Table 1 Evidence for assessing the suitability of tear proteins for clinical use
From: Practical issues concerning tear protein assays in dry eye
| Class of tear protein | Potential clinical marker | Human tear levels show consistent dysregulation | Human tear levels linked to clinical signs/symptoms of dry eye | Change with treatment or severity of dry eye? | Biological function in dry eye pathology known? |
|---|---|---|---|---|---|
| Lacrimal protein | Lactoferrin | ++++ [21]-[25] | +++ [26],[27] | + [28] | ++ [29] |
| Protease | MMP-9 | +++ [30]-[32] | +++ [11] | +++ [33] | +++ [34]-[42] |
| Lacrimal protein | Lysozyme | ++ [21],[43]-[45] | + [43] | 0 | 0 |
| Mucins | MUC5AC | +++ [46],[47] | + [48] | 0 | ++ [49],[50] |
| Lipid binding protein | Lipocalin | ++ [45],[51] | + [52] | ++ [52] | + [53]-[55] |
| Interleukines | IL-6 | +++ [10],[31],[56],[57] | + [58] | ++ [58] | + [59]-[61] |
| Chemokine | IL-8 | ++ [10],[57],[62],[63] | ++ [62] | 0 | ++ [61],[64] |
| Keratinisation-related | S100A8/9 | +++ [5],[13],[14],[65] | +++ [5],[13] | 0 | + [66],[67] |
| Epithelial health | EGF | ++ [57],[64],[68] | + [69] | 0 | ++ [70] |
| Neurotrophic health | NGF | +++ [71],[72] | ++ [71],[73],[74] | ++ [73],[74] | ++ [75],[76] |