ESTABLISHMENT AND CHARACTERIZATION OF ALPHA(S1)-CASEIN-SPECIFIC T-CELL LINES FROM PATIENTS ALLERGIC TO COWS MILK - UNEXPECTED HIGHER FREQUENCY OF CD8(-CELL LINES() T)

To study cow's milk allergy at the cellular level, we assessed the rea ctivity of peripheral blood mononuclear cells from patients allergic t o cow's milk to alpha(s1)-casein, which is one of the major allergens in cow's milk. Proliferation of the cells to alpha(s1)-casein activati on showed a rather weak response. Therefore to understand T-cell react ivity to alpha(s1)-casein in more detail we prepared alpha(s1)-casein- specific T-cell lines from patients allergic to cow's milk and establi shed 26 T-cell lines. These T-cell lines could be classified into thre e groups by analyzing their surface marker expression: those containin g predominantly CD4(+)CD8(-) T cells, those containing both CD4(+)CD8( -) and CD4(-)CD8(+) T cells, and those containing predominantly CD4(-) CD8(+) T cells. The CD8(+) T cells were obtained at an unexpectedly hi gher frequency from the patients. These T-cell lines produced interfer on-gamma and IL-4. These results suggest that CD8(+) T cells specific for alpha(s1)-casein and CD4(+) T cells were primed by the stimulation with alpha(s1)-casein in patients allergic to milk and that both T ce lls may play a key role in the onset, progression of, or recovery from cow's milk allergy.