Humanizing murine IgG3 anti-GD2 antibody m3F8 substantially improves antibody-dependent cell-mediated cytotoxicity while retaining targeting in vivo Academic Article Article uri icon

Overview

MeSH Major

  • Immunity, Innate
  • Interleukin-17
  • Lymphocytes
  • Multipotent Stem Cells

abstract

  • Murine IgG3 anti-GD2 antibody m3F8 has shown anti-neuroblastoma activity in Phase I/II studies, where antibody-dependent cell-mediated cytotoxicity (ADCC) played a key role. Humanization of m3F8 should circumvent human anti-mouse antibody (HAMA) response and enhance its ADCC properties to reduce dosing and pain side effect. Chimeric 3F8 (ch3F8) and humanized 3F8 (hu3F8-IgG1 and hu3F8-IgG4) were produced and purified by protein A affinity chromatography. In vitro comparison was made with m3F8 and other anti-GD2 antibodies in binding, cytotoxicity, and cross-reactivity assays. In GD2 binding studies by SPR, ch3F8 and hu3F8 maintained K(D) comparable to m3F8. Unlike other anti-GD2 antibodies, m3F8, ch3F8 and hu3F8 had substantially slower k(off.). Similar to m3F8, both ch3F8 and hu3F8 inhibited tumor cell growth in vitro, while cross-reactivity with other gangliosides was comparable to that of m3F8. Both peripheral blood mononuclear cell (PBMC)-ADCC and polymorphonuclear leukocytes (PMN)-ADCC of ch3F8 and hu3F8-IgG1 were more potent than m3F8. This superiority was consistently observed in ADCC assays, irrespective of donors or NK-92MI-transfected human CD16 or CD32, whereas complement mediated cytotoxicity (CMC) was reduced. As expected, hu3F8-IgG4 had near absent PBMC-ADCC and CMC. Hu3F8 and m3F8 had similar tumor-to-non tumor ratios in biodistribution studies. Anti-tumor effect against neuroblastoma xenografts was better with hu3F8-IgG1 than m3F8. In conclusion, humanizing m3F8 produced next generation anti-GD2 antibodies with substantially more potent ADCC in vitro and anti-tumor activity in vivo. By leveraging ADCC over CMC, they may be clinically more effective, while minimizing pain and HAMA side effects. A Phase I trial using hu3F8-IgG1 is ongoing.

publication date

  • November 2, 2012

Research

keywords

  • Academic Article

Identity

Digital Object Identifier (DOI)

  • 10.4161/onci.19864

PubMed ID

  • 22754766

Additional Document Info

start page

  • 477

end page

  • 486

volume

  • 1

number

  • 4