Longer local retention of adoptively transferred T-LAK cells correlates with lesser adhesion molecule expression than NK-LAK cells.

The local retention of adoptively transferred lymphokine (IL-2)-activated killer (LAK) cells was examined in 11 patients with head and neck carcinoma. Unseparated lymphocytes, T and natural killer (NK) cells isolated from patients were cultured with IL-2 for 7 days, labelled with 99mTc-HMPAO, and immediately injected back into the respective donors via the superficial temporal artery or locally into the tumour tissue. The injected LAK cells were periodically traced using a gamma camera, and the LAK cell retention rate was calculated from the radioactivity. One hour after the injection, about 70% of the locally infiltrated LAK cells remained in the tumour tissue, while about half of the LAK cells transferred via the regional artery were dislodged from the tissue. LAK cells induced from T cells (T-LAK) were retained in the tissue for a longer time than LAK cells induced from NK cells (NK-LAK). T-LAK were less chemotactic and less adherent to human umbilical vein endothelial cells (EC), and showed lesser migration through EC. Flow cytometric analysis revealed higher expression of CD11a, CD11b, CD18 and CD49d on NK-LAK compared with T-LAK. MoAbs against these adhesion molecules suppressed adhesion and migration of LAK cells. These results indicate that the rapid disappearance of NK-LAK from the tissue is associated with their greater chemotactic and adhesive as well as migratory activities depending on differing expression of adhesion molecules.