CloneID: hu3B9
Antigen Long Description: The original antibody was generate by immunizing F1 hybrids of Balb/c and C57BL/6 with E. Coli-produced recombinant human IL-4.
Buffer Composition: PBS with 0.02% Proclin 300.
Available Custom Conjugation Options: AP, HRP, Fluorescein, APC, PE, Biotin Type A, Biotin Type B, Streptavidin, FluoroProbes 647H, Atto488, APC/Cy7, PE/Cy7
Uniprot Accession No.: P05112
Specificity Statement: This antibody is specific for human IL-4 and binds a non-contiguous epitope.
Application Notes (Clone): The binding affinity of the original format and Fab fragment of this antibody were evaluated by ELISA. The original format of this antibody (mouse IgG1) exhibited a <0.2 nM Kd (~0.18 nM). The Kd of its Fab fragment was <0.3 nM. This antibody successfully inhibited IL-4 binding to its receptor, as evaluated using 125 I-rhIL4 binding to the gibbon cell line, MLA. This antibody successfully inhibited lymphocyte proliferation — the original format of this antibody inhibited 3 H-thymidine incorporation by human peripheral blood T lymphocytes stimulated with 133 pM IL-4 and human tonsillar B lymphocytes stimulated by 167 pM IL-4. The IC50 for inhibition of T cell proliferation was 30 pM, and for B cell proliferation 103 pM. The corresponding values for the Fab fragment were 108 and 393 pM. This antibody successfully inhibited CD23 induction — the original format of this antibody inhibited CD23 expression on human tonsil B lymphocytes stimulated with 8.3 pM IL-4 with an IC50 value of 136 pM. This antibody successfully inhibited IgE secretion — the original format and the Fab fragment of this antibody inhibited IgE secretion in the presence of 1.7 nM IL-4, giving IC50 values of 1.9 and 5.0 nM, respectively. The experiment was repeated using a lower concentration of IL-4, 667 pM, which reduced the IC50 value to 0.65 nM for the original format of the antibody. The humanized version of this antibody effectively inhibited the binding of IL-4 receptor-Fc fusion protein to IL-4 in a dose-dependent manner — at lower concentrations (10-20 nM), it achieved 50% inhibition, while at higher concentrations (1 µM), it achieves greater than 90% inhibition. In a pharmacokinetics experiment performed on male Sprague Dawley rats, the humanized version of this antibody exhibited low inter-animal variability with a slow plasma clearance value of 0.5 mL/h/kg and an approximate 11 days half-life with a biphasic disappearance pattern (US5914110A).