We studied 8 soft contact lenses from asymptomatic wearers by means of an immuno-cytochemical method, in transmission electron microscopy. In particular, the presence of IgA, IgG, IgE, C1qcomplement fraction within the surface deposits was analyzed.All the lenses were found positive for the immunoglobulins and the C1q, being the tarsal side more heavily coated than the corneal one. IgA was the predominant Ig, followed by IgG, IgE, and C1qin this descending order. New, never worn lenses were found completely negative for any of the proteins under investigation.We conclude that the Igs come from the tear fluid and speculate about the C1qas a possible sign of involvement of the host immuno-defense mechanism against the prosthesis.