<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>Serum from blood that contains antibodies that bind to human T cells. Antithymocyte globulin is given to a patient before a stem cell transplant to kill T cells and lower the risk of graft-versus-host disease (GVHD). It is also used to treat GVHD and after a kidney transplant to help keep the body from rejecting the kidney.</n0:def-definition><n0:def-source>NCI-GLOSS</n0:def-source></n0:ComplexDefinition>
<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>A purified gamma immunoglobulin (IgG) with immunosuppressive activity. Obtained from animals that have been immunized with human thymocytes, antithymocyte globulin (ATG) specifically recognizes and destroys T lymphocytes. Although not completely understood, the mechanism of action appears to involve T lymphocyte clearance from the circulation and modulation of T lymphocyte activity. Administering ATG with chemotherapy prior to stem cell transplantation may reduce the risk of graft-versus-host (GVH) disease.</n0:def-definition><n0:def-source>NCI</n0:def-source></n0:ComplexDefinition>