International Journal of Cell Cloning, Vol 7, 292-302, Copyright © 1989 by AlphaMed Press
A subline of the Brown Norway myeloid leukemia in the Lewis x Brown Norway rat: in vivo growth characteristics and development of an in vitro clonogenic assay
JM Wiley, AM Yeager, RJ Johnson and M Lanotte
Oncology Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
A subline of Brown Norway (BN) acute myelocytic leukemia (AML) which can be
propagated in suspension culture (designated IPC-81) is described.
Injection into Lewis x BN F1 hybrid (LBN) rats resulted in a log-linear
correlation between tumor cell dose and time till death from the onset of
leukemia even after multiple (greater than 16) passages in vitro. An in
vitro clonogenic assay for IPC-81 colony formation (CFU- leuk) was
developed with excellent cloning efficiency (55-82%). Colonies grew without
the addition of specific growth factors; syngeneic spleen-conditioned
medium inhibited CFU-leuk by 40%, but co- culture with untreated normal LBN
rat bone marrow cells had no effect on CFU-leuk. CFU-leuk could be detected
in the bone marrow 7 to 10 days before morphologic detection of leukemia in
injected animals. This cell line should prove useful in the preclinical
evaluation of new strategies for treating AML and evaluating new bone
marrow purging methods.
