Cytokine regulation of CC and CXC chemokine expression by XXXX astrocytes.

@entity1 @entity650 @entity5737 @entity1356 @entity310 @entity687 @entity2842 @entity2533 @entity379 @entity816 @entity371
Chemokines constitute a large family of secreted proteins that function as chemoattractants and activators of leukocytes. Astrocytes, the major glial cell type in the central nervous system (CNS), are a source of chemokine production within diseased brain. As such, we have examined the production of chemokines by @entity1 @entity816 cell lines and primary @entity1 astrocytes treated with a variety of stimuli, including LPS, @entity310 , @entity379 and @entity1356 . In addition, @entity650 in conjunction with the soluble @entity650 receptor (sIL-6R), and hybrid @entity650 (H- @entity650 ), a highly active fusion protein of sIL-6R and @entity650 , were tested for their ability to induce chemokine expression. The findings presented herein demonstrate that both @entity1 @entity816 cell lines and primary @entity1 astrocytes express the CXC chemokines @entity371 and @entity687 and the CC chemokines @entity2842 and @entity5737 in response to @entity310 and @entity1356 . @entity379 induced the expression of @entity371 , but not of @entity687 , @entity2842 or @entity5737 . Surprisingly, @entity650 /sIL-6R and H- @entity650 had little or no effect on chemokine expression in these cells. The effect of @entity2533 on chemokine expression in @entity1 @entity816 cell lines and astrocytes was also examined. @entity2533 alone had little or no effect on @entity5737 , @entity2842 and @entity687 expression; however, @entity2533 synergized with @entity310 to enhance @entity2842 expression in both @entity816 cells and primary astrocytes. An inhibitory effect of @entity2533 on @entity310 and @entity1356 induced @entity5737 and @entity687 expression was observed in @entity1 @entity816 cells. In contrast, @entity2533 enhanced @entity310 and @entity1356 induction ofIL-8 production by @entity1 astrocytes. These findings document a complex pattern of chemokine regulation by the pleiotropic cytokine @entity2533 with both enhancing and inhibitory effects.
