Fig 4. Cytokeratin (CK) 13 in the saliva of patients with rheumatoid arthritis (RA) and healthy participants.

Twelve microliters of saliva per lane were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A: Immunostaining was performed using an anti-CK13 antibody as the primary antibody and horseradish peroxidase-conjugated goat anti-rabbit IgG antibody as the secondary antibody. Lane P: positive control (recombinant CK13), Lanes 1–5: saliva from patients with RA; Lanes 6–11: saliva from healthy participants. B: Immunostaining was performed using only HRPO-conjugated goat anti-rabbit IgG antibody without primary antibody. Lane 1: Saliva from a healthy individual.