These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Lipopolysaccharide-induced IL-12 expression in the central nervous system and cultured astrocytes and microglia.
    Author: Stalder AK, Pagenstecher A, Yu NC, Kincaid C, Chiang CS, Hobbs MV, Bloom FE, Campbell IL.
    Journal: J Immunol; 1997 Aug 01; 159(3):1344-51. PubMed ID: 9233631.
    Abstract:
    We examined whether the cytokine IL-12 could be induced locally in the brain or in glial cell cultures following LPS treatment. In the brain, expression of IL-12 p35 mRNA was constitutive and did not alter following i.p. injection of LPS. In contrast, IL-12 p40 mRNA was only detectable in the brain of mice given two staggered injections of LPS. Dual labeling in situ analysis revealed IL-12 p40 RNA-positive cells scattered throughout the brain parenchyma, with a small number of these cells being identified as astrocytes, while the majority of IL-12 p40 RNA-expressing cells appeared to be microglia. In cultured microglia or astrocytes, LPS and to a much lesser degree IL-1beta, but not IFN-gamma or TNF-alpha, induced the expression of IL-12 p40 mRNA. Numerous glial fibrillary acidic protein-immunopositive cells colabeled for IL-12 p40 RNA; indicating that LPS-stimulated astrocytes expressed IL-12 in vitro. Immunoblot analysis of lysates from LPS-treated astrocytes revealed the presence of multiple species of 40, 43, 75, and 120 kDa containing the IL-12 p40 protein. Finally, secretion of the IL-12 p75 heterodimer was detectable by ELISA from astrocytes treated with LPS plus IFN-gamma, but not with LPS alone. The findings indicate that IL-12 gene expression can be activated in the brain, with the resident glial cells being a prodigious source of this cytokine. The localized production of IL-12 may have a significant impact on the development of cell-mediated immune responses within the central nervous system.
    [Abstract] [Full Text] [Related] [New Search]