Lysozyme penetration in group IV soft contact lenses.
OBJECTIVE
To establish proper contact lens care as a common practice by discovering the quantity and condition of protein deposition on various types of soft contact lenses.


METHODS
The amounts of deposition of two proteins found in tear fluid, lysozyme and albumin, on various types of contact lenses were measured. Lenses deposited with albumin and lenses deposited with lysozyme were stained with Coomassie brilliant blue (CBB). Frozen cross-sections of these lenses were examined using a microscope.


RESULTS
A considerably larger amount of lysozyme was found on group IV (U.S. Food and Drug Administration classification) contact lenses. Conversely, there were no significant differences between the four groups in the quantity of albumin found. When various lenses were stained with CBB, only the lysozyme-deposited lenses of group IV obtained a strong tint. When cross-sections of the tinted group IV contact lenses were examined, not only the surface, but also the matrix of the lens was stained.


CONCLUSIONS
Results suggested that the reason group IV lenses accumulated a considerably greater amount of lysozyme than did lenses of other groups is that lysozyme accumulates not only on the surface, but also in the matrix of group IV lenses.
Okada
Eiichi
E
Okada Eye Clinic, Yokohama City University School of Medicine, Yokohama, Japan. toukai@titan.ocn.ne.jp
Matsuda
Tomoko
T
Yokoyama
Tetsuro
T
Okuda
Kenji
K
D000418:Albumins / Q000032:analysis; D003263:Contact Lenses, Hydrophilic; D005136:Eye Proteins / Q000032:analysis*; D066298:In Vitro Techniques; D007202:Indicators and Reagents / Q000494:pharmacology; D009113:Muramidase / Q000032:analysis*; D012394:Rosaniline Dyes; D013194:Staining and Labeling / Q000379:methods
D000418:Albumins; D005136:Eye Proteins; D007202:Indicators and Reagents; D012394:Rosaniline Dyes; C042434:tear proteins; C048139:Coomassie blue; D009113:Muramidase