PIP and diabetes mellitus: At the same time, the level of proteins such as Znα2-glycoprotein, prolactin inducible protein, lysozyme-C, lipophylin A, lipocalin-1, lactotransferrin, extracellular glycoprotein lacritin, Ig λ chain C region, galectin 3-binding protein and dermcidin having a role in the host defense was analyzed by SRM-based relative quantification in the tears of healthy controls and patients with DM and DR.