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Maria Lexberg, Hyun-Dong Chang, Andreas Radbruch
Stability and plasticity of IL-17 producing T cells
Maria Lexberg, Hyun-Dong Chang, Andreas Radbruch
Deutsches Rheumaforschungszentrum, Berlin
Chariteplatz 1
10117 Berlin
Germany
Tel +49-30-28460-600/667
radbruch@drfz.de
lexberg@drfz.de
Classically, effector memory CD4 T cells are divided into distinct lineages on the basis of
their cytokine production profile and the resulting effector function. Recently, a novel
lineage of CD4 T cells has been described which is characterised by the production of IL-
17. These cells have been termed Th17 cells. In several reports, this lineage has been
allocated a role in autoimmune inflammation, therefore it is of importance to determine
the stability of its expression and how it could be modulated to attenuate disease
symptoms.
Our aim is to analyse the induction and maintenance of a functional cytokine memory of
Th17 cells. We are investigating the plasticity and stability of IL-17 memory expression
in relation to the cytokine memory expression of the other lineages.
Both Th1 and Th2 cells proved refractory to IL-17 induction and maintained their
phenotype when stimulated under Th17 inducing conditions in the presence of TGF-beta
and IL-6. To test the stability and plasticity of Th17 cells, we cultured Th17 cells under
Th1 and Th2 inducing conditions and measured cytokine expression. The frequency of
IL-17 expressing cells observed in one or four week old Th17 cells was reduced when
restimulated for just one week in the presence of IL-12 or IL-4, although the
reexpression of IL-17 was increasingly stabilized depending on the duration of
polarization. The plastic nature of IL-17 expression in Th cells reveals that Th17 cells
may need a certain environment in vivo to maintain IL-17 expression and are prone to
regulation by both Th1 and Th2 cells.