NKG2D and DAP10 mRNA levels are decreased in NK cells displaying a reduced surface expression of NKG2D. Real-time reverse transcription–polymerase chain reaction was performed on mRNA isolated from NK cells purified from mock- or TB40/E-treated PBMCs for 72 hours. (A) Surface NKG2D expression on NK cells was analyzed by flow cytometry in PBMC samples. Histograms correspond to the isotype controls (thin lines), mock-treated (gray profiles), and TB40/E-infected (bold lines) samples from 1 representative donor. (B) Bar graphs indicate the expression levels of the NKG2D and DAP10 transcripts. The endogenous control glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used to internally standardize the levels of gene expression. Data are expressed as fold difference between mock-treated cells (whose levels of gene expression have been assumed as 1) and cells cultured in the presence of TB40/E. Bar graphs include results obtained with NK cells derived from 3 different donors (mean ± SD). Statistical significance (2-sided Mann-Whitney test) is shown; *P < .05.