Heterogeneity of cellular expression of arachidonate 15-lipoxygenase: implications for biological activity.

Comparison of relative arachidonate 15-lipoxygenase activities in different types of human cell reveals striking differences in levels of product generation. Among available human cell types, the tracheal epithelial cell and the eosinophil have markedly higher levels of activity than other cell types with reported activity. Theories of functional significance for this enzymatic pathway will need to account for the selective expression of high levels of activity in a highly limited number of cell types.