Network analysis of global proteomic data from liver samples of HCV-positive patients. We constructed association networks from proteomics as described in the text, varying parameters as indicated in (Additional file 5: Table S3). The top 20% of proteins ranked by the topological degree (blue diamonds), betweenness (red squares), clustering coefficient (green diamonds), and closeness (purple circles) were evaluated for their enrichment in proteins that are pathogen interactors. Fold enrichment (Y axis) is calculated as the percentage of pathogen interactors in the group divided by the percentage not in the group. Statistical significance is indicated in (Additional file 5: Table S3).