Blocking Monoclonal Antibodies Specific for Mouse IFN-α/β Receptor Subunit 1 (IFNAR-1) from Mice Immunized by In Vivo Hydrodynamic Transfection

KCF Sheehan, KS Lai, GP Dunn, AT Bruce… - Journal of interferon & …, 2006 - liebertpub.com
KCF Sheehan, KS Lai, GP Dunn, AT Bruce, MS Diamond, JD Heutel, C Dungo-Arthur…
Journal of interferon & cytokine research, 2006liebertpub.com
Herein we report the generation of mouse monoclonal antibodies (mAbs) specific for the
IFNAR-1 subunit of the mouse interferon-α/β (IFN-α/β) receptor (MAR1 mAbs) that block type
I IFN receptor signaling and biologic response induction in vitro and in vivo. These mAbs
were generated from Ifnar1–/–mice immunized by in vivo hydrodynamic transfection with a
plasmid encoding the extracellular domain (ECD) of murine IFNAR-1. All MAR1 mAbs
bound native receptor expressed on cell surfaces and immunoprecipitated IFNAR-1 from …
Herein we report the generation of mouse monoclonal antibodies (mAbs) specific for the IFNAR-1 subunit of the mouse interferon-α/β (IFN-α/β) receptor (MAR1 mAbs) that block type I IFN receptor signaling and biologic response induction in vitro and in vivo. These mAbs were generated from Ifnar1 –/– mice immunized by in vivo hydrodynamic transfection with a plasmid encoding the extracellular domain (ECD) of murine IFNAR-1. All MAR1 mAbs bound native receptor expressed on cell surfaces and immunoprecipitated IFNAR-1 from solubilized cells, and two mAbs also detected IFNAR-1 by Western blot analysis. in vitro, the mAbs prevented ligand-induced intracellular signaling and induction of a variety of type I IFN-induced biologic responses but had no effect on IFN-γ-induced responses. The most effective in vitro blocker, MAR1-5A3, also blocked type I IFN-induced antiviral, antimicrobial, and antitumor responses in vivo. We also explored whether murine IFNAR-1 surface expression required the presence of Tyk2. In contrast to Tyk2-deficient human cell lines, comparable IFNAR-1 expression was found on primary cells derived either from wild-type or Tyk2 –/– mice. These mAbs represent much needed tools to more clearly elucidate the biochemistry, cell biology, and physiologic function of the type I IFNs and their receptor in mediating host-protective immunity and immunopathology.
Mary Ann Liebert