megakaryocyte


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megakaryocyte

 [meg″ah-kar´e-o-sīt″]
the giant cell of bone marrow; it is a large cell with a greatly lobulated nucleus, and is generally supposed to give rise to blood platelets.

meg·a·kar·y·o·cyte

(meg'ă-kar'ē-ō-sīt),
A large cell (as much as 100 mcm in diameter) with a polyploid nucleus that is usually multilobed; megakaryocytes are normally present in bone marrow, not in the circulating blood, and give rise to blood platelets.
[mega- + G. karyon, nut (nucleus), + kytos, hollow vessel (cell)]

megakaryocyte

/mega·karyo·cyte/ (-sīt″) the giant cell of bone marrow containing a greatly lobulated nucleus, from which mature blood platelets originate.megakaryocyt´ic

megakaryocyte

(mĕg′ə-kăr′ē-ō-sīt′, -ə-sīt′)
n.
A large bone marrow cell with a lobulate nucleus that gives rise to blood platelets.

megakaryocyte

[meg′əker′ē·əsīt′]
Etymology: Gk, megas, large, karyon, nut, kytos, cell
bone marrow cell measuring 35 to 160 μm in diameter and having a multilobed nucleus. Megakaryocytes are platelet precursors. Also spelled megacaryocyte. See also platelet. megakaryocytic, adj.

megakaryocyte

A very large cell native to the bone marrow which is the precursor of platelets and the largest (40–100 µm in diameter) normal nucleated haematopoietic cell in the marrow. Megakaryocytes may be relatively small (micromegakaryocytes) and measure 15–30 µm in diameter. The nucleus usually has multiple (8, 16 or 32) overlapping lobes; megakaryocytes with few (2 or 4) lobes may occur in myelodysplasia. Nucleoli are absent, chromatin is coarse, cytoplasm is abundant, stains light blue or pink, and contains numerous purplish-red or pink granules. The N:C ratio is 1:1 to 1:2. Megakaryocytes producing platelets may reveal demarcated granular clumps of platelets extruding/streaming from the margins (platelet budding).

meg·a·kar·y·o·cyte

(meg'ă-kar'ē-ō-sīt)
A large cell with a multilobed nucleus; normally present in bone marrow, not in the circulating blood; gives rise to blood platelets (thrombocytes).
Synonym(s): megalokaryocyte.
[mega- + G. karyon, nut (nucleus), + kytos, hollow vessel (cell)]
Enlarge picture
MEGAKARYOCYTE: (Orig. mag. ×640)
Enlarge picture
MEGAKARYOCYTE

megakaryocyte

(meg?a-kar'e-o-sit?) [? + karyon, nucleus, + kytos, cell]
Large bone marrow cell with large or multiple nuclei from which platelets are derived.
See: platelet; illustrationillustration

megakaryocyte

An unusually large bone marrow cell that releases many small fragments of its CYTOPLASM as the blood PLATELETS essential for clotting (blood coagulation).

Megakaryocyte

A large bone marrow cell with a lobed nucleus that is the precursor cell of blood platelets.

megakaryocyte

large nucleated cell within bone marrow (but not circulating blood), fragments of which form platelets

megakaryocyte

the giant cell of bone marrow; it is a large cell with a greatly lobulated nucleus and gives rise to blood platelets.
References in periodicals archive ?
CLT-009, a human Megakaryocyte Progenitor Cell product, would be an alternative treatment option, providing the critical megakayocyte progenitor cellular support to rapidly produce platelets in vivo and shorten the duration of severe thrombocytopenia following chemotherapy treatment.
Megakaryocytes bind the protein to produce thrombocytes in the bone marrow, and circulating platelets bind and remove thrombopoietin from the circulation, resulting in a feedback mechanism (Nathan and Orkin 1998).
Myeloid recovery was defined as an absolute neutrophil count of more than 500/[micro]L, and erythroid and megakaryocyte lineage reconstitution were defined as reticulocyte counts of more than 3 x [10.
Reticulated platelets (retPLTs) are platelets that are newly released from bone marrow megakaryocytes and still contain RNA.
Megakaryocytes are also formed during myelopoiesis and these ultimately liberate cytoplasmic contents into the circulation as platelets.
Blood First Edition Paper, prepublished online, 13 November 2007, PACAP and its receptor VPAC1 regulate megakaryocyte maturation: therapeutic implications.
T suppressor activated lymphocytes (CD8+/DR+) inhibit megakaryocyte progenitor cell differentiation in a case of acquired amegakaryocytic thrombocytopenic purpura.
Platelet production is dependent on adequate marrow function and a quantitatively and qualitatively sufficient megakaryocyte population.
Interleukin-1 is a potent inducer of IL-6, and the combination of IL-1 and IL-6 can act as a megakaryocyte potentiator as well.
Nplate binds to the TPO receptor, which activates the pathway necessary for growth and maturation of bone marrow megakaryocyte cells, resulting in increased platelet production.
Acute myeloid leukaemia of mixed megakaryocyte and erythroid origin: a case report and review of the literature.
In cases of autonomous platelet hyperproduction, one could expect a diminished control by the megakaryocyte of the platelet size, reflected by a widened dispersion.