Mucus is a secretion which contains a number of components of which mucins (glycoproteins of varying structure) are the entities mainly responsible for the physical properties of a visco-elastic gel. Technical problems which have previously hindered the elucidation of the chemical structure of these molecules have recently been overcome sufficiently to permit the development of structural models which explain both the common and variable features of mucus, healthy or pathological, in different sites of the body.
