|
|
||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||


*Laboratory of Neuroimmunology, Department of Neurology and the Agnes Ginges Center for Human Neurogenetics, Hadassah-Hebrew University Medical Center, Jerusalem, Israel;
The Genetic Institute, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel; and
Department of Pathology and Laboratory of Medicine, Weill Medical College, Cornell University and New York Presbyterian Hospital, New York, NY 10065
The
7 nicotinic acetylcholine receptor (nAChR) was recently described as an anti-inflammatory target in both macrophages and T cells. Its expression by immune cells may explain the epidemiological data claiming a negative link between cigarette smoking and several inflammatory diseases. In this study, we determined the immunological effects of
7 nAChR activation by nicotine. Our results indicate that the
7 nAChR is expressed on the surface of CD4+ T cells and that this expression is up-regulated upon immune activation. Nicotine reduced T cell proliferation in response to an encephalitogenic Ag, as well as the production of Th1 (TNF-
and IFN-
) and Th17 cytokines (IL-17, IL-17F, IL-21, and IL-22). IL-4 production was increased in the same setting. Attenuation of the Th1 and Th17 lineages was accompanied by reduced T-bet (50%) and increased GATA-3 (350%) expression. Overall, nicotine induced a shift to the Th2 lineage. However,
7–/–-derived T cells were unaffected by nicotine. Furthermore, nicotine reduced NF-
B-mediated transcription as measured by IL-2 and I
B transcription. In vivo, administration of nicotine (2 mg/kg s.c.) suppressed the severity of CD4+ T cell-mediated disease experimental autoimmune encephalomyelitis.
7–/– mice were refractory to nicotine treatment, although disease severity in those animals was reduced, due to impairment in Ag presentation. Accordingly, CD4+ and CD11b+ cells infiltration into the CNS, demyelination, and axonal loss were reduced. Our data implicate a role for the
7 nAChR in immune modulation and suggest that
7 nAChR agonists may be effective in the treatment of inflammatory disorders.
1 Address correspondence and reprint requests to Dr. Talma Brenner, Laboratory of Neuroimmunology, Department of Neurology, Hadassah-Hebrew University Medical Center, P.O. Box 12000, Jerusalem, Israel. E-mail address: brenner{at}cc.huji.ac.il
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |