From Monoclonal to Multifunctional: The Evolving Landscape of Engineered Antibodies

Abstract

Antibodies play a crucial role in the adaptive immune system by accurately identifying and neutralizing pathogens, toxins, and irregular cells. Their structural configuration comprising heavy and light chains, antigen-binding fragments (Fab), and crystallizable fragments (Fc) is critical to their specificity and functional flexibility, serving both as immune components and therapeutic agents. Over recent decades, breakthroughs in molecular biology and protein engineering have revolutionized antibody technology, transitioning from conventional hybridomaderived monoclonal antibodies to recombinant and fully human antibodies. Phage display has pioneered the largescale discovery of antibodies, while yeast and mammalian display systems have introduced eukaryotic folding and post-translational modifications, facilitating the selection of high-quality therapeutic candidates. Site-directed mutagenesis has emerged as a fundamental technique in antibody engineering, enabling targeted optimization of complementarity-determining regions to improve affinity, specificity, and stability. Concurrently, ribosome and mRNA display technologies have allowed for in vitro screening of extremely large libraries, bypassing host transformation hurdles and speeding up the evolution of high-performance antibody variants. Collectively, these integrated strategies create a robust pipeline for rational antibody design, affinity maturation, and the development of next-generation biologics. This review brings together historical milestones, technological advancements, and state-of-the-art engineering techniques, offering a thorough overview of how antibody engineering continuously influences biomedical research, diagnostics, and the discovery of therapeutic drugs.