Abstract
Modulation of IFN-γ production from T cells by smokeless tobacco extract (STE) could be a factor in periodontal disease. The major inducer of IFN-γ from T cells is bioactive IL-12 (p70), a heterodimeric protein composed of p35 and p40 subunits, while homodimeric IL-12 p40 antagonizes bioactive IL-12. Both p70 and p40 are produced by macrophages in response to lipopolysaccharide (LPS), IFN-γ and/or CD40 ligation. To determine the impact of STE on IL-12 p40, p70 and IFN-γ, splenic T cells were stimulated with anti-CD3 while splenic macrophages were stimulated with LPS in the presence or absence of STE. Production of IL-12 p40 and p70 from LPS-stimulated splenic macrophages and IL-12 p40, p70 and IFN-γ from LPS/anti-CD3-stimulated T cells and macrophages was decreased by STE. To determine the impact of STE on macrophage IL-12 production alone, splenic or peritoneal macrophages were enriched and then stimulated. STE significantly diminished production of IL-12 p40 and p70 from LPS-stimulated peritoneal macrophages, LPS/IFN-γ-stimulated peritoneal and splenic macrophages, but increased production of IL-12 p40 and p70 from IFN-γ/CD40-stimulated splenic macrophages or IFN-γ-stimulated peritoneal macrophages. None of the effects of STE on IL-12 was due to nicotine, rutin or chlorogenic acid. In contrast to STE, nicotine at 100 μg/ml significantly elevated production of IL-12 p40 and p70 from splenic macrophages stimulate by IFN-γ/LPS. The results indicate that STE has a significant overall effect upon IL-12 production. It suppresses p40 and p70 production during responses to LPS or LPS/IFN-γ but augments p40 and p70 production during responses to IFN-γ without LPS. This affect could have a major impact on diseases associated with excessive production of IL-12.
Original language | English (US) |
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Pages (from-to) | 345-355 |
Number of pages | 11 |
Journal | International Immunopharmacology |
Volume | 2 |
Issue number | 2-3 |
DOIs | |
State | Published - 2002 |
Keywords
- IL-12
- Macrophages
- Mice
- T cells
- Tobacco
ASJC Scopus subject areas
- Immunology and Allergy
- Immunology
- Pharmacology