Human chronic myelogenous leukemia cell-line with positive Philadelphia chromosome

Abstract

A cell-line derived from a patient with chronic myelogenous leukemia (CML) is described. The new cell-line, which has over 175 serial passanges in a 3 1/2-yr period, has the following characteristics: (1) CML cells started to proliferate actively since they were first incubated in culture media. A threefold increase in the total number of cells was observed during the first seven passages; the cell population increased by a factor of 10 to 20 every 7 days from passage 8 through 85; from 20 to 40 times from passage 86 through 150, and more than 40 times after 150 passages. (2) The majority of the nononucleated cells are undifferentiated blasts. (3) The karyotype of all the cells examined show the Philadelphia (Ph1) chromosome and a long acrocentric marker plus aneuploidy. The Giemsa-banding studies identified the Ph1 chromosome as a terminal deletion of the long arm of chromosome 22:del(22)(q12) and the long acrocentric marker as an unbalanced reciprocal translocation of one chromosome 17 and the long arm of one chromosome 15. (4) The CML cells do not produce immunoglobulins, are free of mycoplasma, Epstein-Barr virus, and herpes-like virus particles. (5) CML cells have no alkaline phosphatase and myeloperoxidase activities and did not engulf inert particles. (6) Cultured CML cells provide a constant source of a specific antigen. This CML cell-line represents a unique source of CML cells with meaningful indicators of malignancy for clinical and experimental studies.

NF-E2 Disrupts Chromatin Structure at Human β-Globin Locus Control Region Hypersensitive Site 2 In Vitro

“…MEL extract preparation. MEL cells (30) were grown in ␣ minimal essential medium with 10% calf serum and 1ϫ penicillin-streptomycin-L-glutamine and induced with N,NЈ-hexamethylene bisacetamide (HMBA) at 5 mM 36 to 48 h prior to extract preparation. All centrifugation steps were carried out at 4ЊC.…”

Trafficking defects of the Southeast Asian ovalocytosis deletion mutant of anion exchanger 1 membrane proteins

“…Co-expressing AE1 and AE1 SAO in oocytes did not interfere with the trafficking of AE1 to the surface [22], although hetero-oligomerization was not shown in this study. AE1 SAO has also been stably expressed in K562 cells [24], a human erythroleukaemia cell line that expresses GPA [25]. The presence of Wr b epitopes on K562 cells transfected with AE1 SAO demonstrates that AE1 SAO is able to interact with GPA.…”

The β-globin dominant control region activates homologous and heterologous promoters in a tissue-specific manner

“…We then asked the question whether the minilocus construct would be active in erythroid cells representing a different stage of development or in a non-erythroid cell line. The human cell line K562 (Lozzio and Lozzio, 1975), which expresses the human y-, but not the 8-globin gene, was chosen for the first purpose, since it had been shown previously that transfected y-, but not @globin genes (without flanking regions) can be expressed in these cells (Kioussis et al, 1985;Antoniou et al, 1987;Rutherford and Nienhuis, 1987). Mouse L cells were chosen as a nonerythroid cell, since it has been shown that this cell is capable of expressing transfected 6-globin genes (Dierks et al, 1981;Busslinger et al, 1983;Murray and Grosveld, 1987).…”