NK killing of infected thyrocytes.

<p>Cytotoxic activity associated with NK cell activation was analyzed in PBMCs from 3 controls and 3 HT patients. Nthy-ori3-1 cells at optimal density were infected with HHV-6 and cocultured with freshly isolated PBMCs at 48 hours post infection. After 4 hours of coculture, induction of apoptosis was evaluated by flow cytometry after staining with FITC-labeled Annexin-V, and cell viability was assessed by Propidium Iodide (<b>A, C</b>). In parallel, degranulation was assessed by staining with PE-Cy5-conjugated anti-CD107a mAb and gating on CD3−/CD56+ NK cells (<b>B, D</b>). NK degranulation <i>vs</i> K562 is also shown, as a positive control for standard cytotoxic assay. Results were obtained in triplicate samples. (<b>A, B</b>) Control subject, respectively induction of apoptosis (<i>left</i>) and degranulation (<i>right</i>) panels. (<b>C, D</b>) HT patients, respectively induction of apoptosis (<i>left</i>) and degranulation (<i>right</i>) panels. Results are representative for three independent experiments performed on PBMC from different HT and control subjects.