title: Monitoring anti-thymocyte globulin (ATG) in bone marrow recipients.
abstract: The present study was undertaken to acquire a rationale for clinical dose adjustment of anti-thymocyte globulin (ATG) to improve cost effectiveness and safety of graft-versus-host disease prophylaxis. The concentration of rabbit ATG in the serum of 12 patients was measured by ELISA and by the inhibitory effect on phytohaemagglutinin-induced blastogenesis. At 10 mg/ml ATG, 3H-thymidine incorporation was effectively blocked. Serial two-fold dilution of ATG showed that this effect decreased in a concentration-dependent manner and was lost at 10 ng/ml ATG. One hundred microlitres serum taken at day -1 to +22 post transplant effected significant inhibition of the phytohaemagglutinin-response with 49+/-12% c.p.m. (x +/- s.d.) on day +1 post transplant compared to 93+/-13% c.p.m. on day -1 (P<0.001, unpaired one-sided t-test). The rabbit-IgG was maximal at a concentration of 907+/-187 microl/ml at day 0. Subsequently, it decreased with time. While rabbit-IgG was detectable for a long period (e.g. 160 microg/ml at day +22 in patient MD), the effect on the phytohaemagglutinin-response of normal mononuclear cells lasted up to 4 days post transplant. We conclude that 90 mg/kg body weight ATG-Fresenius given prior to marrow transplant leads to sustained T cell immunosuppression post transplant.
authors.affiliation: Department of Transfusion Medicine, University Hospital Eppendorf, Hamburg, Germany.
authors.forename: T H
authors.initials: TH
authors.lastname: Eiermann
authors.forename: P
authors.initials: P
authors.lastname: Lambrecht
authors.forename: A R
authors.initials: AR
authors.lastname: Zander
mesh_terms: D000328:Adult; D000818:Animals; D000961:Antilymphocyte Serum / Q000097:blood*; D016026:Bone Marrow Transplantation / Q000009:adverse effects*; D004797:Enzyme-Linked Immunosorbent Assay; D006086:Graft vs Host Disease / Q000517:prevention & control*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007166:Immunosuppressive Agents / Q000097:blood*; D008213:Lymphocyte Activation; D008875:Middle Aged; D011817:Rabbits
chemical_list: D000961:Antilymphocyte Serum; D007074:Immunoglobulin G; D007166:Immunosuppressive Agents