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Through the discovery of monoclonal antibody (mAb) technology, profound successes in medical treatment against a wide range of diseases have been achieved. This has led antibodies to emerge as a new class of biodrugs. As the "rising star" in the pharmaceutical market, extensive research and development in antibody production has been carried out in various expression systems including bacteria, insects, plants, yeasts, and mammalian cell lines. The major benefit of eukaryotic expression systems is the ability to carry out posttranslational modifications of the antibody. Glycosylation of therapeutic antibodies is one of these important modifications, due to its influence on antibody structure, stability, serum half-life, and complement recruitment. In recent years, the protozoan parasite Leishmania tarentolae has been introduced as a new eukaryotic expression system. L. tarentolae is rich in glycoproteins with oligosaccharide structures that are very similar to humans. Therefore, it is touted as a potential alternative to mammalian expression systems for therapeutic antibody production. Here, we present a comparative review on the features of the L. tarentolae expression system with other expression platforms such as bacteria, insect cells, yeasts, transgenic plants, and mammalian cells with a focus on mAb production. [ABSTRACT FROM AUTHOR]

Ancylostoma species are parasitic nematodes that release a multitude of proteins to manipulate host immune responses to facilitate their survival. Among the released proteins, Ancylostoma-secreted protein 5 (ASP5) plays a pivotal role in mediating host-parasite interactions, making it a promising target for interventions against canine hookworm infections caused by Ancylostoma species. Antibody phage display, a widely used method for generating human monoclonal antibodies was employed in this study. A bacterial expression system was used to produce ASP5 for biopanning. A single-chain fragment variable (scFv) monoclonal antibody against ASP5 was generated from the naïve Human AntibodY LibrarY (HAYLY). The resulting scFv antibody was characterized to elucidate its antigen-binding properties. The identified monoclonal antibody showed good specificity and binding characteristics which highlighting its potential for diagnostic applications in combating hookworm infections., Competing Interests: Declaration of competing interest All authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)

Background/aim: To evaluate efficacy of the AIxURO system, a deep learning-based artificial intelligence (AI) tool, in enhancing the accuracy and reliability of urine cytology for diagnosing upper urinary tract cancers., Materials and Methods: One hundred and eighty-five cytology samples of upper urine tract were collected and categorized according to The Paris System for Reporting Urinary Cytology (TPS), yielding 168 negative for High-Grade Urothelial Carcinoma (NHGUC), 14 atypical urothelial cells (AUC), 2 suspicious for high-grade urothelial carcinoma (SHGUC), and 1 high-grade urothelial carcinoma (HGUC). The AIxURO system, trained on annotated cytology images, was employed to analyze these samples. Independent assessments by a cytotechnologist and a cytopathologist were conducted to validate the initial AIxURO assessment., Results: AIxURO identified discrepancies in 37 of the 185 cases, resulting in a 20% discrepancy rate. The cytotechnologist achieved an accuracy of 85% for NHGUC and 21.4% for AUC, whereas the cytopathologist attained accuracies of 95% for NHGUC and 85.7% for AUC. The cytotechnologist exhibited overcall rates of roughly 15% and undercall rates of greater than 50%, while the cytopathologist showed profoundly lower miscall rates from both undercall and overcall. AIxURO significantly enhanced diagnostic accuracy and consistency, particularly in complex cases involving atypical cells., Conclusion: AIxURO can improve the accuracy and reliability of cytology diagnosis for upper urine tract urothelial carcinomas by providing precise detection on atypical urothelial cells and reducing subjectivity in assessments. The integration of AIxURO into clinical practice can significantly ameliorate diagnostic outcomes, highlighting the synergistic potential of AI technology and human expertise in cytology., (Copyright © 2024, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Phage display antibody libraries have been successfully used as the essential tool to produce monoclonal antibodies against a plethora of targets ranging from diseases to native biologically important proteins as well as small molecules. It is well documented that diverse antibody genes are the major genetic source for the construction of a high-quality antibody library and selection of high-affinity antibodies. Naïve antibody libraries are derived using the IgM repertoire of healthy donors obtained from B-cells isolated from human peripheral blood mononuclear cell (PBMC). Single-chain fragment variable (scFv) is a routinely used format due to its smaller size and preference for phage display. The process involves the use of a two-step cloning method for library construction. The protocol also covers the biopanning process for target positive clone selection., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

The application of antibodies has transcended across many areas of work but mainly as a research tool, for diagnostic and for therapeutic applications. Antibodies are immunoproteins from vertebrates that have the unique property of specifically binding foreign molecules and distinguish target antigens. This property allows antibodies to effectively protect the host from infections. Apart from the hybridoma technology using transgenic animals, antibody phage display is commonly considered the gold standard technique for the isolation of human monoclonal antibodies. The concept of antibody phage display surrounds the ability to display antibody fragments on the surface of M13 bacteriophage particles with the corresponding gene packaged within the particle. A repetitive in vitro affinity based selection process permits the enrichment of target specific binders. This process of recombinant human monoclonal antibody generation also enables additional engineering for various applications. This makes phage display an indispensable technique for antibody development and engineering activities., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Phage display has been applied successfully for the rapid isolation of monoclonal antibodies against various targets including infectious diseases, autoantigens, cancer markers, and even small molecules. The main component in any phage display experiment is the availability of an antibody library to carry out the selection process of target-specific antibodies through an iterative process termed as biopanning. To generate human antibody libraries, the antibody repertoire can be obtained from human peripheral blood mononuclear cell (PBMC) or directly from cell-sorted B-cell populations. The choice of antibody isotype is dictated by the nature of the library. Naïve libraries would utilize IgM repertoires, whereas the IgG repertoire is commonly used for immune libraries. Antibody genes are amplified through polymerase chain reaction (PCR) and paired in a combinatorial fashion to expand the diversity of the cloned library repertoire. The protocol here describes the use of a two-step cloning method that can be applied for the construction of either a naïve or immune human antibody library in Fab format followed by the subsequent panning., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Phage display is a technique that allows the presentation of unique proteins on the surface of bacteriophages. The phage particles are usually screened via repetitive rounds of antigen-guided selection and phage amplification. The main advantage of this approach lies in the physical linkage between phenotype and genotype. This feature allows the isolation of single unique clones from a panning campaign consisting of a highly diverse population of clones. Due to the high-throughput nature of this technique, different approaches have been developed to assist phage display selections. One of which involves utilizing a streptavidin-coated solid-phase extraction (SPE) tip that is mounted to an electronically controlled motorized multichannel pipette. In this chapter, we will entail the procedures involved in the adaptation of a commercial SPE tip (MSIA™ streptavidin D.A.R.T's ® ) as the solid phase. This protocol is an updated version of a previous protocol with some minor refinements., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)