Cytokine, chemokine and growth factor gene profiling of cultured human astrocytes after exposure to proinflammatory stimuli

Abstract

Astrocytes play key roles in CNS development, inflammation, and repair by producing a wide variety of cytokines, chemokines, and growth factors. Understanding the regulation of this network is important for a full understanding of astrocyte functioning. In this study, expression levels of 268 genes encoding cytokines, chemokines, growth factors, and their receptors were established in cultured human adult astrocytes using cDNA arrays. Also, changes in this gene profile were determined following stimulation with TNFalpha, IL-1beta, and IFNgamma. The data obtained reveal a highly reproducible pattern of gene expression not only between different astrocyte cultures from a single source, but also between astrocytes from different donors. They also identify several gene products not previously described for human astrocytes, including a.o. IL-17, CD70, CD147, and BIGH3. When stimulated with TNFalpha astrocytes respond with increased expression of several genes, notably including those encoding the chemokines CCL2 (MCP-1), CCL5 (RANTES), and CXCL8 (IL-8), growth factors including BMP-2A, BMP-3, neuromodulin (GAP43), BDNF, and G-CSF, and receptors such as the CRF receptor, the calcitonin receptor (CTR), and TKT. The response to IL-1beta involves largely the same range of genes, but responses were blunted in comparison to the TNFalpha response. Treatment with IFNgamma had no or only marginal effects on expression of any of the 268 genes analyzed. Astrocytes treated with a mixture of all three stimuli together displayed responses that are largely similar to those found in response to TNFalpha or IL-1beta alone, with only few additional synergistic effects.

Interleukin-17 Production in Central Nervous System-Infiltrating T Cells and Glial Cells Is Associated with Active Disease in Multiple Sclerosis

“…22 Indeed, not only was IL-17 mRNA detected in an earlier study in astrocytes cultured from adult donors in a gene array analysis, 37,42 but it was also up-regulated after treatment with tumor necrosis factor-␣ or IL-1␤, but not, interestingly, with interferon-␥. 43 Again, this agrees with the known polarization of T H 17 cells by such proinflammatory cytokines as IL-6, tumor necrosis factor-␣, and IL-1␤.…”

Synergistic increases in intracellular Ca2+, and the release of MCP‐1, RANTES, and IL‐6 by astrocytes treated with opiates and HIV‐1 Tat

“…The CC chemokines MCP-1 and RANTES, which are major attractants for monocyte/macrophage entry into the CNS and key initiators of proinflammatory cascades (Luo et al, 2002a), have been found in the brain tissue and cerebrospinal fluid of patients with HIV-1 encephalitis and AIDS dementia complex (Kelder et al, 1998;McManus et al, 2000). Although the cytokine array is sensitive and can reportedly detect protein levels as low as 4 pg/ml (compared to 40 pg/ml with ELISA), we did not see increases in TNF-α release at 4 or 12 h. Increases in TNF-α were anticipated because Tat has been previously reported to increase TNF-α expression in astrocytes (Chen et al, 1997) and TNF-α can induce the expression of IL-6 (Norris et al, 1994), MCP-1 (Oh et al, 1999;Luo et al, 2003), and RANTES (Oh et al, 1999;Meeuwsen et al, 2003) in human and/or mouse astrocytes. Importantly, we found large relative increases in TNF-α mRNA levels at 30 min and declining levels thereafter in response to Tat 1-72 exposure.…”

Neuroprotective Effect of Recombinant Human Granulocyte Colony-Stimulating Factor in Transient Focal Ischemia of Mice

“…Nevertheless, G-CSF treatment significantly increased the number of intrinsic Iba-1-positive microglia. While several studies examined the relationship between astrocytes and G-CSF (Meeuwsen et al, 2003), to our knowledge, our study is the first that reports G-CSF-induced microglial activation. Microglia/macrophages are considered the major source of inflammatory cytokines in the ischemic brain (Gregersen et al, 2000;Lambertsen et al, 2002).…”