Phage attachment assay. Purified phage clones were incubated in microtiter plates coated with PMN freshly isolated from peripheral venous blood. Bound phage were detected with polyclonal anti-phage antibody and quantified by light absorbance as described in Materials and Methods. (A) Distinct PMN binding phage clones selected from different experiments. The DLVTSKLQV phage consistently showed a weaker detection signal as compared with the other binding phage. (B) The binding affinity of phage clones displaying different grades of homology to the consensus motif DLXTSK(M/L)X(V/I/L). Compared with the DLVTSKLQV-displaying phage, clones with fewer residues matching to the consensus motif show a decreased binding affinity. Control phage displayed irrelevant sequences (AQPQVRPIG or GPRPGPPKL). Optical density at 405 represents phage incubated wells after subtraction of the wells without phage incubation. Phage clones incubated on BSA coated wells (not shown) yielded OD value between 0.1 and 0.2. Values representative of one of two experiments showing the mean ± SD of quadruplicate determinations.