Next Article in Journal
Iron as Therapeutic Target in Human Diseases
Next Article in Special Issue
Current Status of PSMA-Radiotracers for Prostate Cancer: Data Analysis of Prospective Trials Listed on ClinicalTrials.gov
Previous Article in Journal
In Vitro Characterization and Stability Profiles of Antibody–Fluorophore Conjugates Derived from Interchain Cysteine Cross-Linking or Lysine Bioconjugation
Previous Article in Special Issue
Thermosensitive Nanosystems Associated with Hyperthermia for Cancer Treatment
Open AccessArticle

A Robust Method for Assaying the Immunoreactive Fraction in Nonequilibrium Systems

1
Department of Nuclear Medicine and Molecular Imaging, Lausanne University Hospital and University of Lausanne, Rue du Bugnon 46, 1011 Lausanne, Switzerland
2
Division of Immunology and Allergy, Department of Medicine, Lausanne University Hospital and University of Lausanne, Rue du Bugnon 46, 1011 Lausanne, Switzerland
*
Author to whom correspondence should be addressed.
Pharmaceuticals 2019, 12(4), 177; https://doi.org/10.3390/ph12040177
Received: 25 October 2019 / Revised: 29 November 2019 / Accepted: 29 November 2019 / Published: 3 December 2019
The immunoreactive fraction r provides important information on the functional purity of radiolabeled proteins. It is traditionally determined by saturating the radioimmunoconjugate with an increasing excess of antigen, followed by linear extrapolation to infinite antigen excess in a double inverse “Lindmo plot”. Although several reports have described shortcomings in the Lindmo plot, a systematic examination is lacking. Using an experimental and simulation-based approach, we compared—for accuracy, precision and robustness—the Lindmo plot with the “rectangular hyperbola” extrapolation method based on the Langmuir model. The differences between the theoretical and extrapolated r values demonstrate that nonequilibrium and antigen depletion are important sources of error. The mathematical distortions resulting from the linearization of the data in the Lindmo plot induce fragility towards stochastic errors and make it necessary to exclude low bound fractions. The rectangular hyperbola provides robust and precise r estimates from raw binding data, even for slow kinetics. View Full-Text
Keywords: translational pharmacology; immunoreactivity; radiopharmaceuticals; radiolabeled antibodies; binding sites; antibody; immunoconjugates; Lindmo plot translational pharmacology; immunoreactivity; radiopharmaceuticals; radiolabeled antibodies; binding sites; antibody; immunoconjugates; Lindmo plot
Show Figures

Graphical abstract

MDPI and ACS Style

Denoël, T.; Pedrelli, L.; Pantaleo, G.; Prior, J.O. A Robust Method for Assaying the Immunoreactive Fraction in Nonequilibrium Systems. Pharmaceuticals 2019, 12, 177.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop