Messenger RNA expression of TLR2 and TLR4 in CD3+CD4+CD28null and CD3+CD4+CD28+ T cells. (a) Fluorescence-activated cell sorting analysis shows the purity of CD3+CD4+CD28null and CD3+CD4+CD28+ T cells. (b) mRNA expression of TLR2, TLR4 and β2-microglobulin (β2m, housekeeping gene) in CD3+CD4+CD28null T cells (CD28-) and in CD3+CD4+CD28+ T cells (CD28+). Peripheral blood mononuclear cells were used as positive control (pos co), and a negative control (neg co) was performed in the absence of cDNA. A representative example out of three independent experiments is given.