It is noteworthy to stress that while PAS and muc5AC were tested as clear indicators of diagnosis/prognosis/monitoring, AP and total RNA/protein analysis had the purpose to validate the sampling procedure, providing information on the cellular processes of sampled epithelia, as measurement of lysosomal enzyme activity inside the cornea/conjunctiva; in fact AP is not an indicator of pathological state. Here, MUC5AC is linked to alkaline phosphatase measurement.