Background Blockade of lymphocyte function associated antigen‐1 (LFA‐1) is proving successful in the management of psoriasis and other inflammatory skin conditions including atopic dermatitis (AD), but the dependence of allergen‐specific CD4+ T‐cell function on LFA‐1 has not been studied extensively. Objectives We sought to investigate the potential ability of LFA‐1 inhibition to influence keratinocyte presentation of allergen to specific T‐helper (Th) 2 cell clones. Methods Using human leucocyte antigen class II tetrameric complexes, we generated Der p 1‐specific DRB1*1501‐restricted CD4+ T‐cell lines (n =5) and clones (n =4) from the peripheral blood of five adults with AD. Results Using doses of anti‐LFA‐1 present in vivo, we observed significant inhibition (P <0·05) of allergen‐specific CD4+ T‐cell production of interleukin‐4 with such inhibition occurring during presentation of allergen by keratinocytes. Conclusions These data show that at doses present in vivo, LFA‐1 blockade inhibits keratinocyte presentation to allergen‐specific Th2 cells, suggesting one mechanism through which anti‐LFA‐1 may be beneficial therapeutically. |