Figure 2.

Anti–citrullinated cytokeratin 13 (anti–cCK13‐1) antibody cross‐reactivity with citrullinated tenascin‐C (cTNC5), citrullinated fibrinogen β (cFIBβ), citrullinated α‐enolase peptide 1 (CEP‐1), and citrullinated vimentin (cVIM). Serum from patients positive for both anti–cCK13‐1 and the test antibodies were preincubated with increasing concentrations of the indicated test peptide, and the IgG responses to cCK13‐1 were measured by enzyme‐linked immunosorbent assay and presented as the OD. Each symbol represents an individual patient.