To investigate the morphological changes of megakaryocytes with nuclear extrusion and nucleocytoplasmic separation, the morphological characteristics of megakaryocytes in peripheral blood films, bone marrow smears, and bone marrow biopsies from 4 newly diagnosed patients with primary myelofibrosis (PMF), myelodysplastic syndrome (MDS), myeloblastic leukemia with maturation (M(2)) and erythroleukemia (M(6)) were studied by using light microscope. The results showed that many kinds of dysmegakaryocytes were observed in bone marrow smears of 4 cases, while in case A (PMF) and case D (M(6)) micromegakaryocytes were ripped apart; in case B (MDS) and case C (M(2)) megakaryocytes were accompanied by nuclear extrusion or nucleocytoplasmic separation, and their bodies were large or giant, the part of nucleus separated from their body and little cytoplasm remained as micromegakaryocytes. The nucleocytoplasmic separation could be displayed by immunocytochemistry stain. It is concluded that the phenomenon of nuclear extrusion and nucleocytoplasmic separation in megakaryocytes suggested the process that dispersed multinuclear releasing towards surround or even totally left the cell body during the megakaryocyte maturation. It also showed that the micromegakaryocytes may be the result of nucleocytoplasmic separation or splittings from multi-separated nucleus.
Aged ; Bone Marrow Cells ; pathology ; Cell Nucleus ; pathology ; Cytoplasm ; pathology ; Female ; Hematologic Diseases ; blood ; Humans ; Male ; Megakaryocytes ; pathology ; Middle Aged

Actinin/genetics* ; Anemia ; Blood Platelets/pathology* ; Female ; Humans ; Male ; Megakaryocytes ; Mutation, Missense ; Pedigree ; Thrombocytopenia/genetics*

The study was aimed to observe morphological characteristics and hematopoiesis function of bone marrow megakaryocyte in children patients with myelodysplastic syndrome (MDS), and analyse the cause and mechanism of thrombocytopenia. CD41 McAb immunohistochemical technique was used to detect micromegakaryocytes of bone marrow smear. Plasma clot culture and CD41 McAb immunohistochemical technique were used for the MK-colony forming assay. The colony formations of CFU-MK and BFU-MK were measured. The results showed that there was no significant difference of CFU-MK colony formation rate between groups of MDS and control. But, in 62.5% of children patients the colony formation rate of CFU-MK decreased, in 25% increased, and in 12.5% was normal while BFU-MK formation rate decreased in MDS group significantly. The number of micromegakaryocyte and the positive rate of type I lymphoid micromegakaryocyte were significantly higher than those of the control group. In conclusion, there may be two kinds of megakaryocyte clones in bone marrow of children patients with MDS. One is supposed to be pathologic and potentially malignant micromegakaryocytes, the another may be the normal megakaryocytic precursors. The thrombocytopenia in MDS patients induced by increase of pathologic MK leads to abnormal development and maturation of MK in bone marrow.
Adolescent ; Bone Marrow Cells ; pathology ; Child ; Child, Preschool ; Female ; Hematopoiesis ; Humans ; Infant ; Male ; Megakaryocytes ; pathology ; Myelodysplastic Syndromes ; blood ; pathology

Light and electron microscopic studies of megakaryocytes in bone marrow from 14 cases of Korean epidemic hemorrhagic fever were made, together with clinical manifestations, laboratory findings, and changes in other marrow elements. The number of megakaryocytes increased in various degree from patient to patient, with a shift to the left of maturation gradation. Cytoplasms were markedly smaller but granularity was fairly good. The most constant finding was marked decrease or complete absence of platelet formation at the periphery of the cytoplasm. Ultrastructurally, there was a marked decrease of the cisternal system in the cytoplasm and lack of cleavage line. No virus particles or active degenerative process was noted. These changes of the megakaryocytes are similar to those reported in idiopathic thrombocytopenic purpura, indicating that megakaryocytic changes in Korean epidemic hemorrhagic fever are likely secondary to thrombocytopenia which was caused by other Mechanism.
Adult ; Aged ; Bone Marrow/pathology ; Female ; Hemorrhagic Fever with Renal Syndrome/pathology* ; Human ; Male ; Megakaryocytes/ultrastructure* ; Middle Age

In order to observe the proliferative and apoptotic situation of megakaryocytes in patients with myelodysplastic syndromes (MDS). CD41 immunoenzyme labeling (alkaline phosphatase anti-alkaline phosphatase APAAP)/DNA in situ end labelling (ISEL) double stained techniques was used onto plastic cold embedded bone marrow sections in 29 MDS patients to analyse the proliferative and apoptostic characterization of megakaryocytic line with 14 cases of iron deficient diseases (IDA) as control. The results showed that the mean CD41 positive cell number in MDS group was (26.23 +/- 8.18) /mm(2) with a count of (15.64 +/- 7.11) /mm(2) in control group (p < 0.05). The small-micro megakaryocytes in MDS is much higher than that in IDA group (P<0.01). There was a positive co-relation between total megakaryocytes and small-micro megakaryocytes count in MDS (r = 0.702, p<0.01). Some megakaryocytes distributed abnormally around trabecula and formed small or large clusters. Apoptotic megakaryocytes in MDS occupied 4.40% and 9.32% of all CD14 positive cells and all apoptotic cells respectively (p > 0.5 comparing with control). Apoptosis in megakargocytic line occurred only in small-micro megakaryocytes and showed positive co-relation to the number of micro-megakaryocytes. Some apoptotic cell with morphologic characters of megakaryocytes expressed no CD41. It is concluded that overproliferation of megakaryocytes exists in MDS. Apoptosis occurring in micro-megakaryocytes may be a kind of physiological response to abnormal megakaryopoicsis in MDS. No obvious increased apoptosis of megakaryocytes in MDS was found perhaps due to lack of surface antigens CD41 in some later stages of apoptotic cell.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Apoptosis ; Cell Division ; Child ; Female ; Humans ; Male ; Megakaryocytes ; pathology ; Middle Aged ; Myelodysplastic Syndromes ; pathology

OBJECTIVETo compare the morphologic features of bone marrow (BM) between the prefibrotic-early primary myelofibrosis (PMF) and essential thrombocythaemia (ET).

METHODSeven cases of prefibrotic-early PMF were selected and analyzed. Based on the diagnostic standard of prefibrotic-early PMF by WHO, BM aspirate smears, trephine biopsy sections and imprints of 156 uncertain ET cases conducted simultaneously were recruited into this study, the BM morphologic features between the prefibrotic-early PMF and ET groups were analyzed. The morphological difference in 22 cases of prefibrotic-early PMF and 27 ET were compared between the JAK2V617F mutation positive and negative groups.

RESULTSOf the 156 uncertain ET cases, it was reclassified 61 prefibrotic-early PMF (34 MF-0, 27 MF-1), 12 PMF and 83 ET. The platelet count and LDH level in MF-1 group were obviously higher than that of ET group (P < 0.05). The blast percentage of BM smear in MF-1 group was also higher than that of ET group (P < 0.05). As to BM section, cases with increased nucleated cells (granulocyte), compact megakaryocytic cluster, megakaryocyte near bone trabecula, cloud-like megakaryocyte, small bare nucleus of megakaryocyte and large ball-like megakaryocyte in MF-0 and MF-1 group were significantly higher than that of ET group (all P < 0.05), cases with megakaryocytic cluster of various size in MF-1 group were significantly higher than that of MF-0 and ET groups (P < 0.05). The JAK2V617F mutation rate in prefibrotic-early PMF and ET groups were 54.5% and 48.1%, respectively. Hb level in JAK2V617F mutation positive group was obviously higher than the negative group (P < 0.05), no special change with megakaryocytic morphology was found between the positive and negative groups.

CONCLUSIONMorphology of BM section, especially megakaryocytic morphologic characteristics are the main basis in distinguishing prefibrotic-early PMF from ET. The importance of morphologic index were megakaryocytic cluster with various size, cloud-like megakaryocyte, large ball-like megakaryocyte, increased nucleated cells (granulocyte), small bare nucleus, megakaryocyte near bone trabecula and compact megakaryocytic cluster in order. JAK2V617F mutation provides no specific effect on the megakaryocytic morphology.

Aged ; Bone Marrow ; pathology ; Bone Marrow Examination ; Female ; Humans ; Janus Kinase 2 ; genetics ; Male ; Megakaryocytes ; pathology ; Middle Aged ; Primary Myelofibrosis ; genetics ; pathology ; Thrombocythemia, Essential ; genetics ; pathology

OBJECTIVETo investigate the clinical significance of bone marrow morphological differences in the differential diagnosis of megaloblastic anemia (MM) and refractory anemia (R4).

METHODSA total of 60 anemia patients selected from our hospital between April 2004 and April 2015 were divided into MA group (30 cases) and RA group (30 cases) in accordance with their clinical diagnosis. Clinical manifestations, results of bone marrow morphology test, blood examination, peripheral blood smear, erythroid megaloblastic variability rate and nucleated red blood cell level in the 2 groups were compared and analyzed.

RESULTSIncidence of fever, hemorrhage, digestive reaction, splenomegaly and fatigue as well as hemoglobin level, platelets and white blood cell counts in patients of MA group were similar to those of RA group, there was no statistically significant difference between 2 groups (P>0.05). The percentages of dysplastic hematopoiesis in erythroid cells, granulocytic cells, magakaryoajtic cells, the PAS-positive rate and red blood cell distribution in the MA patients were obviously lower than those in the RA patients, while the erythroid megaloblastic variability rate (90%) in MA group was obviously higher than that in RA patients (10%) and with statistically significant difference (P<0.05). The percentage of immature red blood cells was similar between MA group (53.33%) and RA group (60.00%), without significant difference (P>0.05).

CONCLUSIONMost of clinical manifestations and peripheral blood smear results are consistent in MA patients and RA patients, bone marrow morphology detection in RA group should be focused on lymphocytoid micromegakaryocytes, while the erythroid megaloblastic cell body is the focus in MA group, PAS can be used as a diagnostic criteria.

Anemia, Megaloblastic ; diagnosis ; Anemia, Refractory ; diagnosis ; Bone Marrow ; pathology ; Diagnosis, Differential ; Erythrocyte Count ; Humans ; Leukocyte Count ; Megakaryocytes ; cytology

OBJECTIVEThrombocytopenic hemorrhage is one of the major appearance in pediatric hemorrhagic diseases, in which, idiopathic thrombocytopenic purpura (ITP) is the most common disease. Thrombocytopenia is the earliest phenomenon or the only one in certain phases of hemorrhagic diseases, such as ITP, aplastic anemia (AA) and myelodysplastic syndrome (MDS). By now, the pathogenesis of thrombocytopenia in different diseases has not been clearly determined. At present, it is very difficult to diagnose these diseases and estimate their prognosis with current clinical data. In this study, morphological characteristics and hematopoiesis function of bone marrow megakaryocyte in pediatric patients with ITP, AA and MDS were observed and the cause and mechanism of different thrombocytopenias were analyzed.

METHODSThere were 16 children with ITP, 17 with AA and 16 with MDS in this study. CD41 McAb immunohistochemical technique was used to detect micromegakaryocyte on bone marrow smears. Plasma clot culture and CD41 McAb immunohistochemical technique were used for the MK-colony forming assay. The colony formation rate of colony formation unit-megakaryocyte (CFU-MK) and burst formation unit-megakaryocyte (BFU-MK) were counted.

RESULTSThere was no statistical difference on the positive rates of micromegakaryocyte and type I lymphoid small micromegakaryocyte between groups of ITP and control. The number of micromegakaryocyte and the formation rates of CFU-MK in ITP group were significantly higher than those in control group. Among AA patients, the numbers of MK, micromegakaryocyte and the formation rates of CFU-MK, BFU-MK in vitro significantly decreased. There was no significant difference in the positive rate of micromegakaryocyte between groups of MDS and control, but the number of micromegakaryocyte and the positive rate of type I lymphoid micromegakaryocyte were significantly higher than those of control group. There was no statistical difference of the formation rate of CFU-MK between groups of MDS and control. But in 63% childhood patients, the formation rate of CFU-MK decreased, 25% increased,and 13% was normal; BFU-MK formation rate decreased significantly in MDS group.

CONCLUSIONOverproliferation of bone MKs may exist in most ITP patients. For obviating the nosogenetic factors, the normal MK releasing platelet could be easily found in the culture system. But the colony formation rate of MK decreased in a few patients with CITP. The abnormality of MK might be one of the reasons for thrombocytopenia in partial patients with ITP. Underproliferation of MKs may exist in AA, but no pathosishemogenesis was found. The dysfunction of early phase MK progenitor and stem cell might be the major reason for AA, but not the abnormality of hematopoietic microenvironment. There may be two kinds of megakaryocyte clones in bone marrow of children with MDS. One may be pathologic and potentially malignant micromegakaryocytes, the other may be the normal megakaryocytic precursors. The increase of pathologic MK resulted in abnormal development and maturation of MK in bone marrow. The change of megakaryopoiesis showed different in ITP, AA or MDS. Using bone marrow smear megakaryocyte counting, small micromegakaryocyte immunohistochemical detecting and the formation rate of bone marrow MK colony assay, the different thrombocytopenia can be diagnosed during the early stage of ITP, AA or MDS.

Adolescent ; Anemia, Aplastic ; blood ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Male ; Megakaryocytes ; pathology ; physiology ; Myelodysplastic Syndromes ; blood ; Purpura, Thrombocytopenic ; blood

OBJECTIVETo analyze the ultra microstructures and the expression of platelet peroxidase (PPO) of megakaryocytes from bone marrow, their clinical manifestations and laboratory characteristics in patients with acute megakaryoblastic leukemia (AMKL).

METHODSKaryocytes from bone marrow of 22 AMKL patients were divided into two parts by lymphocyte separation liquid, one part was used to prepare the ordinary transmission electron microscope specimens to observe the morphological structures of megakaryocytes, the other was used to prepare the histochemical specimens of platelet peroxidase to analyze the positive reaction of PPO in AMKL, which were coupled with the patients' data of with bone marrow morphology, cell chemistry, and chromosome karyotype examination.

RESULTSMegakaryocytes from 17 of 22 patients were in the first stage, less than 20 µm in diameter, the nucleis were round, the cytoplasm contained microtubules, membranous vesicles and minute dense granules, no demarcation membrane system and surface-connected canalicular system, less dense granules and α-granules; Megakaryocytes in 5 cases were mainly in the first stage, while containing second and third stage megakaryocytes; the positive rate of PPO in megakaryocytes of 22 patients was 0-80%. The primitive and naive megakaryocytes were found in bone marrow smears of 22 cases, CD41 staining of the megakaryocytes was detected in the primitive and naive megakaryocytes, and more complex chromosome karyotype anomalies were observed.

CONCLUSIONThe majority of megakaryocytes in AMKL patients were the first stage ones, the rest were second and third stage ones, and the positive PPO reaction was significantly different. CD41 staining of the megakaryocytes was specific with complex chromosome karyotypeswere.

Blood Platelets ; enzymology ; Bone Marrow ; pathology ; Cell Count ; Chromosome Aberrations ; Chromosome Disorders ; Humans ; Karyotyping ; Leukemia, Megakaryoblastic, Acute ; diagnosis ; pathology ; Megakaryocytes ; pathology ; Peroxidase ; metabolism ; Staining and Labeling

To observe the morphological characteristics and hematopoietic function of bone marrow megakaryocyte (MK) in children patients with idiopathic thrombocytopenic purpura (ITP), and to preliminary analyse the cause and mechanism of thrombocytopenia. CD41 McAb immunohistochemical technique was used to detect micromegakaryocyte in bone marrow smear. Plasma clot culture and CD41 McAb immunohistochemical technique were used for the MK-colony forming assay. The results showed that there was no statistical difference of the positive rate of micromegakaryocyte between groups of ITP and control, but type I lymphocyte-like micromegakaryocyte was infrequent. The number of micromegakaryocyte and the formation rates of CFU-MK and BFU-MK in ITP group were significantly higher than those in control group. The normal MK releasing platelet could be easily found in the culture system. The MK colony formation rate was decreased in a patient with chronic ITP. In conclusion, the increment of type II, III, IV micromegakaryocytes is one of pathologic phenomenon of ITP. These small megakaryocytes can develop and mature to normal megakaryocytes in the condition of ex vivo culture. The developmental abnormity of MK is a possible reason for thrombocytopenia among partial patients with ITP, especially the chronic cases.
Adolescent ; Bone Marrow Cells ; pathology ; physiology ; Child ; Child, Preschool ; Female ; Hematopoiesis ; Humans ; Immunohistochemistry ; Infant ; Male ; Megakaryocytes ; pathology ; physiology ; Platelet Membrane Glycoprotein IIb ; analysis ; Purpura, Thrombocytopenic, Idiopathic ; pathology ; physiopathology