FN1 and infection: No signal over background levels (OD450 = 0.1; intrinsic to the phage ELISA) was detected in control wells incubated with Ff-nano particles that did not display FnB, derived from the infection with vector Rnano3 (without the FnB domain) nor in the wells coated with BSA only (from which fibronectin was omitted; Figure 4B), apart from the full-length Rnano3 particles (not displaying FnB) which gave a low signal OD450 = 0.3 in the presence of Fn.