Monoclonal Antibodies: Past, Present and Future

A paradigm use of monoclonal antibodies-conjugated nanoparticles in breast cancer treatment: current status and potential approaches

Monoclonal antibodies (mAbs) are integral to cancer treatment over conventional non-specific therapy methods. This study provides a scoping review of the clinically approved mAbs, focusing on the current application of different nanocarrier technologies as drug delivery targets for mAb-conjugated nanoparticles (NPs) as potential features for breast cancer (BC) treatment. An extensive literature search was conducted between the years 2000 and 2023 using various sources of databases. The first part covered mAb classification, types, and mechanisms of action, pharmacokinetics and clinical applications in BC. The second part covered polymeric, lipid and inorganic-based NPs, which are a variety of mAb-conjugated NPs targeting BC. A total of 20 relevant studies were enrolled indicating there are three different types of nanoparticular systems (polymeric NPs, inorganic NPs and lipid-based NPs) that can be used for BC treatment by being loaded with various active substances and conjugated with these antibodies. While mAbs have altered the way in cancer treatment due to targeting cancer cells specifically, the delivery of mAbs with nanoparticulate systems is important in the treatment of BC, as NPs are still being investigated as distinctive and promising drug delivery methods that can be employed for effective treatment of BC.

Rapid analysis of amatoxins in human urine by means of affinity column chromatography and liquid chromatography-high-resolution tandem mass spectrometry

Analysis of amatoxins is of great importance as these cyclic peptides contribute to a high number of fatalities each year. Development of analytical approaches needs to focus on rapid, sensitive, and reliable methods. By establishing an affinity column chromatography-based assay using the monoclonal amanitin antibody AMA9G3 and liquid chromatography (LC) coupled to high-resolution mass spectrometry (HRMS) for the trace detection of α-, β-, and γ-amanitin in human urine samples to confirm ingestion, we report the first approach that extents the current status of amatoxin analysis. The presented procedure allows detection of amatoxins in human urine down to 1 ng/mL. The method was successfully validated qualitatively for α- and γ-amanitin according to international recommendations. A proof of concept was performed by analyzing 37 urine samples after suspected amatoxin consumption submitted for regular clinical toxicological analysis. Using this antibody-based enrichment strategy, acute amatoxin intoxications can be determined within 90 min and due to the high sensitivity and selectivity, a comparable approach using target specific antibodies may also be used for other toxicological relevant peptides.

Charge Variants Characterization of Co-Formulated Antibodies by Three-Dimensional Liquid Chromatography-Mass Spectrometry

Co-formulated antibodies can bring clinical benefits to patients by combining two or more antibodies in a single dosage form. However, the quality analysis of co-formulated antibodies raises additional challenges, compared to individual antibodies, due to the need for accurate analysis of multiple antibodies in one solution. It is extremely difficult to effectively separate the charge variants of the two co-formulated antibodies using one ion exchange chromatography (IEC) method because of their similar characteristics. In this study, a novel method was developed for the charge variants characterization of co-formulated antibodies using three-dimensional liquid chromatography-mass spectrometry (3D-LC-MS). Hydrophobic interaction chromatography (HIC) was used as the first dimension to separate and collect the two co-formulated antibodies. The two collections were then injected into the second-dimension IEC separately for charge variants separation and analysis. Subsequently, the separated charge variants underwent on-line desalting in the third-dimension reverse-phase chromatography (RPC) and subsequent mass spectroscopy analysis. The novel method could simultaneously provide a charge variants ratio and post-translational modification (PTM) data for the two co-formulated antibodies. Therefore, it could be used for release testing and stability studies of co-formulated antibodies, making up for the shortcomings of the existing approaches. It was the first time that charge variants of co-formulated antibodies were characterized by the 3D-LC-MS method, to the best of our knowledge.

Dawn of CAR-T cell therapy in autoimmune diseases

ABSTRACT

Chimeric antigen receptor (CAR)-T cell therapy has achieved remarkable success in the treatment of hematological malignancies. Based on the immunomodulatory capability of CAR-T cells, efforts have turned toward exploring their potential in treating autoimmune diseases. Bibliometric analysis of 210 records from 128 academic journals published by 372 institutions in 40 countries/regions indicates a growing number of publications on CAR-T therapy for autoimmune diseases, covering a range of subtypes such as systemic lupus erythematosus, multiple sclerosis, among others. CAR-T therapy holds promise in mitigating several shortcomings, including the indiscriminate suppression of the immune system by traditional immunosuppressants, and non-sustaining therapeutic levels of monoclonal antibodies due to inherent pharmacokinetic constraints. By persisting and proliferating in vivo , CAR-T cells can offer a tailored and precise therapeutics. This paper reviewed preclinical experiments and clinical trials involving CAR-T and CAR-related therapies in various autoimmune diseases, incorporating innovations well-studied in the field of hematological tumors, aiming to explore a safe and effective therapeutic option for relapsed/refractory autoimmune diseases.

Ocular side effects of oncological therapies: Review

With the advance of cancer therapy in recent years, the knowledge of the mechanisms involved in this disease has increased, which has meant an increase in the quality of life and survival of patients with tumor pathologies previously considered incurable or refractory to treatment. The number of drugs used has increased exponentially in number, and although the implicit toxicity is lower than that of conventional antineoplastic therapy, they lead to the appearance of new associated adverse effects that the ophthalmologist must recognize and manage.

Monoclonal antibodies for dyslipidemia in adults: a focus on vulnerable patients groups

INTRODUCTION

Dyslipidemia significantly contributes to atherosclerotic cardiovascular disease (ASCVD). Patients with lipid-rich vulnerable plaques are particularly susceptible to cardiovascular complications. Despite available lipid-lowering therapies (LLTs), challenges in effective lipid management remain.

AREAS COVERED

This article reviews monoclonal antibody (mAb) therapy in dyslipidemia, particularly focusing on vulnerable plaques and patients. We have reviewed the definitions of vulnerable plaques and patients, outlined the efficacy of traditional LLTs, and discussed in-depth the mAbs targeting PCSK9. We extensively discuss the potential mechanisms, intracoronary imaging, and clinical evidence of PCSK9mAbs in vulnerable plaques and patients. A brief overview of promising mAbs targeting other targets such as ANGPTL3 is also provided.

EXPERT OPINION

Research consistently supports the potential of mAb therapies in treating adult dyslipidemia, particularly in vulnerable patients. PCSK9mAbs are effective in regulating lipid parameters, such as LDL-C and Lp(a), and exhibit anti-inflammatory and anti-thrombotic properties. These antibodies also maintain endothelial and smooth muscle health, contributing to the stabilization of vulnerable plaques and reduction in adverse cardiovascular events. Future research aims to further understand PCSK9 and other targets like ANGPTL3, focusing on vulnerable groups. Overall, mAbs are emerging as a promising and superior approach in dyslipidemia management and cardiovascular disease prevention.

Recent applications of RNA therapeutic in clinics

Ribonucleic acid (RNA) therapy has been extensively researched for several decades and has garnered significant attention in recent years owing to its potential in treating a broad spectrum of diseases. It falls under the domain of gene therapy, leveraging RNA molecules as a therapeutic approach in medicine. RNA can be targeted using small-molecule drugs, or RNA molecules themselves can serve as drugs by interacting with proteins or other RNA molecules. While several RNA drugs have been granted clinical approval, numerous RNA-based therapeutics are presently undergoing clinical investigation or testing for various conditions, including genetic disorders, viral infections, and diverse forms of cancer. These therapies offer several advantages, such as high specificity, enabling precise targeting of disease-related genes or proteins, cost-effectiveness, and a relatively straightforward manufacturing process. Nevertheless, successful translation of RNA therapies into widespread clinical use necessitates addressing challenges related to delivery, stability, and potential off-target effects. This chapter provides a comprehensive overview of the general concepts of various classes of RNA-based therapeutics, the mechanistic basis of their function, as well as recent applications of RNA therapeutic in clinics.

Recent Advances in the Development of Monoclonal Antibodies and Next-Generation Antibodies

mAbs are highly indispensable tools for diagnostic, prophylactic, and therapeutic applications. The first technique, hybridoma technology, was based on fusion of B lymphocytes with myeloma cells, which resulted in generation of single mAbs against a specific Ag. Along with hybridoma technology, several novel and alternative methods have been developed to improve mAb generation, ranging from electrofusion to the discovery of completely novel technologies such as B cell immortalization; phage, yeast, bacterial, ribosome, and mammalian display systems; DNA/RNA encoded Abs; single B cell technology; transgenic animals; and artificial intelligence/machine learning. This commentary outlines the evolution, methodology, advantages, and limitations of various mAb production techniques. Furthermore, with the advent of next-generation Ab technologies such as single-chain variable fragments, nanobodies, bispecific Abs, Fc-engineered Abs, Ab biosimilars, Ab mimetics, and Ab-drug conjugates, the healthcare and pharmaceutical sectors have become resourceful to develop highly specific mAb treatments against various diseases such as cancer and autoimmune and infectious diseases.

DG-Affinity: predicting antigen-antibody affinity with language models from sequences

BACKGROUND

Antibody-mediated immune responses play a crucial role in the immune defense of human body. The evolution of bioengineering has led the progress of antibody-derived drugs, showing promising efficacy in cancer and autoimmune disease therapy. A critical step of this development process is obtaining the affinity between antibodies and their binding antigens.

RESULTS

In this study, we introduce a novel sequence-based antigen-antibody affinity prediction method, named DG-Affinity. DG-Affinity uses deep neural networks to efficiently and accurately predict the affinity between antibodies and antigens from sequences, without the need for structural information. The sequences of both the antigen and the antibody are first transformed into embedding vectors by two pre-trained language models, then these embeddings are concatenated into an ConvNeXt framework with a regression task. The results demonstrate the superiority of DG-Affinity over the existing structure-based prediction methods and the sequence-based tools, achieving a Pearson's correlation of over 0.65 on an independent test dataset.

CONCLUSIONS

Compared to the baseline methods, DG-Affinity achieves the best performance and can advance the development of antibody design. It is freely available as an easy-to-use web server at https://www.digitalgeneai.tech/solution/affinity .

A Case Report of Adalimumab Successfully Treated a Severe Plaque Psoriasis Patient with Psoriatic End-Stage Renal Disease

Psoriasis is a common chronic inflammatory skin disease that manifests itself not only on the skin but also on various tissues and organs of the body. While some psoriasis co-morbidities have been investigated, little is known about its association with impairment of renal function. In 2005, the concept of psoriatic nephropathy was first introduced by Indian nephrologists, suggesting a potential relationship between psoriasis and kidney disease. Adalimumab, a fully human recombinant immunoglobulin G1 monoclonal antibody against tumor necrosis factor (TNF)-α, has been shown to be a safe and effective treatment for patients with moderate to severe psoriasis. Here, we present a case of severe plaque psoriasis accompanied with end-stage renal disease (ESRD) treated with adalimumab. Following the case presentation is a discussion of the relationship between psoriasis and chronic kidney disease (CKD) / ESRD and the possible role of biologics in psoriasis-related kidney damage. The aim of this report is to increase dermatologists' awareness of psoriatic nephropathy as a complication of psoriasis and to raise awareness of the use of biologics in psoriasis.

An MMAE-loaded PDL1 active targeting nanomedicine for the precision treatment of colon cancer

Tumor-active-targeting drugs such as antibody-drug conjugates have emerged as promising accurate therapeutic agents. However, their complex preparations risk compromising the targeting ability of the fragment antigen binding (Fab) region and promote aggregation over long-term storage. Here, we propose a tumor-active-targeting nanomedicine, aPDL1-PLG-MMAE, that effectively targets programmed death-ligand 1 (PDL1) high-expressing tumors and delivers monomethyl auristatin E (MMAE). aPDL1-PLG-MMAE consists of an anti-PDL1 monoclonal antibody (aPDL1) and poly(L-glutamic acid) (PLG) grafted Fc-III-4C peptide/Val-Cit-PAB-MMAE (Fc-PLG-MMAE). Fc-PLG-MMAE was obtained by conjugating the Fc-III-4C peptide and Val-Cit-PAB-MMAE to PLG via amide condensation. The strong affinity between the fragment crystallizable (Fc) region of aPDL1 and the Fc-III-4C peptide enabled aPDL1 and Fc-PLG-MMAE to self-assemble into aPDL1-PLG-MMAE after four hours of coincubation in PBS. As this nanomedicine can be quickly prepared for immediate use, the required antibodies can be stored separately from the Fc-PLG-MMAE portion for extended periods, which also facilitates transport. Moreover, aPDL1-PLG-MMAE demonstrated robust tumor recognition and targeting effects on MC38 colon cancer cells, resulting in potent therapeutic efficacy without significant toxicities.

Time Is a Critical Factor When Evaluating Oligonucleotide Therapeutics in Human Ether-a-Go-Go-Related Gene Assays

In accord with International Conference on Harmonization S7B guidelines, an in vitro human ether-a-go-go-related gene (hERG) assay is one component of an integrated risk assessment for delayed ventricular repolarization. Function of hERG could be affected by direct (acute) mechanisms, or by indirect (chronic) mechanisms. Some approved oligonucleotide therapeutics had submitted hERG data to regulatory agents, which were all collected with the same protocol used for small-molecule testing (incubation time <20 min; acute), however, oligonucleotides have unique mechanisms and time courses of action (indirect). To reframe the hERG testing strategy for silencing RNA (siRNA), an investigation was performed to assess the time course for siRNA-mediated inhibition of hERG function and gene expression. Commercially available siRNAs of hERG were evaluated in a stable hERG-expressed cell line by whole-cell voltage clamp using automated electrophysiology and polymerase chain reaction. In the acute hERG study, no effects were observed after treatment with 100 nM siRNA for 20 min. The chronic effects of 100 nM siRNAs on hERG function were evaluated and recorded over 8-48 h following transfection. At 8 h there was no significant effect, whereas 77% reduction was observed at 48 h. Measurement of hERG mRNA levels demonstrated a 79% and 93% decrease of hERG mRNA at 8 and 48 h, respectively, consistent with inhibition of hERG transcription. The results indicate that an anti-hERG siRNA requires a long exposure time (48 h) in the hERG assay to produce a maximal reduction in hERG current; short exposures (20 min-8 h) had no effect. These findings imply that off-target profiling of novel oligonucleotides could benefit from using hERG protocol with long incubation times to de-risk potential off-target (indirect) effects on the hERG channel. This hERG assay modification may be important to consider if the findings are used to support an integrated nonclinical-clinical risk assessment for QTc (the duration of the QT interval adjusted for heart rate) prolongation.

Future directions in cancer immunotherapy with monoclonal antibodies

Introduction: Cancer immunotherapy with monoclonal antibodies (mAbs) has become a therapy with great potential nowadays. It is based on the affinity of antibodies to bind to specific molecules, thus inhibiting the growth and spread of cancer. There is a wide variety of mAbs with differentiated mechanisms and enormous clinical benefits. However, different immunotherapeutic alternatives have emerged due to their limitations, such as the long duration of organ toxicity and the inability to penetrate intracellularly. This mini-review will discuss the emerging alternatives of cancer immunotherapies based on mAbs.

Bispecific antibodies (BsAbs): Antibodies designed to bind to two epitopes of an antigen.

Antibody fragments: Fragments of the Fab region generated from the variable region of IgG and IgM and a scFv.

Antibody-drug conjugates (ADCs): Administration of mAbs and a toxin of high specificity for a tumour target.

Nanobodies (or nanocomponents): Small fragments of antibody heavy chain.

Intrabodies (or intracellular antibodies): Antibodies that are expressed intracellularly and synthesised inside cells by retroviral delivery systems.

Stereospecific and catalytic mAbs: Antibodies that recognise the 3D configurations of target molecules.

Combination immunotherapies: Therapies that combine cytokines with tumour-targeted mAbs.

Small molecule immunotherapeutics: Small molecule drugs that can stimulate intracellular pathways primarily involved in immune cell checkpoints and bind to mAb-like targets.

Conclusion: These new varieties of immunotherapy present significant advantages, but future research should continue to improve their efficacy and safety and identify new biomarkers.

Graphical abstract:

Availability and Affordability of Therapeutic Monoclonal Antibodies After the New Medical Reform in Hubei Province, China

OBJECTIVE

In 2017, China launched a new round of medical reform (NMR) to address the inaccessibility of high-priced drugs for patients with serious diseases. This study explored the impact of the NMR on the accessibility and affordability of high-priced monoclonal antibodies (mAbs), and the effective promotion policies after the NMR.

METHODS

We used a standard method developed by the World Health Organization to conduct two surveys on the availability of mAbs and their prices before and after the NMR in the public hospitals in Hubei province, China. By interviewing hospital pharmacy experts, we identified the potential value of the current NMR in improving the access to therapeutic mAbs.

RESULTS

The average availability of 13 mAbs increased by 8.1% in the surveyed hospitals of Hubei province after the NMR. The median unit price of 10 mAbs dropped by 34.3%. The average affordability of a treatment cycle of 10 mAbs dropped from 680 days to 298 days of the disposable daily income for a middle-income resident (56.2% reduction). The drug price negotiation of medical insurance inclusion and the promotion of consistent evaluation of generic and original drugs could effectively promote the accessibility of mAbs. However, the zero markup of drug pricing and the limit on the proportion of drug revenues in public hospitals showed certain negative effects on the availability of mAbs.

CONCLUSION

Not all current NMR policies play a positive role in promoting the accessibility of mAbs. To further improve the accessibility of mAbs in the future in China, it is therefore critical to increase the investment in independent research and development of high-quality mAbs, establish localized guidelines for the rational use of mAbs in clinical practice, and have a cost-sharing mechanism for high-priced drugs with multiple stakeholders.

A simple nanobody-based competitive ELISA to detect antibodies against African swine fever virus

African swine fever virus (ASFV) infection is a big threat to the global pig industry. Because there is no effective vaccine, rapid, low-cost, and simple diagnosis methods are necessary to detect the ASFV infection in pig herds. Nanobodies, with advantages of small molecular weight and easy genetic engineering, have been universally used as reagents for developing diagnostic kits. In this study, the recombinant ASFV-p30 was expressed and served as an antigen to immunize the Bactrian camel. Then, seven nanobodies against ASFV-p30 were screened using phage display technique. Subsequently, the seven nanobodies fused horseradish peroxidase (nanobody-HRP) were secretory expressed and one fusion protein ASFV-p30-Nb75-HRP was selected with the highest sensitivity in blocking ELISA. Using the ASFV-p30-Nb75-HRP fusion protein as a probe, a competitive ELISA (cELISA) was developed for detecting anti-ASFV antibodies in pig sera. The cut-off value of cELISA was determined to be 22.7% by testing 360 negative pig sera. The detection limit of the cELISA for positive pig sera was 1:320, and there was no cross-reaction with anti-other swine virus antibodies. The comparative assay showed that the agreement of the cELISA with a commercial ELISA kit was 100%. More importantly, the developed cELISA showed low cost and easy production as a commercial kit candidate. Collectively, a simple nanobody-based cELISA for detecting antibodies against ASFV is developed and it provides a new method for monitoring ASFV infection in the pig herds.

The mosaic puzzle of the therapeutic monoclonal antibodies and antibody fragments - A modular transition from full-length immunoglobulins to antibody mimetics

The use of monoclonal antibodies represents an important and efficient diagnostic and therapeutic tool in disease management and modern science but remains limited by several factors including the uneven distribution in diseased tissues as well as undesired activation of side immune reactions. Major scientific advancements including Recombinant DNA Technology, Hybridoma Technology, and Polymerase Chain Reaction have considerably impacted the use of monoclonal antibodies providing technical and effective solutions to overcome the shortcomings encountered with conventional antibodies. Initially, the introduction of antibody fragments allowed a more uniform and deeper penetration of the targeted tissue and reduced unwanted activation of Fc-mediated immune reactions. On another level, the immunogenicity of murine-derived antibodies was overcome by humanizing their encoding genes with specific sequences of human origin andtransgenic mice able to synthesize fully human antibodies were successfully created. Moreover, the advancement of genetic engineering techniques supported by the modular structure of antibody coding genes paved the way for the development of a new generation of antibody fragments with a wide spectrum of monospecific and bispecific agents. These later could be monovalent, bivalent, or multivalent, and either expressed as a single chain, assembled in multimeric forms or stringed in tandem. This has conferred improved affinity, stability, and solubility to antibody targetting. Lately, a new array of monoclonal antibody fragments was introduced with the engineering of nanobody and antibody mimetics as non-immunoglobulin-derived fragments with promising diagnostic and therapeutic applications. In this review, we decipher the molecular basis of monoclonal antibody engineering with a detailed screening of the antibody derivatives that provides new perspectives to expand the use of monoclonal fragments into previously unexplored fields.

Separating clinical antibodies from repertoire antibodies, a path to in silico developability assessment

Approaches for antibody discovery have seen substantial improvement and success in recent years. Yet, advancing antibodies into the clinic remains difficult because therapeutic developability concerns are challenging to predict. We developed a computational model to simplify antibody developability assessment and enable accelerated early-stage screening. To this end, we quantified the ability of hundreds of sequence- and structure-based descriptors to differentiate clinical antibodies that have undergone rigorous screening and characterization for drug-like properties from antibodies in the human repertoire that are not natively paired. This analysis identified 144 descriptors capable of distinguishing clinical from repertoire antibodies. Five descriptors were selected and combined based on performance and orthogonality into a single model referred to as the Therapeutic Antibody Developability Analysis (TA-DA). On a hold-out test set, this tool separated clinical antibodies from repertoire antibodies with an AUC = 0.8, demonstrating the ability to identify developability attributes unique to clinical antibodies. Based on our results, the TA-DA score may serve as an approach for selecting lead antibodies for further development.

Abbreviations: Affinity-Capture Self-Interaction Nanoparticle Spectroscopy (AC-SINS), Area Under the Curve (AUC), Complementary-Determining Region (CDR), Clinical-Stage Therapeutics (CST), Framework (FR), Monoclonal Antibodies (mAbs), Observed Antibody Space (OAS), Receiver Operating Characteristic (ROC), Size-Exclusion Chromatography (SEC), Structural Aggregation Propensity (SAP), Therapeutic Antibody Developability Analysis (TA-DA), Therapeutic Antibody Profiler (TAP), Therapeutic Structural Antibody Database (Thera-SAbDab), Variable Heavy (VH), Variable Light (VL).

Therapeutic Antibodies: An Overview

Polyclonal immunoglobulin (Ig) preparations have been used for several decades for treatment of primary and secondary immunodeficiencies and for treatment of some infections and intoxications. This has demonstrated the importance of Igs, also called antibodies (Abs) for prevention and elimination of infections. Moreover, elucidation of the structure and functions of Abs has suggested that they might be useful for targeted treatment of several diseases, including cancers and autoimmune diseases. The development of technologies for production of specific monoclonal Abs (MAbs) in large amounts has led to the production of highly effective therapeutic antibodies (TAbs), a collective term for MAbs (MAbs) with demonstrated clinical efficacy in one or more diseases. The number of approved TAbs is currently around hundred, and an even larger number is under development, including several engineered and modified Ab formats. The use of TAbs has provided new treatment options for many severe diseases, but prediction of clinical effect is difficult, and many patients eventually lose effect, possibly due to development of Abs to the TAbs or to other reasons. The therapeutic efficacy of TAbs can be ascribed to one or more effects, including binding and neutralization of targets, direct cytotoxicity, Ab-dependent complement-dependent cytotoxicity, Ab-dependent cellular cytotoxicity or others. The therapeutic options for TAbs have been expanded by development of several new formats of TAbs, including bispecific Abs, single domain Abs, TAb-drug conjugates, and the use of TAbs for targeted activation of immune cells. Most promisingly, current research and development can be expected to increase the number of clinical conditions, which may benefit from TAbs.

Activation of Innate Immunity by Therapeutic Nucleic Acids

Nucleic acid-based therapeutics have gained increased attention during recent decades because of their wide range of application prospects. Immunostimulatory nucleic acids represent a promising class of potential drugs for the treatment of tumoral and viral diseases due to their low toxicity and stimulation of the body’s own innate immunity by acting on the natural mechanisms of its activation. The repertoire of nucleic acids that directly interact with the components of the immune system is expanding with the improvement of both analytical methods and methods for the synthesis of nucleic acids and their derivatives. Despite the obvious progress in this area, the problem of delivering therapeutic acids to target cells as well as the unresolved issue of achieving a specific therapeutic effect based on activating the mechanism of interferon and anti-inflammatory cytokine synthesis. Minimizing the undesirable effects of excessive secretion of inflammatory cytokines remains an unsolved task. This review examines recent data on the types of immunostimulatory nucleic acids, the receptors interacting with them, and the mechanisms of immunity activation under the action of these molecules. Finally, data on immunostimulatory nucleic acids in ongoing and completed clinical trials will be summarized.

Nanovesicles released by OKT3 hybridoma express fully active antibodies

Recent findings have shown that nanovesicles preparations from either primary immune cells culture supernatants or plasma contain immunoglobulins, suggesting that a natural way of antibody production may be through exosome release. To verify this hypothesis, we used the OKT3 hybridoma clone, which produces a murine IgG2a monoclonal antibody used to reduce rejection in patients undergoing organ transplantation. We showed exosome-associated immunoglobulins in hybridoma supernatants, by Western blot, nanoscale flow cytometry and immunocapture-based ELISA. The OKT3-exo was also being able to trigger cytokines production in both CD4 and CD8 T cells. These results show that nanovesicles contain immunoglobulin and could be used for immunotherapy. These data could lead to a new approach to improve the effectiveness of therapeutic antibodies by exploiting their natural property to be expressed on nanovesicle membrane, that probably render them more stable and as a consequence more capable to interact with their specific ligand in the best way.

Inhalation monoclonal antibody therapy: a new way to treat and manage respiratory infections

The route of administration of a therapeutic agent has a substantial impact on its success. Therapeutic antibodies are usually administered systemically, either directly by intravenous route, or indirectly by intramuscular or subcutaneous injection. However, treatment of diseases contained within a specific tissue necessitates a better alternate route of administration for targeting localised infections. Inhalation is a promising non-invasive strategy for antibody delivery to treat respiratory maladies because it provides higher concentrations of antibody in the respiratory airways overcoming the constraints of entry through systemic circulation and uncertainity in the amount reaching the target tissue. The nasal drug delivery route is one of the extensively researched modes of administration, and nasal sprays for molecular drugs are deemed successful and are presently commercially marketed. This review highlights the current state and future prospects of inhaled therapies, with an emphasis on the use of monoclonal antibodies for the treatment of respiratory infections, as well as an overview of their importance, practical challenges, and clinical trial outcomes.Key points• Immunologic strategies for preventing mucosal transmission of respiratory pathogens.• Mucosal-mediated immunoprophylaxis could play a major role in COVID-19 prevention.• Applications of monoclonal antibodies in passive immunisation.

Cancer immunotherapy: A comprehensive appraisal of its modes of application

Conventional cancer treatments such as chemotherapy and radiation therapy have reached their therapeutic potential, leaving a gap for developing more effective cancer therapeutics. Cancer cells evade the immune system using various mechanisms of immune tolerance, underlying the potential impact of immunotherapy in the treatment of cancer. Immunotherapy includes several approaches such as activating the immune system in a cytokine-dependent manner, manipulating the feedback mechanisms involved in the immune response, enhancing the immune response via lymphocyte expansion and using cancer vaccines to elicit long-lasting, robust responses. These techniques can be used as monotherapies or combination therapies. The present review describes the immune-based mechanisms involved in tumor cell proliferation and maintenance and the rationale underlying various treatment methods. In addition, the present review provides insight into the potential of immunotherapy used alone or in combination with various types of therapeutics.

Characterisation of a highly potent and near pan-neutralising anti-HIV monoclonal antibody expressed in tobacco plants

BACKGROUND

HIV remains one of the most important health issues worldwide, with almost 40 million people living with HIV. Although patients develop antibodies against the virus, its high mutation rate allows evasion of immune responses. Some patients, however, produce antibodies that are able to bind to, and neutralise different strains of HIV. One such 'broadly neutralising' antibody is 'N6'. Identified in 2016, N6 can neutralise 98% of HIV-1 isolates with a median IC50 of 0.066 µg/mL. This neutralisation breadth makes N6 a very promising therapeutic candidate.

RESULTS

N6 was expressed in a glycoengineered line of N. benthamiana plants (pN6) and compared to the mammalian cell-expressed equivalent (mN6). Expression at 49 mg/kg (fresh leaf tissue) was achieved in plants, although extraction and purification are more challenging than for most plant-expressed antibodies. N-glycoanalysis demonstrated the absence of xylosylation and a reduction in α(1,3)-fucosylation that are typically found in plant glycoproteins. The N6 light chain contains a potential N-glycosylation site, which was modified and displayed more α(1,3)-fucose than the heavy chain. The binding kinetics of pN6 and mN6, measured by surface plasmon resonance, were similar for HIV gp120. pN6 had a tenfold higher affinity for FcγRIIIa, which was reflected in an antibody-dependent cellular cytotoxicity assay, where pN6 induced a more potent response from effector cells than that of mN6. pN6 demonstrated the same potency and breadth of neutralisation as mN6, against a panel of HIV strains.

CONCLUSIONS

The successful expression of N6 in tobacco supports the prospect of developing a low-cost, low-tech production platform for a monoclonal antibody cocktail to control HIV in low-to middle income countries.

Advancing HIV Broadly Neutralizing Antibodies: From Discovery to the Clinic

Despite substantial progress in confronting the global HIV-1 epidemic since its inception in the 1980s, better approaches for both treatment and prevention will be necessary to end the epidemic and remain a top public health priority. Antiretroviral therapy (ART) has been effective in extending lives, but at a cost of lifelong adherence to treatment. Broadly neutralizing antibodies (bNAbs) are directed to conserved regions of the HIV-1 envelope glycoprotein trimer (Env) and can block infection if present at the time of viral exposure. The therapeutic application of bNAbs holds great promise, and progress is being made toward their development for widespread clinical use. Compared to the current standard of care of small molecule-based ART, bNAbs offer: (1) reduced toxicity; (2) the advantages of extended half-lives that would bypass daily dosing requirements; and (3) the potential to incorporate a wider immune response through Fc signaling. Recent advances in discovery technology can enable system-wide mining of the immunoglobulin repertoire and will continue to accelerate isolation of next generation potent bNAbs. Passive transfer studies in pre-clinical models and clinical trials have demonstrated the utility of bNAbs in blocking or limiting transmission and achieving viral suppression. These studies have helped to define the window of opportunity for optimal intervention to achieve viral clearance, either using bNAbs alone or in combination with ART. None of these advances with bNAbs would be possible without technological advancements and expanding the cohorts of donor participation. Together these elements fueled the remarkable growth in bNAb development. Here, we review the development of bNAbs as therapies for HIV-1, exploring advances in discovery, insights from animal models and early clinical trials, and innovations to optimize their clinical potential through efforts to extend half-life, maximize the contribution of Fc effector functions, preclude escape through multiepitope targeting, and the potential for sustained delivery.

Therapeutic Antibodies Targeting Potassium Ion Channels

Monoclonal antibodies combine specificity and high affinity binding with excellent pharmacokinetic properties and are rapidly being developed for a wide range of drug targets including clinically important potassium ion channels. Nonetheless, while therapeutic antibodies come with great promise, K⁺ channels represent particularly difficult targets for biologics development for a variety of reasons that include their dynamic structures and relatively small extracellular loops, their high degree of sequence conservation (leading to immune tolerance), and their generally low-level expression in vivo. The process is made all the more difficult when large numbers of antibody candidates must be screened for a given target, or when lead candidates fail to cross-react with orthologous channels in animal disease models due to their highly selective binding properties. While the number of antibodies targeting potassium channels in preclinical or clinical development is still modest, significant advances in the areas of protein expression and antibody screening are converging to open the field to an avalanche of new drugs. Here, the opportunities and constraints associated with the discovery of antibodies against K⁺ channels are discussed, with an emphasis on novel technologies that are opening the field to exciting new possibilities for biologics development.

Technological Advancements in Monoclonal Antibodies

Biopharmaceuticals are innovative solutions that have revolutionized the treatment of important chronic diseases and malignancies. The approval of biosimilar products has become a complex and balanced process, and there are versions of drugs with established biosimilarity that can offer a more accessible treatment option to patients. The objective of this work was to identify the advancement of these technologies by means of patent and article analysis based on technological and scientific prospection. In patent document recovery, Derwent Innovation Index (DWPI) and PatentInspiration databases were used. The research was based on the search of the selected terms in the title, summary, and claims of the documents through a search strategy containing IPC code and keywords. In articles recovery, the Web of Science tool was used in the search of scientific publications dated from the last 5 years. The search resulted in a total of 2295 individual patent documents and 467 families using DWPI database, 769 individual patents and 205 families using PatentInspiration, and 2602 articles using Web of Science database. Additionally, this work describes the number of organizations that contribute to this area, where they are, how much development they have undergone, and the inventors/authors involved. Based on the number of publications registered, there is an important prominence for scientific research in mAbs. In terms of innovation, it is expected that several therapeutic drugs are already under regulatory review, which will allow drugs to be approved over the next few years and will thus generate a continuous flow of new products based on immunotherapies, mAbs, and biosimilar drugs. These drugs have become essential weapons for the treatment of significant diseases, and the increasing trend in the number of related scientific and technological publications contributes to making these therapies available to the greatest number of people.

Discovery-stage identification of drug-like antibodies using emerging experimental and computational methods

There is intense and widespread interest in developing monoclonal antibodies as therapeutic agents to treat diverse human disorders. During early-stage antibody discovery, hundreds to thousands of lead candidates are identified, and those that lack optimal physical and chemical properties must be deselected as early as possible to avoid problems later in drug development. It is particularly challenging to characterize such properties for large numbers of candidates with the low antibody quantities, concentrations, and purities that are available at the discovery stage, and to predict concentrated antibody properties (e.g., solubility, viscosity) required for efficient formulation, delivery, and efficacy. Here we review key recent advances in developing and implementing high-throughput methods for identifying antibodies with desirable in vitro and in vivo properties, including favorable antibody stability, specificity, solubility, pharmacokinetics, and immunogenicity profiles, that together encompass overall drug developability. In particular, we highlight impressive recent progress in developing computational methods for improving rational antibody design and prediction of drug-like behaviors that hold great promise for reducing the amount of required experimentation. We also discuss outstanding challenges that will need to be addressed in the future to fully realize the great potential of using such analysis for minimizing development times and improving the success rate of antibody candidates in the clinic.

Combining the advantages of prokaryotic expression and T7 phage display systems to obtain antigens for antibody preparation

The gene encoding the phage major capsid protein 10A was cloned into the prokaryotic expression vector pET24a, and a 6XHis-tag was fused to the 3'-end of the 10A gene to verify complete expression. The recombinant plasmid was transformed into Escherichia coli (E. coli) BL21 (DE3) cells, and 10A expression was induced by IPTG. SDS-PAGE and Western blot were used to confirm the target protein expression. The T7Select10-3b vector was added to the cultured bacteria expressing 10A at a multiplicity of infection (MOI) ranging from 0.01 to 0.1, and complete lysis of the bacteria was monitored by absorbance changes in the medium. The recombinant phage (reP) was harvested by PEG/NaCl sedimentation and resuspended in PBS. ELISA was performed to verify the presence of the 6XHis-tag on the surface of reP. The 10A-fusion expression vectors (pET10A-flag, pET10A-egfp, and pET10A-pct) were constructed, and fusion proteins were expressed and detected by the same method. The corresponding rePs (reP-Flag, reP-EGFP, and reP-PCT) were prepared by T7Select10-3b infection. After the expression of the peptides/proteins on the reP surfaces was confirmed, reP-Flag and reP-PCT were used to immunize mice to prepare anti-Flag and anti-PCT antibodies. The results showed that rePs prepared using the 10A-fusion vector and T7Select10-3b can be used as antigens to immunize mice and prepare antibodies. This method may be able to meet the rapid antigen preparation requirements for antibody production. Notably, the recombinant phage (reP) described in this study was obtained by the sedimentation method from T7Select10-3b-infected E. coli BL21 (DE3) cells carrying the major capsid protein 10A expression vector or 10A-fusion protein vector.

PK, PD, and interactions: the new scenario with JAK inhibitors and S1P receptor modulators, two classes of small molecule drugs, in IBD

INTRODUCTION

Inflammatory bowel diseases (IBDs) are immune-mediated chronic inflammatory disorders of the gastrointestinal tract whose pathogenesis is not yet fully understood. Despite the advent of biological agents, there are still unmet needs for IBD patients, due to suboptimal rate of sustained remission achieved. Small molecule drugs (SMDs), the next generation of selective drugs in IBD, show promising results in ongoing trials.

AREAS COVERED

We describe the pharmacodynamics and pharmacokinetic features of novel SMDs and their main differences with biologic agents.

EXPERT OPINION

Small molecule drugs are a promising class of drugs for the treatment of ulcerative colitis and Crohn's disease with good results in inducing and maintaining remission. Hence, over the next few years physicians will have numerous options of small molecule drugs for the treatment of patients with IBD. This group of drugs are potentially easier to use over biological agents due to pharmacokinetic features such as oral administration, short half-life, high volume of distribution, and lack of immunogenicity. On the other hand, drug-drug interactions can happen with small-molecule drugs, principally due to competitive metabolic and clearance mechanisms.

Vaccination in patients under monoclonal antibody treatment: an updated comprehensive review

INTRODUCTION

Monoclonal antibodies (mAbs) have become an increasing source of biological treatments. Clinicians should make an effort to update their knowledge on mechanisms of action, indications, and adverse events of these novel therapies. Most of them have immunosuppressive effects and, therefore, vaccination is indicated.

AREAS COVERED

vaccination of patients under mAbs therapies.

EXPERT OPINION

Recommendations on vaccination are still based on expert recommendations and have not been updated in recent years. Specific recommendations for each mAb have not been addressed in the current literature. The aim of this comprehensive review was to collect all the therapeutic mAbs approved up to 1 January 2020 and, based on previous recommendations and the pharmaceutical characteristics of each drug, to propose an updated guide with recommendations on vaccination. Influenza, sequential pneumococcal and Hepatitis B vaccination in patients with negative serology were the only consistent recommendations. Hepatitis A vaccination was proposed for mAbs with special hepatotoxic characteristics. Other vaccines are reviewed and discussed. Several non-immunosuppressive mAbs were detected and, therefore, vaccinations not recommended. We hope that this review can serve as a starting point for compiling updated vaccination recommendations and collecting all the therapeutic mAbs approved up to 2020.