myeloblast


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Related to myeloblast: myeloblastic leukemia

myeloblast

 [mi´ĕ-lo-blast″]
an immature cell of bone marrow, not normally found in peripheral blood; it is the most primitive precursor in the granulocytic series, which develops into the promyelocyte and eventually into a granulocyte.

my·e·lo·blast

(mī'ĕ-lō-blast),
An immature cell (10-18 mcm in diameter) in the granulocytic series, occurring normally in bone marrow, but not in the circulating blood (except in certain diseases). When stained with the usual dyes, the cytoplasm is light blue, nongranular, and variable in amount, sometimes being only a thin rim around the nucleus; the latter is deep purple-blue with finely divided, punctate, threadlike chromatin that is somewhat condensed at the periphery. A few light blue nucleoli are usually present in the nucleus, and these generally disappear as the myeloblast matures into a promyelocyte and then a myelocyte. Myeloblasts ordinarily yield a negative reaction with peroxidase.
[myelo- + G. blastos, germ]

myeloblast

(mī′ə-lə-blăst′)
n.
An immature cell of the bone marrow that is the precursor of a myelocyte.

my′e·lo·blas′tic adj.

my·e·lo·blast

(mī'ĕ-lō-blast)
An immature cell in the granulocytic series, occurring normally in bone marrow but not in the blood. When stained, the cytoplasm is light blue and variable in amount; the nucleus deep purple-blue with finely divided, punctate, threadlike chromatin. A few light blue nucleoli in the nucleus generally disappear as the myeloblast matures into a promyelocyte and then a myelocyte.
[myelo- + G. blastos, germ]

myeloblast

The bone marrow cell from which the whole series of granular white blood cells (GRANULOCYTES) derives. Up to 3% of bone marrow cells are myeloblasts.
References in periodicals archive ?
Marrow biopsy revealed 84% myeloblasts with del (15q) in all 20 analyzed cells and new del (16q) in 1 of 20 cells.
Myeloblasts are less than 5% of all cells, and maturing granulocytes are readily identified.
A 71-year-old female with a history significant for hypertension, hepatitis B, and hypothyroidism, underwent bone marrow biopsy which showed a hypercellular bone marrow with >90% cellularity and 81% myeloblasts expressing CD 34 and CD 117 markers, confirming a diagnosis of acute myeloid leukemia (AML).
Tailler et al., "A novel effect of DNA methyltransferase and histone deacetylase inhibitors : NF[kappa]B inhibition in malignant myeloblasts," Cell Cycle, vol.
The bone marrow examination then showed 90% myeloblasts, with immunophenotype CD45dim/117+/13dim/33+/56-/2-/15-/ 14-/11b-/99+/HLA-DR-; CD34 positivity was detected for a subpopulation of 8% of blasts.
Immature myeloid cells or extramedullary proliferation of myeloblasts are present in MS [2].
Undoubtedly, blast crisis, defined as >30% myeloblasts in the circulation [10-12], represents a critical turning point in the CML course triggering a rapid clinicobiological worsening with poor outcomes [10].
The myeloblasts and megakaryocytes were normal in number and morphology; M : E ratio was 6: 1.
It is not unusual to identify two distinct blast populations in the same patient, one of small size with a high nucleus/cytoplasm ratio resembling lymphoblasts and the other larger with more abundant cytoplasm with or without granulation resembling myeloblasts.
Gate D (pink) is shown here in the area typically occupied by myeloblasts, but may be used to highlight other populations.
In more than 90% of patients suffering from acute myeloid leukaemia, CD33 has been recognised to be the antigen expressed on the surface of myeloblasts. By binding to the CD33 antigen on the cell surface, Mylotarg is absorbed into the cell and calicheamicin is released, causing death to the cancer cell.
MYLOTARG is an antibody-drug conjugate (ADC) composed of the cytotoxic agent calicheamicin, attached to a monoclonal antibody (mAB) targeting CD33, an antigen expressed on the surface of myeloblasts in up to 90 percent of AML patients.