We examined the effect of mechanical fluid flow and surfactant oil macropha
ge aggregation a, the indication of macrophage activation. Mechanical fluid
flow enhanced aggregation in phorbol myristate, acetate (PMA)-treated huma
n myeloid leukemic cell lines (HL-60 cells), but had no effect on different
iation of PMA-treated HL-60 cells. Surfactant-TA (an artificial surfactant)
inhibited fluid flow-induced aggregation, but had no effect on differentia
tion of PMA-treated HL-60 cells. Human alveolar macrophage, spontaneously f
ormed small aggregates without stimulation. This aggregation was enhanced b
y fluid flow and inhibited by surfactant-TA. Taken together, these data sug
gest that macrophage activation is affected by fluid flow and surfactants.