The fluorescent antibody tissue stain for treponemes is described and its usefulness in experimental ocular syphilis documented. Two primates, inoculated by intraocular and intracisternal routes, respectively, acquired syphilis serologically but only one developed clinical lesions. The fluorescent antibody tissue stain (FA) demonstrated the presence of treponemes in aqueous humor from each animal. It was of interest that Treponema pallidum could be demonstrated in the aqueous humor of eyes that were virtually normal at the time of paracentesis. Further investigation of the FA stain in the diagnosis of syphilis is suggested.
Wells JA, Smith JL. The Fluorescent Antibody Tissue Stain in Experimental Ocular Syphilis. Arch Ophthalmol. 1967;77(4):530-535. doi:10.1001/archopht.1967.00980020532017