title: Relationship between erythrocyte-to-plasma distribution ratio of cyclosporin and lymphocyte proliferation in renal transplant patients.
abstract: OBJECTIVE
  The aim of this study was to examine the relationship between erythrocyte-to-plasma distribution ratio of cyclosporin (CsA-EP) and lymphocyte proliferation as an indicator of immunosuppressive activity in renal transplant patients.
  
  
  METHODS
  A total of 113 whole blood samples obtained from 6 inpatients with renal transplantation were analysed. CsA concentrations in blood and plasma at trough were measured by fluorescence polarization immunoassay using monoclonal antibody, lymphocyte proliferation in response to phytohaemagglutinin was evaluated by the fluorimetric derivatization method using ethidium bromide and the stimulation index (SI) was calculated.
  
  
  RESULTS
  There was no correlation between CsA dose and trough levels (vs blood CsA, r2 = 0.052; vs plasma CsA, r2 = 0.054, n = 113). A significant negative correlation between the SI and the CsA-EP was found in individual or all samples (r2 = 0.224, p < 0.0001, n = 113), whereas CsA trough levels in blood or plasma had no correlation with the SI.
  
  
  CONCLUSIONS
  Although the degree of contribution of CsA-EP to the SI was 22%, the CsA-EP is a more useful predictor of changes in immunosuppressive response than CsA concentration in blood or plasma. The adoption of the CsA-EP as a monitoring index could be helpful in assessing the appropriateness of CsA immunosuppressive therapy.
authors.affiliation: Department of Hospital Pharmacy, Shiga University of Medical Science, Otsu, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Shibata
authors.forename: N
authors.initials: N
authors.lastname: Hoshino
authors.forename: T
authors.initials: T
authors.lastname: Minouchi
authors.forename: A
authors.initials: A
authors.lastname: Yamaji
mesh_terms: D000328:Adult; D000410:Alanine Transaminase / Q000097:blood; D003401:Creatine / Q000097:blood; D003524:Cyclosporins / Q000097:blood* / Q000627:therapeutic use; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D016231:Fluorescence Polarization Immunoassay; D006801:Humans; D007166:Immunosuppressive Agents / Q000097:blood* / Q000627:therapeutic use; D016030:Kidney Transplantation / Q000276:immunology*; D008074:Lipoproteins / Q000097:blood; D008213:Lymphocyte Activation / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D008934:Mitogens / Q000494:pharmacology
chemical_list: D003524:Cyclosporins; D007166:Immunosuppressive Agents; D008074:Lipoproteins; D008934:Mitogens; D000410:Alanine Transaminase; D003401:Creatine