Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Multiple monoclonal antibodies and enzyme assays were used to study maturity markers (myelo-peroxidase) and immaturity markers (terminal transferase, HLA-2) in acute myeloid leukemia cells from 35 patients. In 8 of the patients, indications were found of an expression of maturity and immaturity markers on the same cells, here in called maturation asynchrony. It is suggested that the orderly appearance and disappearance of markers during the maturation of normal cells is disordered in malignant cells, and that single markers should be used with caution for the maturation classification of tumors. The simultaneous expression of maturity and immaturity marker by tumor cells could explain also why such cells can be recognized as abnormal even in the absence of tumor specific antigens.
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PMID:Maturation asynchrony in leukemic cells. An abnormal combination of normal cell markers. 299 49

Hematopoietic progenitor cells from different sources have been widely characterized, but their ultrastructural morphology has never been described in detail. In this study, imunomagnetically separated CD34+ cells from normal bone marrow (BM), mobilized peripheral blood (PBSC) and human umbilical cord blood (CB) were studied by transmission electron microscopy (TEM) using a cytochemical method which reveals endogenous myelo-peroxidase (MPO) activity. This technique is particularly suited for detecting early signs of the myeloid commitment. The CD34+ cells from PBSC were morphologically very homogeneous and 94.7+/-4.5% of these cells were MPO-: these ultrastructural features are generally considered typical of immature cells. The CD34+ BM cells were instead more heterogeneous, with 24.6+/-7.4% showing intense MPO activity. The ultrastructural characteristics of CB cells fell between those observed in PBSC and BM, but there was a high percentage of morphologically immature cells with no evidence of MPO activity (about 83%). The number of apoptotic cells within samples from different sources was also examined both by TEM and flow cytometry. The percentage of apoptotic cells was 0.7% in PBSC, 2.3% in BM, 2.9% in CB from vaginal delivery and 11.6% in CB from cesarean section. These observations confirm the relative phenotypic immaturity of CB in comparison with BM cells; they also suggest that CB collected after cesarean section may be associated with reduced stem cells viability.
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PMID:Ultrastructural features of CD34+ hematopoietic progenitor cells from bone marrow, peripheral blood and umbilical cord blood. 1169