Eukaryotic ribosome display with in situ DNA recovery

Eukaryotic ribosome display for antibody discovery: A review

Monoclonal antibody biologics have significantly transformed the therapeutic landscape within the biopharmaceutical industry, partly due to the utilisation of discovery technologies such as the hybridoma method and phage display. While these established platforms have streamlined the development process to date, their reliance on cell transformation for antibody identification faces limitations related to library diversification and the constraints of host cell physiology. Cell-free systems like ribosome display offer a complementary approach, enabling antibody selection in a completely in vitro setting while harnessing enriched cellular molecular machinery. This review aims to provide an overview of the fundamental principles underlying the ribosome display method and its potential for advancing antibody discovery and development.

Single-Dose P2 X4R Single-Chain Fragment Variable Antibody Permanently Reverses Chronic Pain in Male Mice

Non-opioid single-chain variable fragment (scFv) small antibodies were generated as pain-reducing block of P2X4R receptor (P2X4R). A panel of scFvs targeting an extracellular peptide sequence of P2X4R was generated followed by cell-free ribosome display for recombinant antibody selection. After three rounds of bio-panning, a panel of recombinant antibodies was isolated and characterized by ELISA, cross-reactivity analysis, and immunoblotting/immunostaining. Generated scFv antibodies feature binding activity similar to monoclonal antibodies but with stronger affinity and increased tissue penetrability due to their ~30% smaller size. Two anti-P2X4R scFv clones (95, 12) with high specificity and affinity binding were selected for in vivo testing in male and female mice with trigeminal nerve chronic neuropathic pain (FRICT-ION model) persisting for several months in untreated BALBc mice. A single dose of P2X4R scFv (4 mg/kg, i.p.) successfully, completely, and permanently reversed chronic neuropathic pain-like measures in male mice only, providing retention of baseline behaviors indefinitely. Untreated mice retained hypersensitivity, and developed anxiety- and depression-like behaviors within 5 weeks. In vitro P2X4R scFv 95 treatment significantly increased the rheobase of larger-diameter (>25 µm) trigeminal ganglia (TG) neurons from FRICT-ION mice compared to controls. The data support use of engineered scFv antibodies as non-opioid biotherapeutic interventions for chronic pain.

Ribosome Display Technology: Applications in Disease Diagnosis and Control

Antibody ribosome display remains one of the most successful in vitro selection technologies for antibodies fifteen years after it was developed. The unique possibility of direct generation of whole proteins, particularly single-chain antibody fragments (scFvs), has facilitated the establishment of this technology as one of the foremost antibody production methods. Ribosome display has become a vital tool for efficient and low-cost production of antibodies for diagnostics due to its advantageous ability to screen large libraries and generate binders of high affinity. The remarkable flexibility of this method enables its applicability to various platforms. This review focuses on the applications of ribosome display technology in biomedical and agricultural fields in the generation of recombinant scFvs for disease diagnostics and control.

HybriFree: a robust and rapid method for the development of monoclonal antibodies from different host species

BACKGROUND

The production of recombinant monoclonal antibodies in mammalian cell culture is of high priority in research and medical fields. A critical step in this process is the isolation of the antigen-binding domain sequences of antibodies possessing the desired properties. Many different techniques have been described to achieve this goal, but all have shortcomings; most techniques have problems with robustness, are time-consuming and costly, or have complications in the transfer from isolation to production phase. Here, we report a novel HybriFree technology for the development of monoclonal antibodies from different species that is robust, rapid, inexpensive and flexible and can be used for the subsequent production of antibodies in mammalian cell factories.

RESULTS

HybriFree technology is illustrated herein via detailed examples of isolating mouse, rabbit and chicken monoclonal antibody sequences from immunized animals. Starting from crude spleen samples, antigen capturing of specific B-cells is performed initially. cDNA of antibody variable domains is amplified from the captured cells and used a source material for simple and rapid restriction/ligation free cloning of expression vector library in order to produce scFv-Fc or intact IgG antibodies. The vectors can be directly used for screening purposes as well as for the subsequent production of the developed monoclonal antibodies in mammalian cell culture. The antibodies isolated by the method have been shown to be functional in different immunoassays, including ELISA, immunofluorescence and Western blot. In addition, we demonstrate that by using a modified method including a negative selection step, we can isolate specific antibodies targeting the desired epitope and eliminate antibodies directed to undesired off-targets.

CONCLUSIONS

HybriFree can be used for the reliable development of monoclonal antibodies and their subsequent production in mammalian cells. This simple protocol requires neither the culturing of B-cells nor single-cell manipulations, and only standard molecular biology laboratory equipment is needed. In principle, the method is applicable to any species for which antibody cDNA sequence information is available.

Eukaryotic ribosome display selection using rabbit reticulocyte lysate

Ribosome display is a powerful in vitro technology for the selection and directed evolution of proteins. Cell-free translation is central to the ribosome display process and is performed in such a way that the ribosome provides the link between genotype and phenotype that allows genes encoding proteins with desired properties to be identified by selection. Prokaryotic cell-free translation reagents, based initially on E. coli cell extracts and more recently containing purified and recombinant factors, have dominated the ribosome display literature. Eukaryotic cell extracts are also suitable for ribosome display; however, protocols for prokaryotic ribosome display are not directly transferable to the use of eukaryotic cell extracts. This chapter describes an optimised methodology for the use of rabbit reticulocyte lysate for ribosome display selections.