This extract is capable of inducing blastogenesis in vitro in various mammalian mononuclear cells when used at a concentration of 1–2% v/v. Each lot of Gibco™ Phytohemagglutinin is performance tested at 1.5% using peripheral blood lymphocytes from a normal adult donor cultured for 72 hours in Gibco™ RPMI 1640 Medium supplemented with Fetal Bovine Serum (FBS), heparin, antibiotics, and L-glutamine.