Monoclonal antibody fluorescent polarisation immunoassay versus 125Iode labelled ligand radioimmunoassay for the measurement of cyclosporine concentrations in whole blood.
Monoclonal antibody fluorescent polarisation immunoassay for cyclosporine in whole blood was first evaluated. Inter- and intra-assay CVs were less than 7%. We also compared concentrations measured by 125I-RIA and FPIA in specimens obtained from kidney and bone marrow transplanted patients. FPIA correlated well with 125I-RIA (slope = 1.03, r = 0.989, n = 58) over a wide range of concentrations (44-984 ng/ml). However, an additive bias estimated by the mean difference in cyclosporine concentrations between the 2 readings (44.1 +/- 44.3 ng/ml), led to overestimation of cyclosporine concentrations measured by FPIA. The monoclonal FPIA kit is therefore a rapid and reproductive method to monitor cyclosporine concentrations in whole blood. However, FPIA and 125I-RIA are not interchangeable and the therapeutic range of cyclosporine measured by FPIA should be defined.
Montes
C
C
Clinical Pharmacology Department, Hospital Robert-Debré, Paris, France.
Burtin
P
P
Jacqz-Aigrain
E
E
D000911:Antibodies, Monoclonal; D016026:Bone Marrow Transplantation; D016572:Cyclosporine / Q000097:blood*; D005454:Fluorescence Polarization; D006801:Humans; D007457:Iodine Radioisotopes; D016030:Kidney Transplantation; D011863:Radioimmunoassay; D012044:Regression Analysis
D000911:Antibodies, Monoclonal; D007457:Iodine Radioisotopes; D016572:Cyclosporine