Development and validation of an enzyme-linked immunosorbent assay for feline trypsin-like immunoreactivity.
OBJECTIVE
To develop and validate an ELISA for quantitative analysis of feline trypsin-like immunore-activity (fTLI).


METHODS
Purified feline cationic trypsin (fCT) and rabbit anti-fCT antiserum; blood samples from 63 healthy cats.


METHODS
A sandwich capture ELISA was developed, using anti-fCT antiserum purified by affinity chromatography that underwent biotinylation. Purified fCT was used for standards. The assay was validated by determination of sensitivity, working range, linearity, accuracy, precision, and reproducibility. A reference range was established by assaying serum samples from the 63 healthy cats.


RESULTS
Sensitivity was 1.23 microg/L; working range was 2 to 567 microg/L. Ratios of observed versus expected results for 4 samples tested at various dilutions ranged from 90.0 to 120.7%. Ratios of observed versus expected results for 5 samples spiked with various concentrations of fCT ranged from 82.0 to 101.8%. Intra- and inter-assay coefficients of variability ranged from 9.9 to 11.1% and from 10.2 to 21.7%, respectively. The reference range for serum fTLI measured with this ELISA was 12 to 82 microg/L.


CONCLUSIONS
Results suggest that an ELISA can be used to measure serum fTLI in cats. The ELISA was sufficiently sensitive, linear, accurate, precise, and reproducible for clinical use.
Steiner
J M
JM
Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, Texas A&M University, College Station 77843-4474, USA.
Williams
D A
DA
Moeller
E M
EM
Melgarejo
T
T
D000818:Animals; D002371:Cat Diseases / Q000097:blood / Q000175:diagnosis; D002415:Cats / Q000097:blood / Q000502:physiology*; D002846:Chromatography, Affinity / Q000662:veterinary; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary*; D010179:Pancreas / Q000502:physiology*; D010182:Pancreatic Diseases / Q000097:blood / Q000175:diagnosis / Q000662:veterinary; D011817:Rabbits; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014107:Tosyllysine Chloromethyl Ketone / Q000737:chemistry; D014357:Trypsin / Q000097:blood*
D014107:Tosyllysine Chloromethyl Ketone; D014357:Trypsin