title: Development and analytical validation of an enzyme-linked immunosorbent assay (ELISA) for the measurement of alpha(1)-proteinase inhibitor in serum and faeces from cats.
abstract: The objective of this study was to develop and analytically validate an ELISA for the measurement of alpha(1)-proteinase inhibitor (α(1)-PI) in serum and faeces from cats. Lower detection limit, linearity, accuracy, precision, reproducibility, and reference intervals were determined. The lower detection limits were 0.02 g/L for serum and 0.04 μg/g for faeces. The observed-to-expected (O/E) ratios for serial dilutions of serum and faecal samples ranged from 100.0 to 129.7% (mean±SD: 112.2±9.9%) and 103.5 to 141.6% (115.6±12.8%), respectively. The O/E ratios for samples spiked with seven known concentrations of α(1)-PI ranged from 82.3 to 107.8% (94.7±7.6%) for serum, and 78.5 to 148.7% (96.8±18.2%) for faeces. The coefficients of variation for intra-assay and inter-assay variability were <7.9% and <12.1% for serum, and 5.3%, 11.8%, 14.2%, and 7.7%, 10.2%, 20.4% for faeces, respectively. Reference intervals were 0.6-1.4 g/L for serum and upto 1.6 μg/g for faeces. We conclude that this ELISA is sufficiently linear, accurate, precise, and reproducible for clinical evaluation.
authors.affiliation: The Gastrointestinal Laboratory, Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843-4474, USA. kburke@cvm.tamu.edu
authors.forename: K F
authors.initials: KF
authors.lastname: Burke
authors.forename: C G
authors.initials: CG
authors.lastname: Ruaux
authors.forename: J S
authors.initials: JS
authors.lastname: Suchodolski
authors.forename: D A
authors.initials: DA
authors.lastname: Williams
authors.forename: J M
authors.initials: JM
authors.lastname: Steiner
mesh_terms: D000818:Animals; D002415:Cats / Q000097:blood* / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary*; D005243:Feces / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000515:alpha 1-Antitrypsin / Q000097:blood* / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D000515:alpha 1-Antitrypsin