The effect of MEL‐14, a monoclonal antibody which binds to the lymphocyte homing receptor (MEL‐14 Ag) on lymphocytes for peripheral lymph node (PLN) high endothelial venules (HEV), was investigated on lymphocyte migration into a delayed‐type hypersensitivity (DTH)‐like lesion produced by sensitization and challenge to Bordetella pertussis vaccine (BPV). Pretreatment of lymphocytes with saturating concentrations of MEL‐14 caused a highly significant inhibition of lymphocyte migration into the chronically inflamed site and PLN. This finding suggests that lymphocyte migration into the BPV‐induced site of chronic inflammation may be regulated by the same mechanism as lymphocyte migration into the PLN. It further indicates that the ligand for the MEL‐14 Ag adhesion molecule, recognized by lymphocyte which home to the PLN, may also be expressed on HEV‐like vessels at sites of BPV‐induced chronic inflammation.