Whole-blood culture
Whole blood cells (500 µL of blood) were incubated with 20 μg/ml
concanavalin A (Con A, Sigma-Aldrich, St. Louis, MO, USA) at 37°C under
5% CO2 for 24 hours using 48-well plates (Corning Inc.,
Corning, NY, USA). Collected culture supernatants were assayed for IFN-γ
by Bovine IFN-γ ELISA Development Kit (Mabtech, Nacka Strand, Sweden)
according to the manufacturer’s instructions.