Purpose. To determine whether the regulators of complement activation,
decay-accelerating factor (DAF) and CD59, which have been identified
on the cornea and conjunctiva and in soluble forms in tears and lacrim
al secretions, are transferred to soft contact lenses worn by normal s
ubjects. Methods. Following overnight wear of group 3 extended-wear hy
drophilic contact lenses by five normal subjects, we examined the lens
es immunohistochemically for decay-accelerating factor (DAF) and CD59,
two regulators which interfere with the complement cascade at the C3
and C9 steps, respectively. Results. Both proteins were detected on ai
l worn lenses but not on controls. Conclusions. These findings raise t
he question of whether these proteins, as do other contact lens-bound
proteins, have deleterious effects, or to the contrary, if they mainta
in their natural activity, might they have protective functions for co
ntact lens wearers.