Murine anti-lymphocyte monoclonal antibodies fail to act as opsonins for allogeneic human peripheral blood...

Seven murine monoclonal antibodies (MoAbs) to antigenic determinants present on human lymphocytes did not promote phagocytosis of allogeneic human lymphocytes by human peripheral blood polymorphonuclear leucocytes (PML). Similarly there was no significant metabolic activation of PML as determined by incorporation of radiolabelled iodide. The opsonic activity of MoAbs was not enhanced by addition of human or rabbit complement nor by the use of sheep anti-mouse IgG, rabbit anti-mouse immunoglobulin or goat anti-mouse immunoglobulin as second antibody. Whole serum from mice immunized with human lymphocytes did not act as an opsonin when tested with human PML. Hyperimmune mouse antiserum to Bordetella pertussis antigen acted only weakly as an opsonin. Human PML may not have an in vivo role in the removal of allogeneic lymphocytes treated with murine anti-lymphocyte MoAbs.