Immunoglobulins were found in all structures of the eye except the lens. The highest concentrations (up to one-half the amount in serum) were found in the cornea, choroid, and conjunctiva. Moderate concentrations were found in the muscle and sclera. Low concentrations (less than 5% of the serum level) were found in the ciliary body, iris, aqueous, and retina. All five immunoglobulins and albumin were present in the immunoglobulin-containing tissues except for the cornea, which did not routinely contain IgM.
Allansmith MR, Whitney CR, McClellan BH, Newman LP. Immunoglobulins in the Human EyeLocation, Type, and Amount. Arch Ophthalmol. 1973;89(1):36-45. doi:10.1001/archopht.1973.01000040038010