Ocular lesions in experimental Trypanosoma brucei infection in cats.

Experimental Trypanosoma brucei-infection progressing clinically peak-wise, induces intense proteinleakage in the anterior chamber of cats' and dogs' eyes, with a cyclitislike symptomatology, preceded by hypersensitivity of conjunctiva and respiratory mucosae, together with lacrimation, and facial oedema. The pherogram of aqueous humor is the replica of the serumpherogram at the endstage of the disease and is identical to secondary aqueous. Absence of any significant changes in serumproteins, immunoglobulins and the poor cellular reaction at tissue-level point towards immune unresponsiveness subsequent to experimental protozoal infection. Light-microscopy reveals at the level of the ciliary processes two kinds of cystic formation, the walls of which are formed by ciliary epithelium. One type contains amorphous material next to trypanosomes, macrophages and plasmocyte-like cells; the second type contains also fibrillar structures possibly reminding collagen. Ultramicroscopy suggests these cystic formation to be enlarged ciliary channels. The fenestrated capillary wall showing no changes neither after withdrawal of aqueous, nor after toxic parasite-action, the presence of large proteinmolecules and trypanosomes in the anterior chamber are due to damage to the ciliary epithelium.