehensive analysis of five RNA-based markers (LPL, TCL1A, ZAP70, CLLU1 and MCL1) was performed in 252 CLL patients. All RNA-based markers except MCL1 predicted clinical outcome, with LPL being the strongest. Moreover, LPL expression independently predicted overall survival when adjusted for established markers. All of the RNA-based markers added additional prognostic information to established markers, e.g. high LPL expression predicted an inferior outcome in patients with mutated IGHV genes or good-risk cytogenetics. For clinical application, over time stability of prognostic markers is crucial. In paper IV, the expression of LPL, TCL1A, ZAP70 and MCL1 was investigated in samples taken at diagnosis and at a follow-up of seven years in 104 CLL patients. LPL was found to be the most stable marker, displaying high correlation between the sequential samples, whereas ZAP70 and MCL1 varied significantly. TCL1A expression increased at follow-up, which may indicate disease progression as TCL1A promotes cell survival. In summary, this thesis highlights the applicability of RNA-based markers in CLL prognostication, both as single markers or in combination with established markers. In particular, LPL was shown to be the strongest RNA-based marker in terms of prognostic strength and stability.
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| 3108. |
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| 3109. |
- Shah, Anita, et al.
(författare)
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Direct comparison of two extended-half-life recombinant FVIII products : a randomized, crossover pharmacokinetic study in patients with severe hemophilia A
- 2019
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Ingår i: Annals of Hematology. - : Springer Science and Business Media LLC. - 0939-5555 .- 1432-0584. ; 98:9, s. 2035-2044
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Tidskriftsartikel (refereegranskat)abstract
- BAY 94-9027 is an extended-half-life, recombinant factor VIII (rFVIII) product conjugated with a 60-kDa branched polyethylene glycol (PEG) molecule indicated for use in previously treated patients (aged ≥ 12 years) with hemophilia A. This randomized, open-label, two-way crossover study compared the pharmacokinetics (PK) of BAY 94-9027 and rFVIII Fc fusion protein (rFVIIIFc) in patients with hemophilia A. Patients aged 18–65 years with FVIII < 1% and ≥ 150 exposure days to FVIII were randomized to receive intravenous single-dose BAY 94-9027 60 IU/kg followed by rFVIIIFc 60 IU/kg or vice versa, with ≥ 7-day wash-out between doses. FVIII activity was measured by one-stage assay. PK parameters, including area under the curve from time 0 to the last data point (AUClast, primary parameter), half-life, and clearance were calculated. Eighteen patients were randomized and treated. No adverse events were observed. In the analysis set excluding one outlier, geometric mean (coefficient of variation [%CV, 95% confidence interval {CI}]) AUClast was significantly higher for BAY 94-9027 versus rFVIIIFc (2940 [37.8, 2440–3550] IU h/dL versus 2360 [31.8, 2010–2770] IU h/dL, p = 0.0001). A population PK model was developed to simulate time to reach FVIII threshold levels; median time to 1 IU/dL was approximately 13 h longer for BAY 94-9027 versus rFVIIIFc after a single infusion of 60 IU/kg. In conclusion, BAY 94-9027 had a superior PK profile versus rFVIIIFc. ClinicalTrials.gov: NCT03364998.
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| 3110. |
- Shah, Kinjal, et al.
(författare)
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PLK1 as a cooperating partner for BCL2-mediated antiapoptotic program in leukemia
- 2023
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Ingår i: Blood Cancer Journal. - 2044-5385. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- The deregulation of BCL2 family proteins plays a crucial role in leukemia development. Therefore, pharmacological inhibition of this family of proteins is becoming a prevalent treatment method. However, due to the emergence of primary and acquired resistance, efficacy is compromised in clinical or preclinical settings. We developed a drug sensitivity prediction model utilizing a deep tabular learning algorithm for the assessment of venetoclax sensitivity in T-cell acute lymphoblastic leukemia (T-ALL) patient samples. Through analysis of predicted venetoclax-sensitive and resistant samples, PLK1 was identified as a cooperating partner for the BCL2-mediated antiapoptotic program. This finding was substantiated by additional data obtained through phosphoproteomics and high-throughput kinase screening. Concurrent treatment using venetoclax with PLK1-specific inhibitors and PLK1 knockdown demonstrated a greater therapeutic effect on T-ALL cell lines, patient-derived xenografts, and engrafted mice compared with using each treatment separately. Mechanistically, the attenuation of PLK1 enhanced BCL2 inhibitor sensitivity through upregulation of BCL2L13 and PMAIP1 expression. Collectively, these findings underscore the dependency of T-ALL on PLK1 and postulate a plausible regulatory mechanism. [Figure not available: see fulltext.]
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