Abstract Human placental laminin purified without the use of proteases promotes similar levels of cell attachment ? murine EHS laminin. The major HT1080 cell binding site of human placental laminin is thermally less labile than that of EHS laminin. Monoclonal antibody GOH3, which recognises the integrin α6 subunit, inhibits HT1080 and B16 cell attachment to EHS laminin but not to human placental laminin, indicating that the cells use different receptors to bind to these two types of laminin. Antibodies P1E6 and P1B5, which recognise the integrin α2 and α3 subunits respectively, do not affect HT1080 cell binding to either type of laminin.