A small immunogenic protein (M.W. 11,500) has been isolated from pooled calf corneal epithelia through the combined use of chromatography on small columns of 75 A controlled-pore glass beads coupled with ammonium sulfate and sodium sulfate salt fractionation. The antigenic material thus prepared failed to enter a 6.5% polyacrylamide gel and upon electrophoresis and was tentatively concluded to exist in the form of a calcium aggregate based on analysis by atomic absorption spectrophotometry. Addition of 0.001M EDTA to the immunogenic fraction prior to gel electrophoresis resulted in the release of the immunogenic protein from the aggregate into the gel so that it could be isolated from polyacrylamide for further analysis.