Establishment of a Novel Human Macrophage-Like Cell Line, MABS-1, Derived from a Human Monocytic Leukemia Cell Line, MOBS-1

A human macrophage-like cell line, MABS-1, was established from adherent colonial cells that appeared in a culture of a monocytic leukemia cell line, MOBS-1, established from peripheral blood mononuclear leukocytes of a patient with monocytic leukemia (M5b) . These cell lines were of monocyte/ macrophage lineage, because both MOBS-1 and MABS-1 cells have activities of phagocytosis, α-naphthyl butyrate esterase, and express HLA-DR. MABS-1 cells werr larger and had wider cytoplasm that did MOBS-1 cells and tightly adhered to plastic and glass with pseudopodia and microvilli. Furthermore, MABS-1 cells, but not MOBS-1 cells, had the following characteristics of macrophages. They expressed CD68 (KP-1 antigen) in cytoplasm and CD14 on the cell surface. Generation of superoxide anion, a sign of activated phagocytes, was detected in MABS-1 cells by nitroblue tetrazolium reduction without phorbol ester stimulation. Modes of chromosome numbers of MABS-1 and MOBS-1 clels were 75 and 53, respectively, and karyotypic abnormalities detected in these cell lines with trypsin-Giemsa G-banding methods agreed at 3 points and disagreed at 25 points. However, DNA fingerprint analysis of mitochondrial DNA D-loop regions revealed that the hereditary relationship between these cell lines was close. These data suggest that MABS-1 cells originate from MOBS-1 cells but are more differentiated toward the macrophage direction than are the parent MOBS-1 cells.