Tears from normal (n = 5) and serum IgA deficient (n = 3) individuals were investigated for the presence of secretory Immunoglobulin A (sIgA), sIgM and free secretory component (SC) by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) using 10-15% gradient minigels (PhastSystem), followed by immunoblotting using various immunological probes. Tear samples were treated in denaturing (SDS) sample buffer under non-reducing as well as reducing conditions, prior to analysis. All normal tear samples contained sIgA as well as free SC (estimated MW: 82kD) but only traces of IgM. Tears from the three serum IgA deficient subjects lacked sIgA but did contain free SC. In two of them sIgM was clearly detected and after treatment of tears with reducing agent, IgM (mu) heavy chain fragments (estimated MW: 78kD) were identified and could be distinguished from other tear proteins after SDS-PAGE. These findings indicate lacrimal secretion of free secretory component, even in the absence of its ligand. On the ocular surface, sIgM may play a compensatory role in IgA deficiency.

In order to evaluate the anti-inflammatory effect of non-steroidal compounds on the eye, we tested them in rabbits using the inhibitory effect on paracentesis-induced disruption of the blood-aqueous barrier. Protein and – after intravenous-injection – fluorescein were determined in punctates of aqueous humor. Indomethacin, fluorbiprofen and diclofenac in a 0.01% solution showed a marked inhibitory effect, which lasted for 24 h. Addition of polysorbate to eye drugs diminished the inhibitory effect.