Antibody Therapeutics最新文献

Diseases in the central nervous system (CNS) are often difficult to treat. Antibody- and protein-based therapeutics hold huge promises in CNS disease treatment. However, proteins are restricted from entering the CNS by the blood-brain barrier (BBB). To achieve enhanced BBB crossing, antibody-based carriers have been developed by utilizing the endogenous macromolecule transportation pathway, known as receptor-mediated transcytosis. In this report, we first provided an overall review on key CNS diseases and the most promising antibody- or protein-based therapeutics approved or in clinical trials. We then reviewed the platforms that are being explored to increase the macromolecule brain entry to combat CNS diseases. Finally, we have analyzed the lessons learned from past experiences and have provided a perspective on the future engineering of novel delivery vehicles for antibody- and protein-based therapies for CNS diseases.

Background: Interleukin (IL)25 has been implicated in tissue homeostasis at barrier surfaces and the initiation of type two inflammatory signaling in response to infection and cell injury across multiple organs. We sought to discover and engineer a high affinity neutralizing antibody and evaluate the antibody functional activity in vitro and in vivo.

Methods: In this study, we generated a novel anti-IL25 antibody (22C7) and investigated the antibody's therapeutic potential for targeting IL25 in inflammation.

Results: A novel anti-IL25 antibody (22C7) was generated with equivalent in vitro affinity and potency against the human and mouse orthologs of the cytokine. This translated into in vivo potency in an IL25-induced air pouch model where 22C7 inhibited the recruitment of monocytes, macrophages, neutrophils and eosinophils. Furthermore, 22C7 significantly reduced ear swelling, acanthosis and disease severity in the Aldara mouse model of psoriasiform skin inflammation. Given the therapeutic potential of IL25 targeting in inflammatory conditions, 22C7 was further engineered to generate a highly developable, fully human antibody while maintaining the affinity and potency of the parental molecule.

Conclusions: The generation of 22C7, an anti-IL25 antibody with efficacy in a preclinical model of skin inflammation, raises the therapeutic potential for 22C7 use in the spectrum of IL25-mediated diseases.

Antibody therapies have become an important class of therapeutics in recent years as they have exhibited outstanding efficacy and safety in the treatment of several major diseases including cancers, immune-related diseases, infectious disease and hematological disease. There has been significant progress in the global research and development landscape of antibody therapies in the past decade. In this review, we have collected available data from the Umabs Antibody Therapies Database (Umabs-DB, https://umabs.com) as of 30 June 2022. The Umabs-DB shows that 162 antibody therapies have been approved by at least one regulatory agency in the world, including 122 approvals in the US, followed by 114 in Europe, 82 in Japan and 73 in China, whereas biosimilar, diagnostic and veterinary antibodies are not included in our statistics. Although the US and Europe have been at the leading position for decades, rapid advancement has been witnessed in Japan and China in the past decade. The approved antibody therapies include 115 canonical antibodies, 14 antibody-drug conjugates, 7 bispecific antibodies, 8 antibody fragments, 3 radiolabeled antibodies, 1 antibody-conjugate immunotoxin, 2 immunoconjugates and 12 Fc-Fusion proteins. They have been developed against 91 drug targets, of which PD-1 is the most popular, with 14 approved antibody-based blockades for cancer treatment in the world. This review outlined the global landscape of the approved antibody therapies with respect to the regulation agencies, therapeutic targets and indications, aiming to provide an insight into the trends of the global development of antibody therapies.

Amphiregulin is a transmembrane protein which, when cleaved by the TACE/ADAM17 protease, releases a soluble epidermal growth factor receptor ligand domain that promotes proliferation of normal and malignant cells. We previously described a rabbit monoclonal antibody, GMF-1A3, that selectively recognizes the cell-associated cleaved amphiregulin epitope. Antibody-drug conjugates had anti-tumor activity against human breast cancer xenografts. Several tumor types express amphiregulin, but evidence for a functional requirement for amphiregulin in these malignancies is limited. By directly evaluating amphiregulin cleavage with immunohistochemistry, GMF-1A3 provides a more direct measure of amphiregulin activity. Using 370 specimens from 10 tumor types (as well as normal controls), we demonstrate that cleaved amphiregulin is widely expressed in solid tumors and is especially common (> 50% of cases) in breast, prostate, liver and lung cancer. As a potential companion diagnostic for this antibody-drug conjugate, this assay allows identification of tumors with high levels of the cleaved amphiregulin target.

The classical `knob-into-holes' (KIH) strategy (knob(T366Y)/hole (Y407T)) has successfully enhanced the heterodimerization of a bispecific antibody (BsAb) resulting in heterodimer formation up to 92% of protein A (ProA)-purified protein pool. However, it does not show high efficiency for every BsAb. KIH was initially applied to a CD20/CD3 BsAb. After in silico modeling, two additional new mutations, S354Y in knob-heavy chain (HC) and Q347E in hole-HC, together with KIH named `ETYY', were introduced in the Fc. The CD20/CD3 BsAb hybrid only represented ~ 50% of the ProA-purified protein pool when KIH was applied. With ETYY, the percentage of CD20/CD3 hybrid increased to 93.8%. CD20/CD3-v4b (containing ETYY) retains the original activity of the BsAb at both Fab and Fc regions, and also shows good developability. These results indicate that the computer-aided novel ETYY design has the potential to improve the development of next-generation BsAbs with higher yields and simpler purification.

The diffusion interaction parameter (k_D ) has been demonstrated to be a high-throughput technique for characterizing interactions between proteins in solution. k_D reflects both attractive and repulsive interactions, including long-ranged electrostatic repulsions. Here, we plot the mutual diffusion coefficient (D_m ) as a function of the experimentally determined Debye-Hückel-Henry surface charge (Z_DHH ) for seven human monoclonal antibodies (mAbs) in 15 mM histidine at pH 6. We find that graphs of D_m versus Z_DHH intersect at Z_DHH, ~ 2.6, independent of protein concentration. The same data plotted as k_D versus Z_DHH show a transition from net attractive to net repulsive interactions in the same region of the Z_DHH intersection point. These data suggest that there is a minimum surface charge necessary on these mAbs needed to overcome attractive interactions.

Background: The use of Monoclonal Antibodies (MAbs) as therapeutics has been increasing over the past 30 years due to their high specificity and strong affinity toward the target. One of the major challenges toward their use as drugs is their low thermostability, which impacts both efficacy as well as manufacturing and delivery.

Methods: To aid the design of thermally more stable mutants, consensus sequence-based method has been widely used. These methods typically have a success rate of about 50% with maximum melting temperature increment ranging from 10 to 32°C. To improve the prediction performance, we have developed a new and fast MAbs specific method by adding a 3D structural layer to the consensus sequence method. This is done by analyzing the close-by residue pairs which are conserved in >800 MAbs' 3D structures.

Results: Combining consensus sequence and structural residue pair covariance methods, we developed an in-house application for predicting human MAb thermostability to guide protein engineers to design stable molecules. Major advantage of this structural level assessment is in significantly reducing the false positives by almost half from the consensus sequence method alone. This application has shown success in designing MAb engineering panels in multiple biologics programs.

Conclusions: Our data science-based method shows impacts in Mab engineering.

Background: CC chemokine receptor 7 (CCR7) is a member of G-protein-coupled receptor family and mediates chemotactic migration of immune cells and different cancer cells induced via chemokine (C-C motif) ligand 19 (CCL19) or chemokine (C-C motif) ligand 21 (CCL21). Hence, the identification of blockade antibodies against CCR7 could lead to the development of therapeutics targeting metastatic cancer.

Methods: CCR7 was purified and stabilized in its active conformation, and antibodies specific to purified CCR7 were screened from the synthetic M13 phage library displaying humanized scFvs. The in vitro characterization of selected scFvs identified two scFvs that exhibited CCL19-competitive binding to CCR7. IgG₄'s harboring selected scFv sequences were characterized for binding activity in CCR7⁺ cells, inhibitory activity toward CCR7-dependent cAMP attenuation, and the CCL19 or CCL21-dependent migration of CCR7⁺ cells.

Results: Antibodies specifically binding to purified CCR7 and CCR7⁺ cells were isolated and characterized. Two antibodies, IgG₄(6RG11) and IgG₄(72C7), showed ligand-dependent competitive binding to CCR7 with K_D values of 40 nM and 50 nM, respectively. Particularly, IgG₄(6RG11) showed antagonistic activity against CCR7, whereas both antibodies significantly blocked the ligand-induced migration and invasion activity of CCR7⁺ cancer cells.

Conclusions: Two antibody clones were successfully identified from a synthetic scFv-displaying phage library using purified recombinant CCR7 as an antigen. Antibodies specifically bound to the surface of CCR7⁺ cells and blocked CCR7⁺ cell migration. Particularly, 6RG11 showed antagonist activity against CCR7-dependent cAMP attenuation.

Additional COVID-19 vaccines that are safe and immunogenic are needed for global vaccine equity. Here, we developed a recombinant type 5 adenovirus vector encoding for the SARS-CoV-2 S1 subunit antigen and nucleocapsid as a fusion protein (Ad5.SARS-CoV-2-S1N). A single subcutaneous immunization with Ad5.SARS-CoV-2-S1N induced a similar humoral response, along with a significantly higher S1-specific cellular response, as a recombinant type 5 adenovirus vector encoding for S1 alone (Ad5.SARS-CoV-2-S1). Immunogenicity was improved by homologous prime-boost vaccination, and further improved through intramuscular heterologous prime-boost vaccination using subunit recombinant S1 protein. Priming with low dose (1 × 10¹⁰ v.p.) of Ad5.SARS-CoV-2-S1N and boosting with either wild-type recombinant rS1 or B.1.351 recombinant rS1 induced a robust neutralizing response, which was sustained against Beta and Gamma SARS-CoV-2 variants. This novel Ad5-vectored SARS-CoV-2 vaccine candidate showed promising immunogenicity in mice and supports the further development of COVID-19-based vaccines incorporating the nucleoprotein as a target antigen.