Bispecific Antibodies for IFN-β Delivery to ErbB2+ Tumors

Abstract

The main aim of our work was to create a full-length bispecific antibody (BsAb) as a vehicle for the targeted delivery of interferon-beta (IFN-β) to ErbB2+ tumor cells in the form of non-covalent complex of BsAb and IFN-β. Such a construct is a CrossMab-type BsAb, consisting of an ErbB2-recognizing trastuzumab moiety, a part of chimeric antibody to IFN-β, and human IgG1 Fc domain carrying knob-into-hole amino acid substitutions necessary for the proper assembly of bispecific molecules. The IFN-β- recognizing arm of BsAb not only forms a complex with the cytokine but neutralizes its activity, thus providing a mechanism to avoid the side effects of the systemic action of IFN-β by blocking IFN-β Interaction with cell receptors in the process of cytokine delivery to tumor sites. Enzyme sandwich immunoassay confirmed the ability of BsAb to bind to human IFN-β comparable to that of the parental chimeric mAb. The BsAb binds to the recombinant ErbB2 receptor, as well as to lysates of ErbB2+ tumor cell lines. The inhibition of the antiproliferative effect of IFN-β by BsAb (IC50 = 49,3 µg/mL) was demonstrated on the HT29 cell line. It can be proposed that the BsAb obtained can serve as a component of the immunocytokine complex for the delivery of IFN-β to ErbB2-associated tumor cells.

Targeted Cytokine Delivery for Cancer Treatment: Engineering and Biological Effects

“…However, to overcome these distinct adverse effects, scientists have designed masked immunocytokines, activated by matrix metalloproteases or tumor-specific proteases [ 42 , 43 , 140 ]. Another strategy focuses on cytokine moiety engineering, with a purpose to decrease the affinity of the cytokines to high-affinity receptors expressed on normal cells [ 44 , 141 ]. A prolonged half-life of immunocytokines may be another reason for their limited achievable dosing compared to free cytokines.…”

“…This concept was applied in the construction of the molecular complex of IFN-β and anti-ErbB2 IFN-β-neutralizing bispecific antibody (Tz-B16) for ErbB2+ solid tumor treatment ( Figure 1 ). One arm of the bispecific antibody is responsible for the ErbB2 targeting of the complex, while the second arm forms the antibody–interferon neutralizing complex, which dissociates at the tumor site [ 44 ]. Summing up, each of the formats has its own advantages and limitations, making the choice of the optimal structure of the immunocytokine molecule ambiguous and controversial.…”

“…One of the strategies is to deliver interferon by a bispecific antibody targeted to the tumor cell marker and capable of binding and neutralizing the interferon with a second arm, thus disrupting interferon–receptor interactions during transportation, which may cause potential side effects. Due to high molecular weight, the molecular structure comparable to IgG and the active Fc-part of this complex is stable and might sustain satisfactory serum persistence [ 44 , 120 ]. Another strategy uses latency-associated protein of TGF-β1 fused to IFN-β via a matrix metalloproteinase labile linker, which is responsible for masking interferon from receptor interactions.…”

Strategies and Considerations for Improving Recombinant Antibody Production and Quality in Chinese Hamster Ovary Cells

“…In recent years, recombinant antibody drugs are emerging with the rapid development of modern molecular biology technology as well as in-depth exploration on the three-dimensional structure and mechanism of action of antibody molecules. Recombinant antibody drugs undergo the stages of mouse monoclonal antibody, human-mouse chimeric antibody, humanized antibody, and fully human antibody ( Figure 1 ), which have been applied in many fields, such as anti-tumor, anti-autoimmune diseases, and biosensor ( DeLuca et al, 2021 ; Galvani et al, 2021 ; Liao et al, 2021 ; Rudenko et al, 2021 ; Rybchenko et al, 2021 ; Yang G et al, 2021 ). Improving the affinity of antibodies and reducing their immunogenicity are two basic principles of genetic engineering of antibody drugs.…”

Editorial for the Special Issue: “State-of-Art in Protein Engineering”

“…Rybchenko V. et al [ 3 ] described a new protein engineering approach for IFN-β delivery to ErbB2+ tumors. They developed a crossMab bispecific antibody with the ability to simultaneously bind two proteins, IFN-β and ErbB2+, to create a targeted molecular complex of cytokine and bispecific antibodies.…”