DIFFERENTIAL EXPRESSION OF FIBROBLAST GROWTH-FACTOR RECEPTORS BY HUMAN NEURONS, ASTROCYTES AND MICROGLIA

EXPRESSION Of fibroblast-growth factor receptors (FGFRs) was studied i n human fetal neurones, astrocytes and microglia in culture. Northern blot analysis showed that neurones and microglia expressed the mRNAs f or FGFR-1, FGFR-2, FGFR-3, FGFR-4 at different levels, whereas astrocy tes expressed only FGFR-1 and FGFR-4 mRNAs. Immunocytochemical localiz ation of FGFR-1 revealed that this receptor was predominantly localize d on the axon hillock membrane in neurones, and was associated with th e plasma membrane of ameboid, activated microglia and of glial-fibrill ar acidic protein positive astrocytes. The expression of various membe rs of the FGFR family in all the cell types investigated implicates FG Fs in human brain development and functions.