International Journal of Cell Cloning, Vol 5, 220-230, Copyright © 1987 by AlphaMed Press
Protoplast-mediated gene transfer into human leukemia (K562) cells
CJ Tsao, T Hosoi, H Hirai, T Saito, T Okabe, A Urabe and F Takaku
We have examined the usefulness of a protoplast fusion technique as a tool
to transfer cloned genes into hematopoietic cells. Protoplasts carrying
cloned plasmids, which would express specific markers when successfully
transfected into human cells, were prepared and fused with human leukemic
cell line K562 cells using polyethylene glycol as a fusogenic factor. As a
result, K562 cells fused with protoplasts containing a plasmid pSV2-cat
constructed to code for chloramphenicol acetyltransferase (CAT) expressed
CAT activity efficiently. K562 cells were also readily transformed to
geneticin-(G418) resistant cells following fusion with protoplasts carrying
a plasmid pSV2-neo-SV-gpt, which confers the resistance of mammalian cells
to G418 and mycophenolic acid. It was also demonstrated that the plasmid
genome was stably integrated into the chromosomal DNA of G418-resistant
K562 cells. Our results proved that protoplast fusion could be used to
study the specific expression and the biologic activities of cloned genes
in human hematopoietic cells.
