CONICET | Buscador de Institutos y Recursos Humanos

Microglial are cells of myeloid origin that populate the central nervous system (CNS) during early development and form the brain´s innate immune cell type. In particular, after injuries involving tissue loss, microglial recruitment and activation processes seem crucial to obtain a restorative environment. The microglia phagocytic activity clears cell debris and renders a permissive environment for tissue repair initiation and neuronal circuit rewiring. In fact, inadequate debris clearance is associated with a deficient regenerative response (Neumann et al., 2008). Transferrin (Tf) is a glycoprotein best known for its role in iron delivery. However, multiple functions have been attributed to Tf. In some tissues, it has been reported to favour proliferation and differentiation of certain cell types. As a matter of fact, previous studies done in our laboratory have shown that apoTf accelerates the differentiation of oligodendrocytes in vitro and in vivo (Escobar Cabrera et al., 1997; Paez et al., 2005). Here, we described the expression of transferrin receptor and Tf incorporation by microglial cells. We determined the effects that Tf addition to the culture medium has on microglia viability, proliferation, cellular death, phenotype and phagocytic capacity. Our results indicate that Tf would be modulating the proliferation of microglial cells induced by LPS. aTf addition produces a significant increase of basal microglia metabolicactivity, which is consistent with its increased proliferative rate, while its death rate remains unchanged. This enhanced metabolic rate does not owe to microglial activation, since expression levles of CD11b do not change significantly.Moreover, microglial treatment effects on astrocytes and oligodendrocytes. When microglia is activated with LPS, there is a significant decrease of both GFAP+ and MBP+ cells relative to the control condition.