In vivo surveillance and elimination of teratoma-forming human embryonic stem cells with monoclonal antibody 2448 targeting annexin A2.

Abstract

This study describes the use of a previously reported chimerised monoclonal antibody (mAb), ch2448, to kill human embryonic stem cells (hESCs) in vivo and prevent or delay the formation of teratomas. ch2448 was raised against hESCs and was previously shown to effectively kill ovarian and breast cancer cells in vitro and in vivo. The antigen target was subsequently found to be Annexin A2, an oncofetal antigen expressed on both embryonic cells and cancer cells. Against cancer cells, ch2448 binds and kills via antibody-dependent cell-mediated cytotoxicity (ADCC) and/or antibody-drug conjugate (ADC) routes. Here, we investigate if the use of ch2448 can be extended to hESC. ch2448 was found to bind specifically to undifferentiated hESC but not differentiated progenitors. Similar to previous study using cancer cells, ch2448 kills hESC in vivo either indirectly by eliciting ADCC or directly as an ADC. The treatment with ch2448 post-transplantation eliminated the in vivo circulating undifferentiated cells and prevented or delayed the formation of teratomas. This surveillance role of ch2448 adds an additional layer of safeguard to enhance the safety and efficacious use of pluripotent stem cell-derived products in regenerative medicine. Thereby, translating the use of ch2448 in the treatment of cancers to a proof of concept study in hESC (or pluripotent stem cell [PSC]), we show that mAbs can also be used to eliminate teratoma forming cells in vivo during PSC-derived cell therapies. We propose to use this strategy to complement existing methods to eliminate teratoma-forming cells in vitro. Residual undifferentiated cells may escape in vitro removal methods and be introduced into patients together with the differentiated cells.

• Authors: Heng Liang Tan, Bao Zhu Tan, Winfred Xi Tai Goh, Simeon Cua, Andre Choo
• Journal: Biotechnology and bioengineering (Biotechnol Bioeng) Vol. 116 Issue 11 Pg. 2996-3005 (11 2019) ISSN: 1097-0290 [Electronic] United States
• PMID: 31388993 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2019 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.

Chemical References

• ANXA2 protein, human
• Annexin A2
• Antineoplastic Agents, Immunological
• Neoplasm Proteins

Topics

• Animals
• Annexin A2 (metabolism)
• Antineoplastic Agents, Immunological (pharmacology)
• Cell Tracking
• Heterografts
• Human Embryonic Stem Cells (metabolism, pathology)
• Humans
• Mice
• Mice, Inbred NOD
• Mice, SCID
• Neoplasm Proteins (metabolism)
• Stem Cell Transplantation
• Teratoma (diagnostic imaging, metabolism, pathology)