COMPARATIVE-STUDIES ON FUNCTIONAL AND SECRETORY PROPERTIES OF MACROPHAGE CELL-LINES DERIVED FROM DIFFERENT ANATOMICAL SITES

In the present study, we compared four macrophage (M phi) cell lines f rom different anatomical origins for functional and secretory activiti es against the two morphogenetic forms of the fungus Candida albicans. We show that all the cell lines actively phagocytize the yeast and ex ert antimicrobial activity against both forms of Candida, although M p hi of microglial origin are the most effective. When assessed for secr etory properties, microglial M phi exhibit a peculiar pattern with res pect to other M phi populations under either basal or stimulated condi tions. In particular, only microglial M phi fail to respond to the hyp hal form of the fungus (H-Candida), which instead acts as a potent tum or necrosis factor inducer in the other M phi cell lines. When exposed to H-Candida, microglial M phi are indistinguishable from other M phi in their ability to modulate specific surface adhesion molecules. In addition to strengthening the knowledge on functional heterogeneity am ong M phi, our data provide evidence on the peculiar behavior of micro glial M phi. To what extent M phi heterogeneity may be related to tiss ue homeostasis is discussed.