Bacterial binding to immobilized Fg. Microtiter wells were coated with fibrinogen at the concentration indicated and blocked with BSA. Adherence was allowed for 2 h, microtiter plates were washed and dried, and relative bacterial adherence was determined spectrophotometrically (A405). □, S. aureus Newman; ○, S. epidermidis 2; ▪, S. epidermidis 19; ▵, S. epidermidis 269; •, S. epidermidis 333; ▴ S. epidermidis HB.