Vaccinia Display of full-length human IgG

Billions of Antibodies – No transfections – No tolerance

ActivMAb® combines the throughput of phage and yeast display with mammalian-cell quality control in one platform to enable selection of full-length human IgG antibodies that have built-in manufacturability and favorable biophysical properties ideally suited for downstream development.

  • Full length IgG-Vaccinia membrane protein fusion allows for incorporation and display of the Ig-fusion protein on both the vaccinia virus membrane and on the mammalian cell surface
  • Similar in concept to phage display, except we are using full length IgG and mammalian expression
  • Vaccinia expressed antibodies must pass mammalian cell quality control before expression on the virus or the cell surface
  • Selection done in 2 different stages:
    • Panning
    • Cell Sorting


Panning: Antibody Display on the Virus

  • Rapid screening of billions of antibody combinations in a cell free selection system.
  • Virus can be concentrated from liters of cell culture supernatant to very small volume by high-speed centrifugation
  • >1X1010 antibody combinations can be screened in a single tube



Cell Sorting: Precision Selection

  • After several rounds of panning, the library complexity is reduced, and the percent of specific binders is correspondingly enriched. This allows the sorter to be used as a precision instrument.
    • Cell-surface expression with affinity selection by antigen titration and visualization of IgG selection
    • Selected antibodies fit into desired affinity window and will express well
    • Affinity can be readily improved by light chain optimization or mutagenesis