Siglec-9 interacts with VAP-1. (A) The amino acid sequence of the enriched phage clone, the corresponding region of Siglec-9, and the adhesion of the phage peptide to recombinant VAP-1 (rVAP-1 100 ng/well) were measured using enzyme immunoassay. The results are mean ± SEM from 3 separate experiments and triplicate wells in each experiment. (B) Binding of the Siglec-9 peptide (Sig-9 pept marked red in panel A) to CHO-VAP-1 transfectants and CHO-mock controls. The results are presented as relative fluorescence intensity and are mean ± SEM from 2 separate experiments each having triplicate wells. (C) Binding of CFSE-labeled Siglec-9 transfectants to CHO cells expressing VAP-1 and mock controls. The results are mean ± SEM of fluorescent intensities measured by fluorometer from 7 separate experiments each having duplicate wells. **P < .01. ***P < .001.