title: CD4 monoclonal antibody VIT4 in human alloimmune response in vitro and in vivo.
abstract: In the present report the immunosuppressive effects of the murine anti-human CD4 monoclonal antibody (mAb) VIT4 on human alloimmune response in vitro were analyzed. Moreover, the antibody was tested for its activity to prolong allograft survival in seven patients with steroid-refractory allograft rejection. VIT4 inhibited the proliferative response to alloantigens in the mixed lymphocyte reaction (MLR) in a dose-dependent manner. At concentrations of 1 and 10 micrograms/ml VIT4 blocked MLR by 55 +/- 11% and 77 +/- 1%, respectively. Also alloantigen-specific proliferation of in vitro- generated memory T cells was dose-dependently reduced to 23 +/- 1% at a VIT4 concentration of 100 micrograms/ml. Furthermore, at the same dose level VIT4 blocked proliferation of antigen-specific short-term alloreactive CD4+ cell lines and significantly inhibited the in vitro generation of cytotoxic T lymphocytes (CTL). In a pilot study VIT4 (5 mg/d i.v.) was administered to 7 patients with steroid-refractory allograft rejection for 14 days. In 4 of 7 patients graft function transiently improved and graft survival in all patients was prolonged to a mean of 694 days (range 128-2163) from the beginning of the VIT4 treatment. In the light of our in vitro results and the preliminary clinical data, further clinical trials using higher antibody doses are greatly warranted to assess the efficacy of anti-CD4 mAb VIT4 in the treatment of allograft rejection.
authors.affiliation: Department of Internal Medicine, University Hospital, Innsbruck, Austria.
authors.forename: D
authors.initials: D
authors.lastname: Nachbaur
authors.forename: D
authors.initials: D
authors.lastname: Niederwieser
authors.forename: G
authors.initials: G
authors.lastname: Aichinger
authors.forename: W
authors.initials: W
authors.lastname: Aulitzky
authors.forename: H
authors.initials: H
authors.lastname: Tilg
authors.forename: B
authors.initials: B
authors.lastname: Eibl
authors.forename: P
authors.initials: P
authors.lastname: König
authors.forename: C
authors.initials: C
authors.lastname: Gattringer
authors.forename: O
authors.initials: O
authors.lastname: Majdic
authors.forename: H
authors.initials: H
authors.lastname: Stockinger
authors.forename: R
authors.initials: R
authors.lastname: Margreiter
authors.forename: G
authors.initials: G
authors.lastname: Oberhuber
authors.forename: A M
authors.initials: AM
authors.lastname: Födinger
authors.forename: H
authors.initials: H
authors.lastname: Schwaighofer
authors.forename: C
authors.initials: C
authors.lastname: Huber
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000493:pharmacokinetics; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D004306:Dose-Response Relationship, Immunologic; D006084:Graft Rejection / Q000517:prevention & control*; D006801:Humans; D007156:Immunologic Memory; D007165:Immunosuppression Therapy / Q000379:methods*; D016030:Kidney Transplantation / Q000276:immunology*; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D016035:Pancreas Transplantation / Q000276:immunology*; D010865:Pilot Projects; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal