DNA-Mediated Assembly of Multispecific Antibodies for T Cell Engaging and Tumor Killing

Area of Science:

• Immunology
• Biotechnology
• Molecular Engineering

Background:

• Targeting T-cells to cancer cells is an effective cancer treatment strategy, particularly for B-cell malignancies.
• Multispecific antibodies (MsAbs) can redirect T-cells to cancer cells for targeted tumor killing.
• Existing methods for MsAb construction can be complex.

Purpose of the Study:

• To develop a novel multispecific antibody (MsAb) using a nucleic acid mediated protein-protein assembly (NAPPA) approach.
• To create a MsAb capable of directing T-cells to engage and kill tumor cells.
• To evaluate the efficacy of the NAPPA-assembled MsAb in vitro and in vivo.

Main Methods:

• Utilized a nucleic acid mediated protein-protein assembly (NAPPA) approach.
• Conjugated anti-CD19 and anti-CD3 single-chain variable fragments (scFvs) to distinct DNA strands designed to form a Holliday junction.
• Assembled homogeneous protein-DNA oligomers with a 2:1 ratio of anti-CD19 to anti-CD3 scFvs.

Main Results:

• The novel MsAb demonstrated potent induction of Raji tumor cell cytotoxicity in the presence of T-cells, with an EC50 of approximately 0.2 x 10^-9 M.
• The MsAb effectively suppressed tumor growth in a Raji xenograft mouse model.
• The protein-DNA conjugate assembly resulted in effective T-cell redirection for tumor killing.

Conclusions:

• MsAbs assembled via protein-DNA conjugates are effective macromolecules for directing T-cells against tumors.
• The NAPPA platform enables rapid generation of complex MsAbs from simple antibody fragments.
• This approach offers a versatile solution for preparing antibodies with high-order specificity for cancer therapy.