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Haematologica Jul 2022Chronic myelomonocytic leukemia (CMML) is a myelodysplastic syndrome/myeloproliferative overlap neoplasm characterized by sustained peripheral blood monocytosis and an...
Chronic myelomonocytic leukemia (CMML) is a myelodysplastic syndrome/myeloproliferative overlap neoplasm characterized by sustained peripheral blood monocytosis and an inherent risk for transformation to acute myeloid leukemia (15-30% over 3-5 years). While CMML is morphologically classified into CMML-0, 1 and 2 based on peripheral blood and bone marrow promonocyte/blast counts, a more clinically relevant classification into dysplastic and proliferative subtypes, based on the presenting white blood cell count, is helpful in prognostication and therapeutics. CMML is a neoplasm associated with aging, occurring on the background of clonal hematopoiesis, with TET2 and SRSF2 mutations being early initiating events. The subsequent acquisitions of ASXL1, RUNX1, SF3B1 and DNMT3A mutations usually give rise to dysplastic CMML, while ASXL1, JAK2V617F and RAS pathway mutations give rise to proliferative CMML. Patients with proliferative CMML have a more aggressive course with higher rates of transformation to acute myeloid leukemia. Allogeneic stem cell transplant remains the only potential cure for CMML; however, given the advanced median age at presentation (73 years) and comorbidities, it is an option for only a few affected patients (10%). While DNA methyltransferase inhibitors are approved for the management of CMML, the overall response rates are 40-50%, with true complete remission rates of <20%. These agents seem to be particularly ineffective in proliferative CMML subtypes with RAS mutations, while the TET2mutant/ASXL1wildtype genotype seems to be the best predictor for responses. These agents epigenetically restore hematopoiesis in responding patients without altering mutational allele burdens and progression remains inevitable. Rationally derived personalized/targeted therapies with disease-modifying capabilities are much needed.
Topics: Humans; Leukemia, Myelomonocytic, Chronic; Leukemia, Myelomonocytic, Juvenile; Mutation; Myelodysplastic-Myeloproliferative Diseases; Prognosis
PubMed: 35236051
DOI: 10.3324/haematol.2021.279500 -
Journal of Extracellular Vesicles 2019Acetylcholinesterase (AChE) activity is found in abundance in reticulocytes and neurons and was developed as a marker of reticulocyte EVs in the 1970s. Easily, quickly,...
Acetylcholinesterase (AChE) activity is found in abundance in reticulocytes and neurons and was developed as a marker of reticulocyte EVs in the 1970s. Easily, quickly, and cheaply assayed, AChE activity has more recently been proposed as a generic marker for small extracellular vesicles (sEV) or exosomes, and as a negative marker of HIV-1 virions. To evaluate these proposed uses of AChE activity, we examined data from different EV and virus isolation methods using T-lymphocytic (H9, PM1 and Jurkat) and promonocytic (U937) cell lines grown in culture conditions that differed by serum content. When EVs were isolated by differential ultracentrifugation, no correlation between AChE activity and particle count was observed. AChE activity was detected in non-conditioned medium when serum was added, and most of this activity resided in soluble fractions and could not be pelleted by centrifugation. The serum-derived pelletable AChE protein was not completely eliminated from culture medium by overnight ultracentrifugation; however, a serum "extra-depletion" protocol, in which a portion of the supernatant was left undisturbed during harvesting, achieved near-complete depletion. In conditioned medium also, only small percentages of AChE activity could be pelleted together with particles. Furthermore, no consistent enrichment of AChE activity in sEV fractions was observed. Little if any AChE activity is produced by the cells we examined, and this activity was mainly present in non-vesicular structures, as shown by electron microscopy. Size-exclusion chromatography and iodixanol gradient separation showed that AChE activity overlaps only minimally with EV-enriched fractions. AChE activity likely betrays exposure to blood products and not EV abundance, echoing the MISEV 2014 and 2018 guidelines and other publications. Additional experiments may be merited to validate these results for other cell types and biological fluids other than blood.
PubMed: 31303981
DOI: 10.1080/20013078.2019.1628592 -
Annales de Biologie Clinique Oct 2019The discovery of a monocytosis is a frequent phenomenon, requiring confirmation by reading under a microscope by an experimented biologist, to overcome usual cytological... (Review)
Review
The discovery of a monocytosis is a frequent phenomenon, requiring confirmation by reading under a microscope by an experimented biologist, to overcome usual cytological traps such as the presence of hairy cells, promonocytes or monoblasts. In the vast majority of cases the secondary origin is very easily found by the context and/or the presence of a biological inflammatory syndrome. More rarely the diagnosis is directed towards an eosinophilic pathology or an acute leukemia. In other cases, CMML, MPN or MDS with monocytosis may be highlighted. In the absence of any pathognomonic element and the presence of "borderline" forms the differential diagnosis between these 3 entities is not always straightforward, requiring, according to WHO, molecular investigations and elimination of any reactive cause of monocytosis. Although histological, immunohistochemical and phenotypic flow cytometric studies are not currently recommended by WHO, these investigations could be of interest in the evaluation of difficult cases.
Topics: Adult; Age of Onset; Algorithms; Clinical Laboratory Techniques; Diagnosis, Differential; Humans; Leukocyte Count; Monocytes; Myelodysplastic Syndromes
PubMed: 31486402
DOI: 10.1684/abc.2019.1475 -
Journal of Extracellular Vesicles Apr 2021We compared four orthogonal technologies for sizing, counting, and phenotyping of extracellular vesicles (EVs) and synthetic particles. The platforms were:...
We compared four orthogonal technologies for sizing, counting, and phenotyping of extracellular vesicles (EVs) and synthetic particles. The platforms were: single-particle interferometric reflectance imaging sensing (SP-IRIS) with fluorescence, nanoparticle tracking analysis (NTA) with fluorescence, microfluidic resistive pulse sensing (MRPS), and nanoflow cytometry measurement (NFCM). EVs from the human T lymphocyte line H9 (high CD81, low CD63) and the promonocytic line U937 (low CD81, high CD63) were separated from culture conditioned medium (CCM) by differential ultracentrifugation (dUC) or a combination of ultrafiltration (UF) and size exclusion chromatography (SEC) and characterized by transmission electron microscopy (TEM) and Western blot (WB). Mixtures of synthetic particles (silica and polystyrene spheres) with known sizes and/or concentrations were also tested. MRPS and NFCM returned similar particle counts, while NTA detected counts approximately one order of magnitude lower for EVs, but not for synthetic particles. SP-IRIS events could not be used to estimate particle concentrations. For sizing, SP-IRIS, MRPS, and NFCM returned similar size profiles, with smaller sizes predominating (per power law distribution), but with sensitivity typically dropping off below diameters of 60 nm. NTA detected a population of particles with a mode diameter greater than 100 nm. Additionally, SP-IRIS, MRPS, and NFCM were able to identify at least three of four distinct size populations in a mixture of silica or polystyrene nanoparticles. Finally, for tetraspanin phenotyping, the SP-IRIS platform in fluorescence mode was able to detect at least two markers on the same particle, while NFCM detected either CD81 or CD63. Based on the results of this study, we can draw conclusions about existing single-particle analysis capabilities that may be useful for EV biomarker development and mechanistic studies.
Topics: Biomarkers; Cell Line; Chromatography, Gel; Extracellular Vesicles; Humans; Microfluidics; Microscopy, Electron, Transmission; Nanoparticles; Particle Size; Polystyrenes; Single Molecule Imaging; Ultracentrifugation; Ultrafiltration
PubMed: 33850608
DOI: 10.1002/jev2.12079 -
Frontiers in Immunology 2022Kawasaki disease (KD) is an autoimmune-like vasculitis of childhood involving the coronary arteries. Macrophages require scavenger receptors such as CD36 to effectively...
Kawasaki disease (KD) is an autoimmune-like vasculitis of childhood involving the coronary arteries. Macrophages require scavenger receptors such as CD36 to effectively clear cellular debris and induce self-tolerance. In this study, we hypothesized that CD36 plays an important role in the immunopathogenesis of KD, by aiding in the clearance of plasma mitochondrial DNA, and by amplifying the immune response by activating the inflammasome pathway AIM2. Fifty-two healthy controls, 52 febrile controls, and 102 KD patients were recruited for RT-PCR of target mRNA expression and plasma mitochondrial DNA. Blood samples were obtained 24 hours prior and 21 days after the administration of intravenous immunoglobulin (IVIG) therapy. Patients with acute KD had higher plasma levels of cell-free mitochondrial DNA (ND1, ND4, and COX1), and higher mRNA expressions of CD36 and AIM2 when compared to both healthy and febrile controls. A greater decrease in both CD36 and AIM2 mRNA expression after IVIG therapy was associated with the development of coronary artery lesions. Coronary artery lesions were associated with a larger decrease of CD36 expression following IVIG therapy, which may indicate that prolonged expression of the scavenger receptor may have a protective effect against the development of coronary artery lesions in KD.
Topics: Adolescent; CD36 Antigens; Child; Child, Preschool; Coronary Artery Disease; Coronary Vessels; Female; Gene Expression Profiling; Humans; Infant; Infant, Newborn; Leukocyte Count; Male; Mucocutaneous Lymph Node Syndrome; U937 Cells
PubMed: 35154107
DOI: 10.3389/fimmu.2022.790095 -
Frontiers in Bioinformatics 2022Osteoclasts are multinucleated cells that exclusively resorb bone matrix proteins and minerals on the bone surface. They differentiate from monocyte/macrophage-lineage...
Osteoclasts are multinucleated cells that exclusively resorb bone matrix proteins and minerals on the bone surface. They differentiate from monocyte/macrophage-lineage cells in the presence of osteoclastogenic cytokines such as the receptor activator of nuclear factor-κB ligand (RANKL) and are stained positive for tartrate-resistant acid phosphatase (TRAP). In vitro, osteoclast formation assays are commonly used to assess the capacity of osteoclast precursor cells for differentiating into osteoclasts wherein the number of TRAP-positive multinucleated cells are counted as osteoclasts. Osteoclasts are manually identified on cell culture dishes by human eyes, which is a labor-intensive process. Moreover, the manual procedure is not objective and result in lack of reproducibility. To accelerate the process and reduce the workload for counting the number of osteoclasts, we developed OC_Finder, a fully automated system for identifying osteoclasts in microscopic images. OC_Finder consists of cell image segmentation with a watershed algorithm and cell classification using deep learning. OC_Finder detected osteoclasts differentiated from wild-type and precursor cells at a 99.4% accuracy for segmentation and at a 98.1% accuracy for classification. The number of osteoclasts classified by OC_Finder was at the same accuracy level with manual counting by a human expert. OC_Finder also showed consistent performance on additional datasets collected with different microscopes with different settings by a different operator. Together, successful development of OC_Finder suggests that deep learning is a useful tool to perform prompt and accurate unbiased classification and detection of specific cell types in microscopic images.
PubMed: 35474753
DOI: 10.3389/fbinf.2022.819570 -
Annals of Medicine and Surgery (2012) Feb 2023Chronic myelomonocytic leukemia (CMML) is a rare disease of clonal hematopoietic stem cells with an inherent risk of leukemic transformation, seen in an elderly male.
UNLABELLED
Chronic myelomonocytic leukemia (CMML) is a rare disease of clonal hematopoietic stem cells with an inherent risk of leukemic transformation, seen in an elderly male.
CASE PRESENTATION
Herein, the authors report a case of CMML in a 72-year-old male who presented with fever and abdominal pain for 2 days with a history of easy fatigability. Examination revealed pallor and palpable supraclavicular nodes. Investigations showed leukocytosis with a monocyte count of 22% of white blood cell count, 17% blast cells in bone marrow aspiration, increased blast/promonocytes, and positive markers in immunophenotyping. The patient is planned for injection of azacitidine, 7 days cycle for a total of six cycles.
CLINICAL DISCUSSION
CMML is classified as overlapping myelodysplastic/myeloproliferative neoplasms. It can be diagnosed based on a peripheral blood smear, bone marrow aspiration and biopsy, chromosomal analysis, and genetic tests. The commonly used treatment options are hypomethylating agents like azacitidine and decitabine, allogeneic hematopoietic stem cell transplant, and cytoreductive agents like hydroxyurea.
CONCLUSION
Despite various treatment options, the treatment is still unsatisfactory, demanding standard management strategies.
PubMed: 36845813
DOI: 10.1097/MS9.0000000000000198 -
Iranian Journal of Allergy, Asthma, and... Dec 2020The T-cell immunoglobulin and mucin-3 (TIM-3)/galectin-9 (Gal-9) autocrine loop is an indispensable signaling in acute myeloid leukemia (AML) cells, which induces their...
Oridonin Could Inhibit Inflammation and T-cell Immunoglobulin and Mucin-3/Galectin-9 (TIM-3/Gal-9) Autocrine Loop in the Acute Myeloid Leukemia Cell Line (U937) as Compared to Doxorubicin.
The T-cell immunoglobulin and mucin-3 (TIM-3)/galectin-9 (Gal-9) autocrine loop is an indispensable signaling in acute myeloid leukemia (AML) cells, which induces their self-renewal through activation of nuclear factor-kappa b (NF-kB) and β-catenin pathways. In this study, we evaluated the effects of oridonin and doxorubicin on the TIM-3/Gal-9 autocrine loop. We also evaluated oridonin anti-inflammatory and anti-cancer properties on U937 cells, as an AML cell line in comparison to doxorubicin as a common anthracycline drug for AML treatment. Cell counting kit-8 (CCK-8) was applied to evaluate the cytotoxicity of oridonin and doxorubicin on U937 cells and also to determine the impact of galectin-9 (Gal-9) on their proliferation. The effects of oridonin and doxorubicin on Gal-9, TIM-3, and interleukin-1β (IL-1β) gene expression were determined by real-time polymerase chain reaction (RT-PCR). The Gal-9 secretion level was measured by enzyme-linked immunosorbent assay (ELISA) and activation of NF-kB pathway was assessed by western blotting. In a dose-dependent manner, oridonin and doxorubicin were capable to eradicate U937 cells while Gal-9 expanded them. Following the treatment of U937 cells with oridonin, the expression of Gal-9, TIM-3, and IL-1β genes was down-regulated, and the Gal-9 secretion and NF-kB phosphorylation were diminished, whereas doxorubicin increased all of these factors. Doxorubicin is a common treatment agent in AML, but it may induce inflammation and up-regulate the TIM3/Gal-9 autocrine loop, consequently can enhance the possibility of disease relapse. Meanwhile, oridonin is capable to inhibit the essential signaling pathways in AML cells and reduce the inflammation and expansion of tumor cells and postpone AML recurrence.
Topics: Cell Line, Tumor; Diterpenes, Kaurane; Doxorubicin; Galectins; Hepatitis A Virus Cellular Receptor 2; Humans; Immunoglobulins; Inflammation; Leukemia, Myeloid, Acute; NF-kappa B; Signal Transduction; T-Lymphocytes; U937 Cells
PubMed: 33463129
DOI: 10.18502/ijaai.v19i6.4929 -
BMC Cancer Nov 2021Despite of the frequently reported Dnmt3a abormality in classical myeloproliferative neoplasms (cMPNs) patients, few research explores how the Dnmt3a is regulated by...
BACKGROUND
Despite of the frequently reported Dnmt3a abormality in classical myeloproliferative neoplasms (cMPNs) patients, few research explores how the Dnmt3a is regulated by Jak2 mutation. In this study, we have investigated how the Dnmt3a is regulated by Jak2 mutation and its effects on downstream signaling pathways in cMPNs.
METHODS
Specimens of Jak2 positive cMPN patients and normal controls were collected. Murine BaF3 cell line was used to construct cell models. Dual-Glo luciferase assays and chromatin immunoprecipitation (ChIP)-qPCR were performed to detect the impact of Stat5a on transcription activity of Dnmt3a. Soft agar colony formation assay and cell counting assay were performed to detect cell proliferation. BrdU staining and flow cytometry were used to investigate cell cycle distribution. Western blotting and quantitative reverse-transcription PCR (qPCR) were performed to detect the expression levels of genes.
RESULTS
Firstly, the results of western blotting and qPCR revealed that compared with the control samples, Dnmt3a is downregulated in Jak2 positive samples. Then we explored the mechanism behind it and found that Dnmt3a is a downstream target of Stat5a, the transcription and translation of Dnmt3a is suppressed by the binding of aberrantly activated Stat5a with Dnmt3a promoter in Jak2 positive samples. We further revealed the region approximately 800 bp upstream of the first exon of the Dnmt3a promoter, which includes a gamma-activated sequence (GAS) motif of Stat5a, is the specific site that Stat5a binds to. Soft agar colony formation assay, cell counting assay, and BrdU staining and flow cytometry assay found that Dnmt3a in Jak2-BaF3 cells significantly affected the cell proliferation capacity and cell cycle distribution by suppressing Cdkn1a via miR-17-5p/Cdkn1a axis and mediated G0/G1 arrest.
CONCLUSIONS
Transcription and translation of Dnmt3a is downregulated by the binding of Stat5a with Dnmt3a promoter in Jak2 cells. The GAS motif at promoter of Dnmt3a is the exact site where the Stat5a binds to. Dnmt3a conducted G0/G1 arrest through regulating miR-17-5p/Cdkn1a axis. The axis of Stat5a/Dnmt3a/miR-17-5p/Cdkn1a potentially provides a treatment target for cMPNs.
Topics: Aminopyridines; Animals; Binding Sites; Blotting, Western; Case-Control Studies; Cell Count; Cell Line; Cell Line, Tumor; Cell Proliferation; Cyclin-Dependent Kinase Inhibitor p21; DNA Methyltransferase 3A; Down-Regulation; Exons; G1 Phase Cell Cycle Checkpoints; Humans; Imidazoles; Janus Kinase 2; K562 Cells; Mice; MicroRNAs; Monocytes; Mutation; Myeloproliferative Disorders; Promoter Regions, Genetic; Pyrazoles; Pyridazines; STAT5 Transcription Factor; Signal Transduction; Transcription, Genetic; Tumor Stem Cell Assay; Tumor Suppressor Proteins; U937 Cells
PubMed: 34773997
DOI: 10.1186/s12885-021-08915-0 -
Journal of Immunology Research 2021We recently showed that both nontypeable (NTHi) and its surface plasminogen- (Plg-) binding proteins interact with lipoprotein(a) (Lp(a)) in a lysine-dependent manner....
We recently showed that both nontypeable (NTHi) and its surface plasminogen- (Plg-) binding proteins interact with lipoprotein(a) (Lp(a)) in a lysine-dependent manner. Because Lp(a) can be taken up by macrophages, we postulated that it serves as an opsonin to enhance phagocytosis of NTHi by macrophages. Based on colony-forming unit (CFU) counts, Lp(a) was found to increase U937 macrophage-mediated phagocytosis of NTHi49247 and NTHi49766 by 34% and 43%, respectively, after 120 min. In contrast, Lp(a) did not enhance phagocytosis of BL21 or JM109, which were unable to bind to Lp(a). As with U937 macrophages, Lp(a) was capable of increasing phagocytosis of NTHi49247 by peripheral blood mononuclear cell-derived macrophages. Opsonic phagocytosis by Lp(a) was inhibited by the addition of recombinant kringle IV type 10 (rKIV), a lysine-binding competitor; moreover, Lp(a) did not increase phagocytosis of NTHi by U937 macrophages that were pretreated with a monoclonal antibody against the scavenger receptor CD36. Taken together, our observation suggests that Lp(a) might serve as a lysine-binding opsonin to assist macrophages in rapid recognition and phagocytosis of NTHi.
Topics: CD36 Antigens; Cell Line; Cell Line, Tumor; Escherichia coli; Haemophilus Infections; Haemophilus influenzae; Humans; Leukocytes, Mononuclear; Lipoprotein(a); Macrophages; Opsonin Proteins; Phagocytosis; U937 Cells
PubMed: 34765679
DOI: 10.1155/2021/2185568