SPP1 and type 2 diabetes mellitus: In current study, the events occurring during the 16 weeks observation of T2D that could provide necessary triggers include: (1) the gradual accumulation of OPN on the ocular surface and in tear fluid, (2) destabilization of tear fluid resulting in an accumulation of proinflammatory mediators such as IL-6, TNF-α, and MMP-9, and/or the loss of critical protective factors like IL-10 that modulate corneal inflammation, and (3) changes in tear fluid Na+ levels that allow the accumulation of microbial triggers contributing to ocular surface irregularity.