Establishment and Characterization of α s1 -Casein-Specific T Cell Lines from Milk-Allergic Patients

αs1-casein has been found to be one of the major allergens in bovine milk. We isolated 28 αs1-casein-specific T cell lines (TCLs) from 4 milk-allergic patients and characterized their epitope specificites and functions. Stimulation of these αs1-casein-specific TCLs with sequential peptides of αs1-casein revealed the determinants recognized by 5 TCLs. They each reacted to different peptides. In response to αs1-casein, some of them secreted both interleukin 4 (IL-4) and interferon (IFN) -γ, some either IL-4 or IFN-γ only, and the others neither of the two cytokines.