title: Soluble CD-4 and CD-8 as markers of immunological activation in renal transplant recipients.
abstract: BACKGROUND
  T lymphocytes are activated following kidney transplantation in cases of acute graft rejection and viral infections. In plasma, elevated levels of T-cell markers can be measured in soluble form. The reason for this shedding is still not entirely understood.
  
  
  METHODS
  Plasma concentrations of soluble CD-4 and CD-8 (sCD-4, sCD-8) were determined in 78 patients following kidney transplantation by commercially available enzyme-linked immunosorbent assay (ELISA) test kits.
  
  
  RESULTS
  The concentrations of both soluble T-cell markers increased significantly in the course of acute allograft rejections and cytomegalovirus (CMV) infections. Frequently, the parameters increased shortly before clinical diagnosis and decreased under successful therapy. Additionally, sCD-8 showed significant higher plasma concentrations in cases of CMV infection as compared with acute allograft rejections. Accordingly, the sCD-4/sCD-8 ratio increased in cases of acute allograft rejection and decreased during CMV infections. Cyclosporin A nephrotoxicity caused no significant changes in the sCD-4 and sCD-8 levels in plasma.
  
  
  CONCLUSIONS
  The present study demonstrates that sCD-4 and sCD-8 are markers of immunological activation and may enable a further differentiation of T-cell activation if serial measurements are performed. However, further prospective investigations are necessary to elucidate the diagnostic potential of sCD-4 and sCD-8 for monitoring acute rejection and viral infection in kidney graft recipients.
authors.affiliation: Division of Nephrology and Rheumatology, Department of Internal Medicine, University of Göttingen, Germany.
authors.forename: R W
authors.initials: RW
authors.lastname: Grunewald
authors.forename: G M
authors.initials: GM
authors.lastname: Fiedler
authors.forename: B
authors.initials: B
authors.lastname: Stock
authors.forename: J M
authors.initials: JM
authors.lastname: Grunewald
authors.forename: G A
authors.initials: GA
authors.lastname: Müller
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D015704:CD4 Antigens / Q000097:blood*; D016827:CD8 Antigens / Q000097:blood*; D016022:Case-Control Studies; D003586:Cytomegalovirus Infections / Q000175:diagnosis / Q000209:etiology / Q000276:immunology; D003937:Diagnosis, Differential; D005260:Female; D006084:Graft Rejection / Q000175:diagnosis / Q000209:etiology / Q000276:immunology; D006801:Humans; D016030:Kidney Transplantation / Q000009:adverse effects / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D012995:Solubility
chemical_list: D015415:Biomarkers; D015704:CD4 Antigens; D016827:CD8 Antigens