TOXOPLASMA GONDII-SPECIFIC ANTIBODIES IN THE AQUEOUS-HUMOR OF CATS WITH TOXOPLASMOSIS

We decided to determine whether Toxoplasma gondii-specific IgM or IgG is produced locally or is deposited in the aqueous humor of T gondii-n aive cats after primary or secondary inoculation with T gondii. Cats w ere orally inoculated with T gondii tissue cysts during weeks 0 and 36 . Aqueous humor and serum T gondii-specific IgM and IgG were measured, using ELISA, during weeks 0, 2, 4, 6, 8, 12, 16, 20, 26, 34, 38, 40, 42, 44, 48, 56, 62, 66, and 72 after primary oral inoculation. Total i mmunoglobulin-based Goldmann-Witmer coefficients were calculated to ve rify intraocular antibody production. Toxoplasma gondii-specific IgM w as not detected in the aqueous humor of any cat. Data indicate that ca ts have transient local production of T gondii-specific IgG in the aqu eous humor after primary and secondary oral inoculations with T gondii tissue cysts. The intraocular immune response to systemic T gondii in fection may signal ocular recruitment of antigen-specific lymphocytes that function independently from the general humoral response to T gon dii infection. Cautious interpretation of results that suggest intraoc ular production of T gondii-specific IgG in cats with uveitis is warra nted.