Macrophage colony-stimulating factor is produced by human T lymphoblastoid cell line, CEM-ON: identification by amino-terminal amino acid sequence analysis.
A subclone, designated CEM-ON, derived from an azaguanine-resistant human leukemic T cell line, CEM-AG(R), constitutively secretes a colony-stimulating factor (CSF) which stimulates the production of macrophages from murine bone marrow progenitor cells. This CSF has been purified from serum-free conditioned medium. Highly purified CEM-ON CSF with a specific activity of 4.7 X 10(7) units/mg protein was obtained. Amino-terminal sequence analysis showed that the first 27 amino acids were identical to the amino-terminal sequence of the M-CSF (CSF-1) based on the cDNAs for human M-CSF. On SDS-PAGE analysis, CEM-ON CSF had an apparent molecular weight of 33,000-43,000; following reduction with 2-mercaptoethanol, this migrated as a 20,000-24,000 subunit, suggesting a homodimer structure. These results show that a human T cell line, CEM-ON, secretes M-CSF into its medium.
Takahashi
M
M
Laboratories of Cellular Technology, Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan.
Hong
Y M
YM
Yasuda
S
S
Takano
M
M
Kawai
K
K
Nakai
S
S
Hirai
Y
Y
D000595:Amino Acid Sequence; D002460:Cell Line; D003115:Colony-Stimulating Factors / Q000096:biosynthesis*; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007938:Leukemia / Q000097:blood*; D008264:Macrophages / Q000378:metabolism*; D008970:Molecular Weight; D013601:T-Lymphocytes / Q000378:metabolism*
D003115:Colony-Stimulating Factors