Differential biologic effects resulting from bimodal binding of recombinant
human tumor necrosis factor to myeloid leukemia cells
H Ishikura, K Hori and A Bloch
Department of Experimental Therapeutics, Roswell Park Memorial Institute,
Buffalo.
Human recombinant tumor necrosis factor (rTNF) bound to ML-1 and HL-60
human myeloid leukemia cells in a bimodal manner. Saturable high- affinity
binding was maximal at approximately 3 nmol/L rTNF, whereas saturable
low-affinity binding reached its maximum at approximately 30 nmol/L. As
analyzed by computer program, the observed data fit a two- receptor site
model, with p less than .05. High-affinity binding concentrations of rTNF
caused the differentiation of both cell lines, whereas low-affinity binding
concentrations abolished this effect in a concentration-dependent manner.
Thus, the type of biologic response elicited with rTNF in these cells is a
function of the concentration at which the factor is applied. If generally
applicable, this bimodal effect may require consideration when rTNF is to
be used therapeutically.
Volume 73,
Issue 2,
pp. 419-424,
02/01/1989
Copyright © 1989 by The American Society of Hematology
