Humans ; Antibodies, Bispecific/therapeutic use* ; Hematologic Neoplasms/therapy* ; Immunotherapy ; Neoplasms

Bispecific antibody (BsAb) has two different antigen-binding sites, divided into the "IgG-like" format and the "non-IgG-like" format. Different formats have different characteristics and applications. BsAb has higher sensitivity and specificity than conventional antibodies, with special functions such as recruitment of immune cells and blocking of dual signaling pathways, playing an important role in immune-diagnosis and therapy. With the deterioration of the global environment and the irregular living habits of people, the incidence of tumor is becoming higher and higher. Tumor becomes the most serious fatal disease threatening human health after cardiovascular disease. There are 12 million estimated new tumor cases each year worldwide. The major clinical treatments of tumor are surgical resection, chemoradiotherapy, target therapy. Tumor immunotherapy is a novel approach for tumor treatment in recent years, and activates human immune system to control and kill tumor cells. Although the traditional monoclonal antibodies have already acquired some therapeutic effects in tumor targeted therapy and immunotherapy, they induce drug resistance resulted from the heterogeneity and plasticity of tumors. Binding to two target antigens at the same time, BsAb has been used in the clinical treatment of tumors and obtained promising outcomes. This review elaborates the research progress and applications of bispecific antibody in clinical tumor therapy.
Antibodies, Bispecific/therapeutic use* ; Antibodies, Monoclonal/therapeutic use* ; Humans ; Immunotherapy ; Neoplasms/therapy*

With the rapid development of antibody genetic engineering, bispecific antibody technology has been advanced. They are capable of binding two or more different epitopes simultaneously, thus offering specific advantages over natural monoclonal antibodies in immunotherapy. Bispecific antibodies have been successfully used in cancer therapy (e.g. melanoma, Hodgkin's lymphoma, liver cancer, and stomach cancer) and inflammation therapy (e.g. rheumatoid arthritis, psoriasis and Crohn's disease), but are still in their early stage for viral immunotherapy. In this study, we reviewed the research progress of bispecific antibodies for immunotherapy of virus infections, especially those with good effects in vivo and in vitro, to provide references for the research and development of bispecific antibodies for antivirus treatment.
Antibodies, Bispecific ; therapeutic use ; Antibodies, Monoclonal ; Epitopes ; Humans ; Immunotherapy ; Virus Diseases

Immunotherapy plays a compelling role in cancer treatment and has already made remarkable progress. However, many patients receiving immune checkpoint inhibitors fail to achieve clinical benefits, and the response rates vary among tumor types. New approaches that promote anti-tumor immunity have recently been developed, such as small molecules, bispecific antibodies, chimeric antigen receptor T cell products, and cancer vaccines. Small molecule drugs include agonists and inhibitors that can reach the intracellular or extracellular targets of immune cells participating in innate or adaptive immune pathways. Bispecific antibodies, which bind two different antigens or one antigen with two different epitopes, are of great interest. Chimeric antigen receptor T cell products and cancer vaccines have also been investigated. This review explores the recent progress and challenges of different forms of immunotherapy agents and provides an insight into future immunotherapeutic strategies.
Antibodies, Bispecific/therapeutic use* ; Cancer Vaccines ; Humans ; Immunotherapy ; Neoplasms/therapy* ; Receptors, Chimeric Antigen ; T-Lymphocytes

We present a bispecific antibody that recognizes an antigen and a hapten and can be applied to various biological assays, including immunoblotting and immunoprecipitation. In immunoblot analysis of serum, an anti-C5 x anti-cotinine bispecific tandem single-chain variable fragment (scFv)-Fc fusion protein and cotinine-conjugated horseradish peroxidase (HRP) generated a clean signal without the high background that was observed in a parallel experiment using HRP-conjugated goat anti-rabbit immunoglobulin G (Fc-specific) antibody. In immunoprecipitation analysis of serum, use of the bispecific tandem scFv-Fc fusion protein and cotinine-crosslinked magnetic beads significantly reduced the amount of protein contaminants compared with a parallel experiment done with protein A agarose beads. In subsequent immunoblot analysis, use of cotinine-HRP as the secondary probe instead of HRP-conjugated goat anti-rabbit IgG (Fc-specific) antibody successfully eliminated the band corresponding to the bispecific tandem scFv-Fc fusion protein.
Animals ; Antibodies, Bispecific/*immunology ; HEK293 Cells ; Haptens/*immunology ; Humans ; Immunoblotting/*methods ; Immunoprecipitation/methods ; Rabbits ; Single-Chain Antibodies/immunology

Tumor surface antigen human epidermal growth factor receptor 2 (Her2) is a type I receptor tyrosine kinase, which belongs to human epidermal growth factor receptor family. Her2-overexpression is associated with tumorigenesis and metastasis. Due to significant clinical effects, Her2-targeted cancer therapy especially therapeutic antibody has become the hot spot in the field of cancer treatment. Anti-Her2 antibody drugs include monoclonal antibodies, antibody-drug conjugates, bispecific antibodies and emerging "two in one" antibody. Based on structure and function of Her2, this review focuses on recent advances in active mechanisms and clinical researches of these antibodies.
Antibodies, Bispecific ; therapeutic use ; Antibodies, Monoclonal ; therapeutic use ; Humans ; Immunoconjugates ; therapeutic use ; Neoplasms ; drug therapy ; Receptor, ErbB-2 ; immunology

As of May 1, 2017, 74 antibody-based molecules have been approved by a regulatory authority in a major market. Additionally, there are 70 and 575 antibody-based molecules in phase III and phase I/II clinical trials, respectively. These total 719 antibody-based clinical stage molecules include 493 naked IgGs, 87 antibody-drug conjugates, 61 bispecific antibodies, 37 total Fc fusion proteins, 17 radioimmunoglobulins, 13 antibody fragments, and 11 immunocytokines. New uses for these antibodies are being discovered each year. For oncology, many of the exciting new approaches involve antibody modulation of T-cells. There are over 80 antibodies in clinical trials targeting T cell checkpoints, 26 T-cell-redirected bispecific antibodies, and 145 chimeric antigen receptor (CAR) cell-based candidates (all currently in phase I or II clinical trials), totaling more than 250 T cell interacting clinical stage antibody-based candidates. Finally, significant progress has been made recently on routes of delivery, including delivery of proteins across the blood-brain barrier, oral delivery to the gut, delivery to the cellular cytosol, and gene- and viral-based delivery of antibodies. Thus, there are currently at least 864 antibody-based clinical stage molecules or cells, with incredible diversity in how they are constructed and what activities they impart. These are followed by a next wave of novel molecules, approaches, and new methods and routes of delivery, demonstrating that the field of antibody-based biologics is very innovative and diverse in its approaches to fulfill their promise to treat unmet medical needs.
Animals ; Antibodies, Bispecific ; metabolism ; Antibodies, Monoclonal ; metabolism ; Drug Delivery Systems ; Humans ; Immunoconjugates ; metabolism ; Protein Engineering ; methods ; trends ; T-Lymphocytes ; metabolism

In order to enhance the specificity of TNF-α monoclonal antibody to inflamed site, a bispecific antibody BsDb that targets TNF-α and the extra-domain B (ED-B) of fibronectin (FN) was constructed by covalently linking the anti-TNF-α single chain Fv antibody (TNF-scFv) and the anti-ED-B scFv L19 via a flexible peptide linker deriving from human serum albumin (HSA). ED-B is an antigen specifically expressed at the inflamed site. BsDb is expressed in E. coli, identified by immunoblot, and purified with affinity chromatography. This was followed by further examination of its bioactivities and pharmacokinetics. We demonstrated that BsDb retained the immunoreactivity of its original antibodies as it could simultaneously bind to TNF-α and ED-B and neutralize the biological action of TNF-α. In the collagen-induced arthritis mice model, BsDb selectively accumulate in the inflamed joint with a maximal uptake of (12.2 ± 1.50)% ID/g in a single inflamed paw and retain in the inflamed paw for at least 72 h. In contrast, BsDb showed a short serum half-life of (0.50 ± 0.05) h and a rapid clearance from normal tissues. The findings reported herein indicate that BsDb has good specificity to the inflamed site and low toxicity to normal tissues. BsDb is therefore likely to have greater clinical applications in the treatment of rheumatoid arthritis and other autoimmune diseases. This laid a stable basis for its preclinical study.
Animals ; Antibodies, Bispecific ; chemistry ; Antibodies, Monoclonal ; chemistry ; Arthritis, Experimental ; Escherichia coli ; Fibronectins ; chemistry ; Half-Life ; Humans ; Mice ; Single-Chain Antibodies ; chemistry ; Tumor Necrosis Factor-alpha ; chemistry

To enhance the specificity of anti-TNF-α single chain Fv antibody (TNF-scFv) to inflamed site, we constructed a bispecific antibody BsDb that targets TNF-α and ED-B-containing fibronectin (B-FN) by covalently linking TNF-scFv and the anti-ED-B scFv L19 at the gene level via a flexible peptide linker deriving from human serum albumin. BsDb was successfully secreted from Pichia pastoris as functional protein, identified by immunoblotting, and purified to homogeneity with affinity chromatography. BsDb retained the immunoreactivity of its original antibodies TNF-scFv and L19, and showed a marked gain in antigen-binding affinity and in TNF-α-neutralizing ability, when compared to TNF-scFv and L19 that were produced in Escherichia coli. In the adjuvant-induced arthritis (AIA) mice model, BsDb showed selective accumulation and retention in the inflamed paws but rapid clearance from blood, resulting in high arthritic paw to blood ratios. These data indicate that BsDb is endowed with high specificity to inflamed site and low toxicity to normal tissues and holds great potential for in vivo application for the targeted therapy of RA and other chronic inflammatory diseases.
Animals ; Antibodies, Bispecific ; biosynthesis ; immunology ; Antibodies, Neutralizing ; biosynthesis ; immunology ; Escherichia coli ; Fibronectins ; chemistry ; immunology ; Humans ; Mice ; Single-Chain Antibodies ; biosynthesis ; immunology ; Tumor Necrosis Factor-alpha ; immunology

There is growing evidence that crosstalk between mantle cell lymphoma (MCL) cells and stromal microenvironments, such as bone marrow and secondary lymphoid tissues, promotes tumor progression by enhancing survival and growth as well as drug resistance of MCL cells. Recent advances in the understanding of lymphoma microenvironment have led to the identification of crucial factors involved in the crosstalk and subsequent generation of their targeted agents. In the present study, we evaluated the combinatory effect of blocking antibodies (Ab) targeting CXCR4 and VLA-4, both of which were known to play significant roles in the induction of environment-mediated drug resistance (EMDR) in MCL cell line, Jeko-1. Simultaneous treatment with anti-CXCR4 and anti-VLA-4 Ab not only reduced the migration of Jeko-1 cells into the protective stromal cells, but also enhanced sensitivity of Jeko-1 to a chemotherapeutic agent to a greater degree than with either Ab alone. These combinatorial effects were associated with decreased phosphorylation of ERK1/2, AKT and NF-kappaB. Importantly, drug resistance could not be overcome once the adhesion of Jeko-1 to the stromal occurred despite the combined use of Abs, suggesting that the efforts to mitigate migration of MCLs should be attempted as much as possible. Our results provide a basis for a future development of therapeutic strategies targeting both CXCR4 and VLA-4, such as Ab combinations or bispecific antibodies, to improve treatment outcomes of MCL with grave prognosis.
Antibodies, Bispecific ; Antibodies, Blocking ; Bone Marrow ; Cell Line ; Drug Resistance ; Drug Therapy* ; Integrin alpha4beta1* ; Lymphoid Tissue ; Lymphoma ; Lymphoma, Mantle-Cell* ; NF-kappa B ; Phosphorylation ; Prognosis ; Stromal Cells