First six images are of the interaction, and will be published in the Blood manuscript with the reconstruction. The last one is an aligned average, showing the virus, membrane and fibre attaching. The images are of Ad5 interacting with erythrocyte ghost membranes via its fibre that projects from the fivefold vertex represent the stage in virus-membrane interaction prior to the one reconstructed in the deposited map. The interaction is via the coxsackie-adenovirus receptor (CAR), which binds to the end of the fibre. The main focus of the manuscript describing this work was the demonstration that CAR is found on human erythrocytes, along with complement receptor 1 (CR1) and that this has major implications for the use of Ad5 as a vector in immunisation.