Peptidomic analysis of human reflex tear fluid

► The peptidome of human reflex tear fluid was analyzed. ► Thirty endogenous peptides were identified by using off-line LC-MALDI-TOF-TOF. ► Twenty-six peptides are derived from proline-rich protein 4. ► Four peptides are derived from the polymeric immunoglobulin receptor. ► These peptides may contribute to the protective environment of the ocular surface.