Long-term T-cell lines from the tears of patients with vernal conjunctivitis

Previous studies of the tears and conjunctival tissue of vernal conjunctivitis (VC) have suggested that cellular immune mechanisms may be important in the inflammatory process of this ocular disease. However, little information is available in support of a cell-mediated immune mechanism because of the difficulty of tissue access and the small numbers of mononuclear cells in the tear secretions. Tear secretions of VC patients contain few lymphocytes (estimated 10³ per 300 μl of tears). Tear lymphocytes from 5 of 7 VC patients were propagated in culture in the presence of interleukin 2. In 2 months of culture the tear lymphocytes were expanded to 5 x 10⁶-10⁷ cells. Phenotyping studies with monoclonal antibodies showed that all cell lines exhibited T-cell markers. In 2 of 3 tear specimens which were initially cultured in the presence of the putative specific antigen, i.e. rye grass or ragweed antigen E, the OKT4 helper/inducer phenotype predominated while the cell lines without antigen exhibited mostly the OKT8 phenotypes. These studies demonstrated the feasibility of generating long-term IL-2 dependent T-cell lines from the tear secretions of patients with VC which will enable the study of localized cellular immune processes in external ocular disease.