tokens: Cells were subsequently stimulated with 1 ) PMA for 24 h , inducing CAT activity by 2.6-fold , 2 ) fibrinogen /Mn2+ for 2 h , inducing CAT activity by 3.2-fold , or 3 ) costimulation with fibrinogen and PMA , inducing 5.7-fold the CAT activity induced by PMA alone .