title: In vitro effects of ATG-Fresenius on immune cell adhesion.
abstract: BACKGROUND
  ATG-Fresenius, a purified rabbit polyclonal anti-human T-lymphocyte immunoglobulin is used for induction immunosuppression as well as prevention and treatment of acute rejection episodes among patients receiving solid organ transplants. The aim of this study was to investigate the in vitro activity of ATG-Fresenius upon immune cell adhesion, which may explain its activity to mitigate ischemia-reperfusion injury.
  
  
  METHODS
  Human vascular endothelial cells (HUVEC) and peripheral blood mononuclear cells (PBMCs) isolated from umbilical vein or peripheral blood were incubated 20 to 24 hours before analysis. HUVEC were incubated with 10 and 100 μg/mL ATG-Fresenius or reference polyclonal rabbit immunoglobulin G. Analysis of immune cell adhesion to endothelial cells was studied in cocultures of PBMCs and adherent HUVEC. Endothelial cell expression of adhesion molecules CD62E and CD54 was determined by flow cytometry. The numbers of T-, B- and natural killer cells attached to HUVEC were also determined by flow cytometry. Groups were compared using one-way analysis of variance.
  
  
  RESULTS
  We showed that ATG-Fresenius binds to endothelial cells particularly activated ones expressing increased levels of E-selectin and ICAM-1. The increased binding of ATG-Fresenius to activated endothelial cells was consistent with its known binding to Intercellular Adhesion Molecule 1 (ICAM-1) and selectins. We also showed that ATG-Fresenius inhibited adhesion of prestimulated immune cells to activated endothelium.
  
  
  CONCLUSIONS
  We demonstrated dose-dependent binding of ATG-Fresenius to activated endothelial cells.
authors.affiliation: Department of Cardiothoracic and Vascular Surgery, J.W. Goethe University Hospital, Frankfurt, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Kanzler
authors.forename: I
authors.initials: I
authors.lastname: Seitz-Merwald
authors.forename: S
authors.initials: S
authors.lastname: Schleger
authors.forename: I
authors.initials: I
authors.lastname: Kaczmarek
authors.forename: F
authors.initials: F
authors.lastname: Kur
authors.forename: A
authors.initials: A
authors.lastname: Beiras-Fernandez
mesh_terms: D001402:B-Lymphocytes / Q000166:cytology*; D002448:Cell Adhesion; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology*; D005434:Flow Cytometry; D006801:Humans; D007136:Immunoglobulins / Q000008:administration & dosage*; D066298:In Vitro Techniques; D007694:Killer Cells, Natural / Q000166:cytology*; D013601:T-Lymphocytes / Q000166:cytology*
chemical_list: D007136:Immunoglobulins