Multi spot meso scale discovery kits

To determine the immune response to acute psychosocial stress 5–10 ml of whole blood was collected in EDTA tubes at 4 time-points throughout the TSST: time(t) −45, t+20, t+50, t+80 min. To determine the effect of exam-stress on immune function 10–15 ml of whole blood was collected in EDTA tubes during each study visit (Non-Stress/Exam Stress). Samples were centrifuged immediately at 1500×g for 10 min and aliquoted plasma samples were frozen at −80 °C until analysis. Plasma levels of IL-10, IL-1β, IL-6, IL-8, and TNF-α were assayed in duplicate using high sensitivity commercially available electrochemiluminescence MULTI-SPOT® Meso Scale Discovery kits (MSD, Rockville, MD, USA) as per manufacturer's instructions. The median lower limits of detection for each cytokine are IL-6- 0.06 pg/ml, IL-8- 0.04 pg/ml, TNF-α- 0.04 pg/ml and IFN-γ- 0.2 pg/ml.