Studies of the Proteins of Lacrimal Secretions

Abstract

Summary The major immunoglobulin of tears is IgA globulin, which is recovered in the external volume when subjected to Sephadex G 200 gel filtration. This protein contains “transport” or “secretory” piece as does the IgA globulin of other secretions. Another protein in tears, the anodal tear protein, is not related to albumin but is electrophoretically a “prealbumin.” It has gel filtration characteristics consistent with a molecular weight intermediate between that of serum albumin and of lysozyme, and has not been identified in serum, spinal fluid, saliva or urine. The protein content of tears shows an inverse relationship to the volume of lacrimal fluid obtained during a collection period of less than 5 min.