Aim: To perform a site-specific conjugation of Fab' fragments of a mouse monoclonal antibody(MoAb) B43(of IgG1 subtype) to a bifunctional chelator 6-[p-(bromoacetamido)benzyl]-1,4,8,11-tetraazacyclotetradecane-N,N',N' 'N' ' '-tetraacetic acid (BAT) via the thiol groups in the hinge distal to the antigen-binding site of the Fab'.
Methods: B43 was cleaved using a simple 2-step method. First, stable F(ab')(2) was produced by pepsin treatment. Fab' with free thiol in the hinge region was then obtained by cysteine reduction of F(ab')2. Second, a site-specific conjugation of Fab' to thiol-specific BAT was performed in a one-step reaction.
Results: The Fab' fragment had approximately 1.8 free thiol groups per molecule after cysteine reduction. The conjugation efficiency and the chemical yield were approximately 1.28 moles chelator/Fab' and 74% of the initial concentration of Fab', respectively. The F(ab')2, Fab' and Fab'-BAT all maintained reasonable antigen-binding properties. (67)Cu labeling of the conjugate under standard conditions did not impair the immunoreactivity of Fab'-BAT.
Conclusion: This is a simple and efficient method for producing immunoreactive conjugates of Fab'-BAT, which can be used to make radiometal-labeled conjugates for further diagnostic and therapeutic applications.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1111/j.1745-7254.2006.00242.x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
The current research discusses polymer conjugation, formulation development, and evaluation of sorafenib-loaded polymeric nanomicelles of conjugated soluplus (solu-tin) and polymeric mixed nanomicelles of conjugated soluplus (solu-tin) with conjugated poloxamer 188 (polo-tin) for site-specific posterior segment delivery to the retina in managing retinoblastoma. Firstly, the soluplus and poloxamer 188 were conjugated with biotin by Fischer esterification reaction and evaluated by FTIR and H NMR for confirmation of covalent bond formation involving the carboxyl group of biotin and hydroxyl group of polymers. Secondly, the sorafenib-loaded solu-tin nanomicelles and mixed nanomicelles of solu-tin with polo-tin were formulated by the thin film hydration method.
View Article and Find Full Text PDFTargeting uPAR with an antibody-drug conjugate suppresses tumor growth and reshapes the immune landscape in pancreatic cancer models.
Sci Adv
January 2025
The Finsen Laboratory, Rigshospitalet, DK-2200 Copenhagen, Denmark.
Antibody-drug conjugates (ADCs) hold promise to advance targeted therapy of pancreatic ductal adenocarcinoma (PDAC), where the desmoplastic tumor stroma challenges effective treatment. Here, we explored the urokinase plasminogen activator receptor (uPAR) as a candidate ADC target in PDAC, harnessing its massive tumoral and stromal expression in this stroma-dense tumor. We generated a site-specific ADC offering high-affinity, cross-species reactivity, and efficient internalization of the anti-uPAR monoclonal antibody, FL1, carrying a potent anthracycline derivative (PNU-158692).
View Article and Find Full Text PDFEngineering Covalent Aptamer Chimeras for Enhanced Autophagic Degradation of Membrane Proteins.
Angew Chem Int Ed Engl
January 2025
Nanjing University, State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, CHINA.
Targeted degradation of membrane proteins represents an attractive strategy for eliminating pathogenesis-related proteins. Aptamer-based chimeras hold great promise as membrane protein degraders, however, their degradation efficacy is often hindered by the limited structural stability and the risk of off-target effects due to the non-covalent interaction with target proteins. We here report the first design of a covalent aptamer-based autophagosome-tethering chimera (CApTEC) for the enhanced autophagic degradation of cell-surface proteins, including transferrin receptor 1 (TfR1) and nucleolin (NCL).
View Article and Find Full Text PDFSite-Specific Molecular Engineering of Nanobody-Glucoside Conjugates for Enhanced Brain Tumor Targeting.
Bioconjug Chem
January 2025
Guangdong Provincial Key Laboratory of Advanced Biomaterials, Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
Nanobodies play an increasingly prominent role in cancer imaging and therapy. However, their efficacy is often constrained by inadequate tumor penetration and rapid clearance from the bloodstream, particularly in brain tumors due to the intractable blood-brain barrier (BBB). Glycosylation is a favorable strategy for modulating the biological functions of nanobodies, including permeability and pharmacokinetics, but it also leads to heterogeneous glycan structures, which affect the targeting ability, stability, and quality of nanobodies.
View Article and Find Full Text PDFDeciphering Polymer Interactions in Bioconjugates with Different Architectures by Structural Analysis via Time-Resolved Limited Proteolysis Mass Spectrometry.
Angew Chem Int Ed Engl
January 2025
Universität Würzburg, Institute for Pharmacy and Food Chemistry, Am Hubland, 97074, Würzburg, Germany.
Therapeutic proteins are commonly conjugated with polymers to modulate their pharmacokinetics but often lack a description of the polymer-protein interaction. We deployed limited proteolysis mass spectrometry (LiP-MS) to reveal the interaction of polyethylene glycol (PEG) and PEG alternative polymers with interferon-α2a (IFN). Target conjugates were digested with the specific protease trypsin and a "heavy" N-IFN wild type (IFN-WT) for time-resolved quantification of the cleavage dynamics.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!