Monokine production by microglial cell clones

Cytokines have been suggested to act as intermediates between the immune and the central nervous system, but little is known about the type of cells synthesizing them in the brain. We have immortalized with oncogenic retroviruses primary brain cell cultures from mouse embryos and have generated clones of microglial cells that have been characterized. Three of the clones studied produce interleukin 1 (IL 1), IL 6 and tumor necrosis factor-? as assessed by biological assays and by Northern blot analysis. Our data raise the question on the role of these cytokines in the brain and suggest that early resident microglial cells might play an important role in developmental processes and in the adult brain.