Abstract
Purpose: :
Mucin turnover at the ocular surface is not fully understood. Blinking, bacteria and adherence to contact lenses are expected to contribute to mucin degradation and removal. We analyzed mucins adhering to two types of contact lenses worn in sequence, to assess whether a new lens provides new opportunities for mucin fragmentation.
Methods: :
Contact lenses were obtained from new contact lens wearers after 2 weeks each of wearing Vifilcon A lenses, followed by Senofilcon A, followed by Vifilcon A lenses. All lenses were extracted in a mixture of GuHCl and RIPA buffer. Mucin mobility was analyzed after electrophoresis on 4-12% Nupage gels with MES buffer, western blotting and visualization with antibodies against mucin peptide core. Intensities were plotted along each lane, representing mobility respective to molecular weight markers in each gel.
Results: :
Mucins adhering to both contact lens types were polydispersed in size. MUC5AC polymers exceeding 260kDa were observed in agarose gels. NuPage resolved polymers from 260 to 3.5kDa. When large mucins were detected the smallest fragments, under 15KDa, were missing. For the same individual, larger MUC5AC and MUC1 species were detected on Senofilcon A lenses, while patterns on the two Vifilcon A lenses were very similar. MUC16 fragmentation, however, was not similar on both lens tyes.
Conclusions: :
Differences in mucin polymer sizes are unlikely to follow from differential adhesion to the contact lens, suggesting that wear of a different contact lenses triggers a change in ocular flora, resulting in a new pattern of mucin fragmentation.
Keywords: contact lens • glycoconjugates/glycoproteins • cornea: tears/tear film/dry eye