“…There is increasing recognition that exogenously administered antibody may exert a therapeutic effect by redirecting the host response rather than by playing a purely passive role (16,18,26,45,53,55,56,84,90,93,100,114,129). Both polyclonal and monoclonal reagents, administered either alone or in combination with antigen, have been used to up-regulate beneficial or protective immune responses against infectious agents and malignant tumors as well as to down-regulate deleterious responses associated with inflammation, autoimmunity, and hypersensitivity (8,55,57,58,84,102,110). In light of a growing body of literature, the practicality of employing preformed antibody to manipulate an immune response toward a desired end is becoming more apparent and will broaden the strategies for active and passive immunization approaches against infectious disease.…”