Lymphocyte-facilitated tumour cell adhesion to endothelial cells: the role of high affinity leucocyte integrins.

Aim: Lymphocytes transiently express an active form of the beta_2 integrin LFA-1 (LFA-1Af) which has conformational changes in extracellular domains enabling higher affinity binding to the ligand ICAM-1. In this study, we investigated the role of lymphocytes bearing LFA-1Af as potential mediators of binding of ICAM-1-positive tumour cells to endothelium.

Methods: LFA-1 expression on 51Cr-PBLs was modulated in order to express high affinity LFA-1Af and conjugates were formed with 35S-labelled COLO526.