Development Of Antibody Drugs Research Articles

1H, 13C and 15N resonance assignments of a shark variable new antigen receptor against hyaluronan synthase.

Single domain antibody (sdAb) is only composed of a variable domain of the heavy-chain-only antibody, which is devoid of light chain and naturally occurring in camelids and cartilaginous fishes. Variable New Antigen Receptor (VNAR), a type of single domain antibody present in cartilaginous fishes such as sharks, is the smallest functional antigen-binding fragment found in nature. The unique features, including flexible paratope, high solubility and outstanding stability make VNAR a promising prospect in antibody drug development and structural biology research. However, VNAR's research has lagged behind camelid-derived sdAb, especially in the field of structural research. Here we report the 1H,15N,13C resonance assignments of a VNAR derived from the immune library of Chiloscyllium plagiosum, termed B2-3, which recognizes the hyaluronan synthase. Analysis of the backbone chemical shifts demonstrates that the secondary structure of VNAR is predominately composed of β-sheets corresponding to around 40% of the B2-3 backbone. The Cβ chemical shift values of cysteine residues, combined with mass spectrometry data, clearly shows that B2-3 contains two pairs of disulfide bonds, which is import for protein stability. The assignments will be essential for determining the high resolution solution structure of B2-3 by NMR spectroscopy.

Advances of monoclonal antibodies and analysis of marketed antibody drugs

In recent years, there has been a frequent occurrence of various epidemics worldwide such as COVID-19, monkeypox, influenza, and others additionally, there has been an increase in the number of new patients diagnosed with various types of tumors. Traditional drugs have limited effectiveness against emerging infectious diseases, tumors, and autoimmune diseases. However, with the emergence of hybridoma technology, monoclonal antibodies have achieved extensive applications and antibody drugs are playing an important role in modern medicine. Monoclonal antibodies have undergone various development stages, starting from mouse-derived antibodies to human-mouse chimeric antibodies, humanized antibodies, and ultimately human antibodies. Throughout this process, their immunogenicity has gradually decreased, while their safety for human use steadily increased. Fully human antibodies are currently the safest form of antibody, because their sequences all come from human sources and they do not induce human anti-murine antibody reactions. With the advance of genetic engineering technology, flow cytometry coupled to single B cell gene amplification technology has made it easier to construct and screen for fully human monoclonal antibodies. The development of antibody drugs has provided new opportunities, and the market for monoclonal antibody drugs will further expand. This article reviews the research progress of monoclonal antibodies and presents information on the 163 monoclonal antibody drugs approved by the United States Food and Drug Administration (FDA) as of Oct 1st, 2023. The aim is to offer new insights for the development and production of monoclonal antibodies in China.

Druggability properties of a L309K mutation in the antibody CH2 domain.

In the early stages of antibody drug development, it is imperative to conduct a comprehensive assessment and enhancement of the druggability attributes of potential molecules by considering their fundamental physicochemical properties. This study specifically concentrates on the surface-exposed hydrophobic region of the candidate antibody aPDL1-WT and explores the effectiveness of the L309K mutation strategy. The resulting aPDL1-LK variant demonstrates a notable enhancement over the original antibody in addressing the issue of aggregation and formation of large molecular impurities under accelerated high-temperature conditions. The mutated molecule, aPDL1-LK, exhibits excellent physicochemical properties such as hydrophilicity, conformational stability, charge variant stability, post-translational modifications, and serum stability. In terms of biological function, aPDL1-LK maintains the same glycosylation pattern as the original antibody and shows no significant difference in affinity for antigen hPDL1 protein, CD16a-F158, CD64, CD32a-H131, and complement C1q, compared to aPDL1-WT. The L309K mutation results in an approximately twofold reduction in its affinity for CD16a-V158 and CD32a-R131. In vitro biological assays, including antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement-dependent cytotoxicity (CDC), reveal that the L309K mutation may decrease CD16a-V158-mediated ADCC activity due to the mutation-induced decrease in ligand affinity, while not affect CD32a-R131-mediated ADCP activity. In conclusion, the L309K mutation offers a promising strategy to enhance the druggability properties of candidate antibodies.

Sensing antibody functions with a novel CCR8-responsive engineered cell.

Human chemokine receptor 8 (CCR8) is a promising drug target for immunotherapy of cancer and autoimmune diseases. Monoclonal antibody-based CCR8 targeted treatment shows significant inhibition in tumor growth. The inhibition of CCR8 results in the improvement of antitumor immunity and patient survival rates by regulating tumor-resident regulatory T cells. Recently monoclonal antibody drug development targeting CCR8 has become a research hotspot, which also promotes the advancement of antibody evaluation methods. Therefore, we constructed a novel engineered customized cell line HEK293-cAMP-biosensor-CCR8 combined with CCR8 and a cAMP-biosensor reporter. It can be used for the detection of anti-CCR8 antibody functions like specificity and biological activity, in addition to the detection of antibody-dependent cell-mediated cytotoxicity and antibody-dependent-cellular-phagocytosis. We obtained a new CCR8 mAb 22H9 and successfully verified its biological activities with HEK293-cAMP-biosensor-CCR8. Our reporter cell line has high sensitivity and specificity, and also offers a rapid kinetic detection platform for evaluating anti-CCR8 antibody functions.

Long-Acting Strategies for Antibody Drugs: Structural Modification, Controlling Release, and Changing the Administration Route.

Because of their high specificity, high affinity, and targeting, antibody drugs have been widely used in the treatment of many diseases and have become the most favored new drugs for research in the world. However, some antibody drugs (such as small-molecule antibody fragments) have a short half-life and need to be administered frequently, and are often associated with injection-site reactions and local toxicities during use. Increasing attention has been paid to the development of antibody drugs that are long-acting and have fewer side effects. This paper reviews existing strategies to achieve long-acting antibody drugs, including modification of the drug structure, the application of drug delivery systems, and changing their administration route. Among these, microspheres have been studied extensively regarding their excellent tolerance at the injection site, controllable loading and release of drugs, and good material safety. Subcutaneous injection is favored by most patients because it can be quickly self-administered. Subcutaneous injection of microspheres is expected to become the focus of developing long-lasting antibody drug strategies in the near future.

Abstract 724: MPSA-AB5000: A high-throughput membrane proteins screening array for therapeutic biologics specificity profiling

Abstract The development of novel antibody drugs is a lengthy journey. Many factors can lead to failures during clinical development. According to reports, off-target binding of antibodies could also be a significant cause. It has been stated that about 25% of preclinical candidates might have off-target issues. With the emergence of new modalities like CD3 bispecific antibodies, ADCs, and CAR-T therapies, early-stage off-target screening of antibodies has become even more crucial. Although techniques such as immunohistochemistry, ELISA, and flow cytometry (FACS) have been used for off-target testing of antibodies, these methods still lack sensitivity and specificity, and their throughput is limited. To address the need for antibody target deconvolution and receptor identification, we developed a novel membrane protein screening array-AB5000 (MPSA-AB5000). MPSA-AB5000 is a high-throughput cell-based platform for identifying the targets of antibodies and other ligands that bind to membrane proteins. MPSA-AB5000 is an excellent solution for antibody specificity screening, which enables early off-target screening and can de-risk the antibody drug development program. The MPSA-AB5000 makes use of the full coverage of unique human membrane proteins, including receptors, transporters, enzymes, miscellaneous, and others. Each membrane protein is expressed in live cells to ensure native conformation. In addition, the same membrane protein clones with a C-terminal epitope tag were constructed, allowing confirmation of protein expression and cellular location. To provide the highest level of sensitivity, MPSA-AB5000 uses luciferase reporter cell line detection. The wash-free strategy reduces false negatives, and signal amplification makes remarkable discrimination. Compared to similar technologies, we possess significant advantages in the following aspects: a. High sensitivity and sigh throughput: our technology platform offers not only high sensitivity, capable of detecting subtle interactions but also supports high-throughput screening, allowing for the evaluation of a large number of samples in a short timeframe. b. Avoidance of false negative signals: by eliminating washing steps, our method reduces the risk of false negative signals, ensuring reliable detection of non-specific binding. c. Comprehensive validation approaches: We employ various validation methods such as FACS and ELISA to eliminate false positive signals and enhance the accuracy and credibility of our results. All the advantages ensure that MPSA-AB5000 is more rapid, simple, and highly sensitive than traditional assays. Citation Format: dan Li, Junyi Xiong, Jinying Ning, Feng Hao. MPSA-AB5000: A high-throughput membrane proteins screening array for therapeutic biologics specificity profiling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 724.

Abstract 5333: NeoMab: A novel platform for fully human therapeutic antibody development

Abstract Antibodies and antibody containing therapeutics, such as multivalent antibodies, chimeric antigen receptors (CARs), and antibody directed conjugates (ADCs), have been proven to be highly prominent in cancer treatment. However, challenges such as immunogenicity stemming from non-human or unnatural sequences and limitations in preclinical animal study systems still impede the rapid development of antibody drugs. To overcome these hurdles, GemPharmatech has created a novel antibody gene humanized model, the NeoMab mouse, to develop fully human antibodies. The NeoMab model was established via large genomic fragment knock-in technology, retaining native mouse constant region encoding genes and regulatory elements, while incorporating human variable gene repertoires into the endogenous loci. Developed in the BALB/c background, the NeoMab mouse carries fully functional MHC molecules, potentially enhancing antigen presentation. These mice sustain a competent immune system with a B cell development and maturation pattern, immune cell profile, and serum immunoglobulin levels comparable to those of BALB/c mice. NeoMab mice exhibit a robust humoral immune response, with a rapid increase in antigen-specific serum titers upon immunization using different antigens, such as recombined protein, plasmids, and overexpressing cell lines. Utilizing human V(D)J genes to encode immunoglobulins at a human-like frequency and diversity, antibodies derived from NeoMab mice demonstrate affinity and functional activity comparable to, or even surpassing, FDA-approved drugs. In conclusion, the NeoMab mouse model in the BALB/c background has been rigorously validated to elicit a robust response to specific antigen immunization, producing antibodies with high affinity, diversity, and functional activity. GemPharmatech's extensive drug-target gene humanized mouse library (comprising over 800 targets) and diverse disease models in oncology and other fields facilitate a seamless connection between in vitro antibody screening and in vivo animal studies. The integration of NeoMab, target humanization animals, and disease models enables GemPharmatech to provide an integrated solution, reducing time and costs while elevating the quality of antibody discovery in the field. Citation Format: Mingkun Zhang, Cunxiang Ju, Song Li, Junchao Peng, Jing Zhao, Xiang Gao. NeoMab: A novel platform for fully human therapeutic antibody development [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5333.

NanoBERTa-ASP: predicting nanobody paratope based on a pretrained RoBERTa model

BackgroundNanobodies, also known as VHH or single-domain antibodies, are unique antibody fragments derived solely from heavy chains. They offer advantages of small molecules and conventional antibodies, making them promising therapeutics. The paratope is the specific region on an antibody that binds to an antigen. Paratope prediction involves the identification and characterization of the antigen-binding site on an antibody. This process is crucial for understanding the specificity and affinity of antibody-antigen interactions. Various computational methods and experimental approaches have been developed to predict and analyze paratopes, contributing to advancements in antibody engineering, drug development, and immunotherapy. However, existing predictive models trained on traditional antibodies may not be suitable for nanobodies. Additionally, the limited availability of nanobody datasets poses challenges in constructing accurate models.MethodsTo address these challenges, we have developed a novel nanobody prediction model, named NanoBERTa-ASP (Antibody Specificity Prediction), which is specifically designed for predicting nanobody-antigen binding sites. The model adopts a training strategy more suitable for nanobodies, based on an advanced natural language processing (NLP) model called BERT (Bidirectional Encoder Representations from Transformers). To be more specific, the model utilizes a masked language modeling approach named RoBERTa (Robustly Optimized BERT Pretraining Approach) to learn the contextual information of the nanobody sequence and predict its binding site.ResultsNanoBERTa-ASP achieved exceptional performance in predicting nanobody binding sites, outperforming existing methods, indicating its proficiency in capturing sequence information specific to nanobodies and accurately identifying their binding sites. Furthermore, NanoBERTa-ASP provides insights into the interaction mechanisms between nanobodies and antigens, contributing to a better understanding of nanobodies and facilitating the design and development of nanobodies with therapeutic potential.ConclusionNanoBERTa-ASP represents a significant advancement in nanobody paratope prediction. Its superior performance highlights the potential of deep learning approaches in nanobody research. By leveraging the increasing volume of nanobody data, NanoBERTa-ASP can further refine its predictions, enhance its performance, and contribute to the development of novel nanobody-based therapeutics.Github repository: https://github.com/WangLabforComputationalBiology/NanoBERTa-ASP

Antibody druggability screening process and evaluation strategy

Since the approval of OKT3 as the first therapeutic monoclonal antibody in 1986, there has been rapid development in antibody technology and antibody drugs. Monoclonal antibodies, antibody fragments, bi (multi) specific antibodies, fusion proteins, nanobodies, and antibody-drug conjugates (ADCs) have been introduced and play a significant role in the treatment of oncology, hematology, immunology, respiratory, metabolic and other related diseases. The process of antibody drug discovery involves multiple rounds of biological function and druggability assessments to identify the best candidate sequences that are safe, effective, stable, and scalable. This lays the foundation for the efficiency and success of drug development and clinical studies. In the phase of antibody drug discovery, "druggability screening and evaluation" has received increasing attention. It involves drug discovery and design, screening and optimization of lead molecules as well as the validation of candidate molecules, with the aim of detecting potential physicochemical risk factors and evaluating controllability to ensure the quality stability of the subsequent drug development process. This paper classifies and defines the process of druggability screening and evaluation in the antibody discovery phase, covering monoclonal antibodies, bispecific antibodies, nanobodies, ADCs and other related technologies and drug forms. It also summarizes the quality attributes and high-throughput detection technology that should be emphasized in the druggability screening and evaluation. The systematic elaboration of the druggability development process and strategy provides a reference for the druggability screening and evaluation of emerging innovative drugs, significantly improving the efficiency and success rate of antibody drug development.

Potent and broadly neutralizing antibodies against sarbecoviruses induced by sequential COVID-19 vaccination

The current SARS-CoV-2 variants strikingly evade all authorized monoclonal antibodies and threaten the efficacy of serum-neutralizing activity elicited by vaccination or prior infection, urging the need to develop antivirals against SARS-CoV-2 and related sarbecoviruses. Here, we identified both potent and broadly neutralizing antibodies from a five-dose vaccinated donor who exhibited cross-reactive serum-neutralizing activity against diverse coronaviruses. Through single B-cell sorting and sequencing followed by a tailor-made computational pipeline, we successfully selected 86 antibodies with potential cross-neutralizing ability from 684 antibody sequences. Among them, PW5-570 potently neutralized all SARS-CoV-2 variants that arose prior to Omicron BA.5, and the other three could broadly neutralize all current SARS-CoV-2 variants of concern, SARS-CoV and their related sarbecoviruses (Pangolin-GD, RaTG13, WIV-1, and SHC014). Cryo-EM analysis demonstrates that these antibodies have diverse neutralization mechanisms, such as disassembling spike trimers, or binding to RBM or SD1 to affect ACE2 binding. In addition, prophylactic administration of these antibodies significantly protects nasal turbinate and lung infections against BA.1, XBB.1, and SARS-CoV viral challenge in golden Syrian hamsters, respectively. Importantly, post-exposure treatment with PW5-5 and PW5-535 also markedly protects against XBB.1 challenge in these models. This study reveals the potential utility of computational process to assist screening cross-reactive antibodies, as well as the potency of vaccine-induced broadly neutralizing antibodies against current SARS-CoV-2 variants and related sarbecoviruses, offering promising avenues for the development of broad therapeutic antibody drugs.

RECENT ACHIEVEMENTS IN THE STUDY OF PATHOMECHANISMS OF RHYNOSINUSITIS ASSOCIATED WITH NON-STEROID ANTI-INFLAMMATORS INTOLERANCE (literature review)

Background. The pathomechanism of rhinosinusitis associated with the use of non-steroidal anti-inflammatory drugs is complex and still not fully understood. They are now known to be associated with genetic predisposition and environmental triggers that lead to dysregulation of fatty acid and lipid metabolism, cell transmetabolism, and chronic inflammation in the airways.
 Aim: analysis of recent advances in the study of aspirin-associated respiratory disease (AERD), summarization of already known information about the pathomechanisms of the disease.
 Materials and methods. The analysis of literary sources included publications in the international electronic scientometric databases PubMed, Scopus, Web of Science by keywords for the period 2013-2023. 46 sources were selected for analysis, of which 24 were used that met the search criteria.
 Results. The results showed that researchers are actively studying the role of immunological factors, particularly IgG4 and IgE in the pathogenesis of the disease. IgG4 was detected in nasal polyp tissue and associated with poor postoperative outcome, which may indicate its important role in chronic sinusitis. In addition, cytokines such as thymic stromal lymphopoietin, IL-4, IL-10, IL-5, IL-13, and IL-33 have been detected in eosinophilic nasal polyps in patients with aspirin intolerance, suggesting their possible role in the development AERD.
 Conclusion. The cause of severe nasal polyposis in AERD has not been definitively determined. Further research may lead to the development of more personalized treatments. Dietary modification and development of new monoclonal antibody drugs lead to reduction of AERD symptoms and improvement of patients' quality of life.

The Research Progress on Immortalization of Human B Cells.

Human B cell immortalization that maintains the constant growth characteristics and antibody expression of B cells in vitro is very critical for the development of antibody drugs and products for the diagnosis and bio-therapeutics of human diseases. Human B cell immortalization methods include Epstein-Barr virus (EBV) transformation, Simian virus 40 (SV40) virus infection, in vitro genetic modification, and activating CD40, etc. Immortalized human B cells produce monoclonal antibodies (mAbs) very efficiently, and the antibodies produced in this way can overcome the immune rejection caused by heterologous antibodies. It is an effective way to prepare mAbs and an important method for developing therapeutic monoclonal antibodies. Currently, the US FDA has approved more than 100 mAbs against a wide range of illnesses such as cancer, autoimmune diseases, infectious diseases, and neurological disorders. This paper reviews the research progress of human B cell immortalization, its methods, and future directions as it is a powerful tool for the development of monoclonal antibody preparation technology.

Design, synthesis and bioactivity evaluation of novel fusion peptides and their CPT conjugates inducing effective anti-tumor responses on HER2 positive tumors

Human epidermal growth factor receptor 2 (HER2) represents an ideal target for antibody drug development, abnormal expression of the HER2 gene is associated with multiple tumor types. Pertuzumab, as the first monoclonal antibody inhibitor of HER2 dimerization, has been FDA-approved for HER2-positive patients. In order to enhance the activity of HER2-targeted peptide-drug conjugates (PDCs) developed based on pertuzumab, a novel class of conjugates 1–9 was designed and synthesized by fusing the N-terminal peptide sequence of the second mitochondria-derived activator of caspases (SMAC) with P1, followed by conjugation with CPT molecules. Compound 4 exhibited excellent in vitro anti-tumor activity across the three HER2-positive cell lines, comparable to the activity of CPT. Apoptosis induction assays indicated that the synergistic effect of the SMAC sequence enhanced the pro-apoptotic activity of the conjugate. Western Blot analysis and Caspase activity studies validated the mechanism through which SMAC peptides, in synergy with CPT, enhance the activity of PDCs. In vivo studies demonstrated that compound 4 possesses superior anti-tumor activity compared to CPT and can effectively mitigate potential renal toxicity associated with free SMAC peptides. In conclusion, conjugate 4 exhibited excellent anti-tumor activity both in vitro and in vivo, offering potential for further development as a novel peptide-conjugated drug.

A transmembrane scaffold from CD20 helps recombinant expression of a chimeric claudin 18.2 in an in vitro coupled transcription and translation system

Cluster of differentiation 20 (CD20) is a nonglycosylated, multispanning transmembrane protein specifically integrated by B lymphocytes. Similar to CD20, another four-pass transmembrane protein, claudin 18.2, has attracted attention as an emerging therapeutic target for cancer. However, their poor solubility and toxic nature often hinder downstream applications, such as antibody drug development. Therefore, developing a cost-effective method for producing drug targets with multiple membrane-spanning domains is crucial. In this study, a high yield of recombinant CD20 was achieved through an E. coli–based in vitro coupled transcription–translation system. Surface plasmon resonance results showed that rituximab (an antileukemia drug) has nanomolar affinity with the CD20 protein, which aligns with published results. Notably, a previously hard-to-express claudin 18.2 recombinant protein was successfully expressed in the same reaction system by replacing its membrane-spanning domains with the transmembrane domains of CD20. The folding of the extracellular domain of the chimeric protein was verified using a commercial anti-claudin 18 antibody. This study provides a novel concept for promoting the expression of four-pass transmembrane proteins and lays the foundation for the large-scale industrial production of membrane-associated drug targets, similar to claudin 18.2.

Deep learning in preclinical antibody drug discovery and development.

Antibody drugs have become a key part of biotherapeutics. Patients suffering from various diseases have benefited from antibody therapies. However, its development process is rather long, expensive and risky. To speed up the process, reduce cost and improve success rate, artificial intelligence, especially deep learning methods, have been widely used in all aspects of preclinical antibody drug development, from library generation to hit identification, developability screening, lead selection and optimization. In this review, we systematically summarize antibody encodings, deep learning architectures and models used in preclinical antibody drug discovery and development. We also critically discuss challenges and opportunities, problems and possible solutions, current applications and future directions of deep learning in antibody drug development.

FULLY AI-DRIVEN HUMANOID VHH PHAGE LIBRARY

Abstract Background & Significance VHHs are small and stable fragments that have great potential as therapeutics due to their small size, stability, versatility, and potential for oral administration. The traditional source of VHHs is camelids, but humanization is usually needed for therapeutic development. A human VHH library is highly desirable for the generation of therapeutic VHHs, but natural human VH domains are usually unstable as standalone units. We developed a humanoid VHH library of AI-designed sequences that both resemble camelid VHHs in terms of stability and have such high human content that humanization is no longer needed. Methods In this study, we present a fully AI-driven approach for the de novo design of a VHH phage library. Firstly, public camelid data and nearly one million private human sequences were collected. Secondly, one autoregressive AI model was trained on human data and another AI model was trained on the mixed data of humans and camels. Thirdly, the CDR1, CDR2, CDR3 regions of VHH were all generated by the mentioned two AI models. Finally, an ultra large quantity (4E10) of VHH sequences generated by AI were utilized to build the Humanoid VHH phage library. Results In order to verify the effectiveness of our method, we randomly synthesized and expressed 26 VHH antibodies from our AI based library. At the same time, 3 human VH molecules reported in previous literature were included as positive controls. First of all, the success rate of expression is 96.1%, which is much higher than 72% of Progen and 66% of ESMdesign. Secondly, the average titer is 59.6mg/L, which is 1.5 times the average value of the positive control group. Thirdly, the hydrophobicity of 80% de novo sequences is comparable to the positive control group. Moreover, the immunogenicity of all AI sequences is less than the average value of the positive control group according to our proprietary algorithms. Finally, the diversity and naturalness of the Humanoid VHH phage library are also excellent. Conclusions In conclusion, we have developed a fully AI-driven solution that could stably and massively generate human-like VHH sequences satisfying multiple requirements (including high titer, low hydrophobicity, low immunogenicity and ultra high success rate of expression, high diversity, high naturalness) simultaneously. As VHH is a powerful therapeutic fragment, our approach has the potential to accelerate nanobody and bispecific antibody drug development.

Receptor-mediated drug delivery of bispecific therapeutic antibodies through the blood-brain barrier.

Therapeutic antibody drug development is a rapidly growing sector of the pharmaceutical industry. However, antibody drug development for the brain is a technical challenge, and therapeutic antibodies for the central nervous system account for ~3% of all such agents. The principal obstacle to antibody drug development for brain or spinal cord is the lack of transport of large molecule biologics across the blood-brain barrier (BBB). Therapeutic antibodies can be made transportable through the blood-brain barrier by the re-engineering of the therapeutic antibody as a BBB-penetrating bispecific antibody (BSA). One arm of the BSA is the therapeutic antibody and the other arm of the BSA is a transporting antibody. The transporting antibody targets an exofacial epitope on a BBB receptor, and this enables receptor-mediated transcytosis (RMT) of the BSA across the BBB. Following BBB transport, the therapeutic antibody then engages the target receptor in brain. RMT systems at the BBB that are potential conduits to the brain include the insulin receptor (IR), the transferrin receptor (TfR), the insulin-like growth factor receptor (IGFR) and the leptin receptor. Therapeutic antibodies have been re-engineered as BSAs that target the insulin receptor, TfR, or IGFR RMT systems at the BBB for the treatment of Alzheimer's disease and Parkinson's disease.

Abalign: a comprehensive multiple sequence alignment platform for B-cell receptor immune repertoires.

The utilization of high-throughput sequencing (HTS) for B-cell receptor (BCR) immune repertoire analysis has become widespread in the fields of adaptive immunity and antibody drug development. However, the sheer volume of sequences generated by these experiments presents a challenge in data processing. Specifically, multiple sequence alignment (MSA), a critical aspect of BCR analysis, remains inadequate for handling massive BCR sequencing data and lacks the ability to provide immunoglobulin-specific information. To address this gap, we introduce Abalign, a standalone program specifically designed for ultrafast MSA of BCR/antibody sequences. Benchmark tests demonstrate that Abalign achieves comparable or even better accuracy than state-of-the-art MSA tools, and shows remarkable advantages in terms of speed and memory consumption, reducing the time required for high-throughput analysis from weeks to hours. In addition to its alignment capabilities, Abalign offers a broad range of BCR analysis features, including extracting BCRs, constructing lineage trees, assigning VJ genes, analyzing clonotypes, profiling mutations, and comparing BCR immune repertoires. With its user-friendly graphic interface, Abalign can be easily run on personal computers instead of computing clusters. Overall, Abalign is an easy-to-use and effective tool that enables researchers to analyze massive BCR/antibody sequences, leading to new discoveries in the field of immunoinformatics. The software is freely available at http://cao.labshare.cn/abalign/.

The Screening of Broadly Neutralizing Antibodies Targeting the SARS-CoV-2 Spike Protein by mRNA Immunization in Mice.

Neutralizing antibodies (nAbs), the popular antiviral drugs used for the treatment of COVID-19, are effective in reducing viral load and hospitalization. Currently, most nAbs are screened from convalescent or vaccinated individuals through single B-cell sequencing which requires cutting-edge facilities. Moreover, owing to the rapid mutation of SARS-CoV-2, some approved nAbs are no longer effective. In the present study, we designed a new approach to acquiring broadly neutralizing antibodies (bnAbs) from mRNA-vaccinated mice. Using the flexibility and speed of mRNA vaccine preparation, we designed a chimeric mRNA vaccine and sequential immunization strategies to acquire bnAbs in mice within a short period. By comparing different vaccination orders, we found that the initially administered vaccine had a greater effect on the neutralizing potency of mouse sera. Ultimately, we screened a strain of bnAb that neutralized wild-type, Beta, and Delta SARS-CoV-2 pseudoviruses. We synthesized the mRNAs of the heavy and light chains of this antibody and verified its neutralizing potency. This study developed a new strategy to screen for bnAbs in mRNA-vaccinated mice and identified a more effective immunization strategy for inducing bnAbs, providing valuable insights for future antibody drug development.

Design and optimization of mRNAs encoding an Anti-TIGIT antibody with therapeutic potential for cancer in TIGIT-humanized BALB/c Mice

mRNA drugs are synthesized using cell-free systems without complex and stringent manufacturing processes, which makes their preparation simple, efficient, and economical. Over the past few years, mRNAs encoding antibodies have been one of the research frontiers of antibody drug development. In cancer immunotherapy, mRNAs encoding immune checkpoint antibodies may be advantageous regarding antibody persistence and durability of the anti-tumor immune response of patients. In our previous study, a candidate antibody—AET2010—targeting the novel immune checkpoint TIGIT was reported. Its anti-tumor activity was also investigated using adoptive transfer of NK-92MI cells in a xenograft mouse model, but the limitations of the model did not facilitate precise evaluation. In the present study, we further investigated the therapeutic potential of AET2010 for cancer in TIGIT-humanized BALB/c mice. Next, we explored the design, synthesis, and optimization of mRNAs encoding AET2010 and ultimately obtained a candidate mRNA (mRNA-BU) with favorable in vitro and in vivo expression levels of active AET2010. Particularly, lipid-nanoparticle-encapsulated mRNA-BU delivered to mice produced AET2010 with significantly higher peak concentration and expression duration than an equivalent dose of original AET2010. This study provides a sound basis for developing novel drugs targeting TIGIT.