In contrast, IL-17A- and IL-22-secreting cells were more abundantly derived Selleckchem GS-1101 from lesional skin (Supporting Information

Fig. S3B). This observation led us to use such lesions as a source of T cells to generate CD4+ T-cell clones with various Th profiles, including Th17 and Th22 cells. Hierarchical cluster analysis performed on the cytokine pattern of skin-infiltrating T-cell clones obtained from two psoriasis patients yielded distance trees that highlighted their organization into five dominant groups, each characterized by a typical cytokine secretion profile (Fig. 3A and Supporting Information Fig. S4A). The number of clusters obtained was validated using the non-hierarchical cluster analysis (data not shown) with an excellent inter-classification comparison index (kappa agreement value κ=0.89 and 0.70 respectively). The inter-cluster differences were confirmed through the computation of the mean relative cytokine productions in each proposed cluster, followed by inter-cluster comparisons (Fig. 3B and Supporting Information Fig. S4B).

This analysis confirmed that IFN-γ was most increased in the first cluster, as compared with other clusters (p<0.0001 for both patients), IL-10 in the second cluster (p<0.0001), IL-4 (p=0.001 and p=0.0065, 1st and 2nd patient respectively) and IL-5 (p<0.0001) in the third, IL-17 selleck chemical in the fourth (p<0.0001) and IL-22 in the fifth (p<0.0001) (Fig. 3B and Supporting Information Fig. S4B). The clusters were therefore named Th1, Tr1, Th2, Th17 and Th22 respectively. Altogether, these data suggest that Th1, Th2, Tr1, Th17 and Th22 orientation can be

objectively distinguished by cluster analysis of cytokine production profiles. The Th22 subset should therefore clearly be distinguished from the previously recognized Th17 subset. We then used TCRα and TCRβ clonotypic analysis to assess whether the commitment however of these functionally distinct subsets of CD4+ T cells would be antigen-driven or TCR-independent. Surprisingly, only 45 different clonotypes were used by the 66 T-cell clones derived from the skin biopsy of a psoriasis patient. Eight different clonotypes were extensively shared between subsets and represented 39% of the T-cell infiltrate (Fig. 4). One clone was shared by four different subsets. TCR sharing between the Th17 and Th22 subset, with only one clone shared, was not more extensive than that between other subsets. TCR sharing between functionally distinct T-cell clones was confirmed in a skin biopsy from a second psoriasis patient. In this case, TCR sharing was less extensive, but clones overlapping between Th17 and Th22 as well as Th17 and Th2 were nonetheless identified among the 59 skin-derived T-cell clones analyzed (Supporting Information Fig. S4C). These results demonstrate that none of the five Th cell types use a strictly dedicated TCR repertoire.