APP and age-related macular degeneration: To this end, quantitative analysis of lactoferrin (LF), S100 calcium-binding protein A6 (S100A6), metallothionein 1A (MT1A), complement factor H (CFH), clusterin (CLU), amyloid precursor protein (APP), Mg, P, Na, Fe, Cu, Zn, and Ca have been carried out in low volume of tears from control subjects and patients diagnosed with the dry form of AMD.