| Abstract | The expression of various cell surface molecules and the production of certain cytokines are important mechanisms by which dendritic cells (DC) are able to bias immune responses. This paper describes the effects of the inflammatory cytokine tumor necrosis factor (TNF)-alpha on DC phenotype and function. TNF-alpha treatment resulted in upregulation of MHC class II and CD86 in the absence of increased cell surface CD40 and CD80 or the production of IL-12. Additionally TNF-alpha treated cells were able to bias T cell responses towards an anti-inflammatory profile. On a note of caution this tolerogenic phenotype of the DC was not stable upon subsequent TLR-4 ligation as a 4 hour pulse of the TNF-alpha treated DC with lipopolysaccharide (LPS) resulted in the restoration of IL-12 production and an enhancement of their T cell stimulatory capacity which resulted in an increased IFN-gamma production. However, TNF-alpha treated DC, when administered in vivo, were shown to ameliorate disease in collagen induced arthritis, an experimental model of inflammatory joint disease. Mice receiving TNF-alpha treated DC but not LPS matured DC had a delayed onset, and significantly reduced severity, of arthritis. Disease suppression was associated with reduced levels of collagen specific IgG2a and decreased inflammatory cell infiltration into affected joints. In summary the treatment of DC with TNF-alpha generates an antigen presenting cell with a phenotype that can reduce the pro-inflammatory response and direct the immune system towards a disease modifying, anti-inflammatory state. |
| Authors | Louise J Healy, Helen L Collins, Stephen J Thompson
(Affiliation: Division of Immunology, Infection and Inflammatory Diseases, King's College London, London, UK.)
|
| Journal | The open rheumatology journal
(Open Rheumatol J)
Vol. 2
Pg. 71-80
( 2008)
ISSN: 1874-3129 Netherlands |
| PMID | 19156221
(Publication Type: Journal Article)
|
