[Ultrastructural study of the adsorption of lymphocytes on cells infected by vacinnia virus]

Adsorption of chicken lymphocytes to HEp-2 cells infected with vaccinia virus was found to occur by two processes. In one, the lymphocytes were attached to the microvilli of the HEp-2 cells, and the lymphocyte and host cell were separated at a distance of up to 0.6 micron. In the other, there was direct and close binding of the lymphocytes to the infected HEp-2 cell. The lymphocyte and HEp-2 cell were separated by an apparent gap approximately 10 to 20 nm in width.