In vitro–polarized effector CD4⁺ T-cell subsets acquire distinct phenotypes and gene expression profiles. (A) In vitro polarizing conditions alter the phenotype of TRP-1 cells. Th0, Th1, and Th17 TRP-1 T cell were analyzed using flow cytometry for the expression of selected activation markers and adhesion molecules: CD62L, CD45RB, SCA1 (Ly6a), CD38, and CD49d (integrin α4, VLA-4). Percentage of positive cells is calculated based on the comparison with an isotype control antibody. (B) Relative alterations in mRNA quantities of selected genes are observed using microarray analysis. Th1 versus Th17 TRP-1 cells were compared, using Th0 mRNA as a reference. mRNAs are grouped by their function (integrins and adhesion molecules, matrix metalloproteinases [MMPs] and related molecules, cytokines and their receptors, chemokines, and chemokine receptors). A cutoff for significant difference in the level of mRNA message expression was set at 2-fold.