Proliferation kinetics and PCNA expression of HL-60 cells following ionizing irradiation and granulocytic differentiation.
The human promyelocytic leukaemia cell line, HL-60, was investigated with regard to proliferation and terminal differentiation following irradiation. The cells were X-irradiated and induced with 1.25% dimethyl sulfoxide (DMSO) towards the granulocytic lineage. Proliferation was measured via cell growth, clonogenicity and the bromodeoxyuridine/DNA incorporation assay. Immunohistochemical detection of proliferating cell nuclear antigen (PCNA) expression was used to discriminate cycling from non-cycling cells. The differentiation obtained was proved by testing for the immune function of the respiratory burst (NBT reduction test). The HL-60 cells studied revealed a high radiosensitivity (D0 = 0.63 Gy). After induction with DMSO, declines in cell growth, clonogenicity and PCNA positivity of the cells indicated a decrease in proliferation and an increase in differentiation. Starting on day 2 in culture, irradiation after seeding with 1 Gy accelerated the loss of the PCNA expression in induced cells (46% v. 3% PCNA-negative control cells on day 3). Induced cells gained the capability of exerting the respiratory burst, which was found to be dose-dependent radiosensitive (42%, and 12% NBT-positive cells after 1 and 2 Gy, respectively, v. 53% NBT-positive control cells on day 8). Subpopulations in the cell line were evident in all parameters investigated. We discuss the HL-60 cell, not only as a model comparable to human progenitor cells, but also as a suitable tool in radiobiological research with regard to proliferation and differentiation following ionizing irradiation.
Sendler
A
A
Institute of Radiobiology, Federal Armed Forces Medical Academy, Munich, Germany.
Kaffenberger
W
W
Nuyken
I
I
van Beuningen
D
D
D002453:Cell Cycle; D002454:Cell Differentiation; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004307:Dose-Response Relationship, Radiation; D006098:Granulocytes / Q000378:metabolism*; D006801:Humans; D007942:Leukemia, Experimental; D015473:Leukemia, Promyelocytic, Acute / Q000378:metabolism*; D018809:Proliferating Cell Nuclear Antigen / Q000096:biosynthesis*; D011830:Radiation Effects; D016897:Respiratory Burst; D014965:X-Rays
D018809:Proliferating Cell Nuclear Antigen; D004121:Dimethyl Sulfoxide