Iron metabolism in reticuloendothelial cells.

Metabolism of iron within cells of the RE system is less well understood than any other aspect of iron metabolism. Only with respect to the activity of microsomal heme oxygenase does any precise knowledge exist. Sequestration, phagocytosis, control of iron movement into and out of storage pools and between storage substances, regulation of release, and disturbances in disease states can only be discussed in broad outline. The absence of precise information is reflective of the difficulties inherent in studying the system. Interpreting data obtained from various animal models has been difficult, in part perhaps because subtle differences in the behavior of RE cells in different organs tend to blur outcomes which might be clearcut if uniform populations could be studied. Efforts to control these variables by employing cell cultures of various origins have been reported, 19,22,39,60,65,66,93 but there has been no systematic use of such in vitro models. Regardless of how the RE system is studied, however, it seems likely that until the assumptions upon which a model is based are thoroughly understood, little useful information can be expected.