Palmitate-derivatized antibodies can function as surrogate receptors for mediating specific cell-cell interactions

The observation that exogenously supplied agents can bypass intrinsic recognition mechanisms and facilitate cellular conjugation has led to valuable insights into the mechanisms of cell function. A common feature of currently available cellular conjugation agents is their reliance on endogenous membrane molecules on both cell types as anchors for cellular interactions. In this report, we describe a method for incorporating palmitate-derivatized antibody molecules onto cell membranes where they function as 'surrogate receptors' (SR) for mediating specific cellular interactions. In this system, SR are attached to the plasma membrane by insertion of the palmitate hydrocarbon chains into the outer leaflet of the phospholipid bilayer. Therefore, the palmitate anchor bypasses the requirement for FcR or other endogenous membrane proteins in antibody-dependent cellular conjugation. Due to this mode of attachment, which is similar to that of phosphatidylinositol (PI) anchored proteins, SR-mediated cellular interactions are likely to be reminiscent of native receptor-induced conjugation, enabling SR to cooperate with endogenous target recognition structures in receptor-ligand interactions at the cell-cell interface.