The baculovirus display technology--an evolving instrument for molecular screening and drug delivery.

High throughput screening is a core technology in drug discovery. During the past decade, several strategies have been developed to screen (poly)peptide libraries for diverse applications including disease diagnosis and profiling, imaging, as well as therapy. The recently established baculovirus display vector system (BDVS) represents a eukaryotic screening platform that combines the positive attributes of both cell and virus-based display approaches, allowing presentation of complex polypeptides on cellular and viral surfaces. Compared to microbial display systems, the BDVS has the advantage of correct protein folding and post-translational modifications similar to those in mammals, facilitating expression and analysis of proteins with therapeutic interest. The applicability of the system is further expanded by the availability of genetically engineered insect cell lines capable of performing e.g. mammalianized glycosylation in combination with high level of expression. In addition to insect cells, baculovirus can mediate delivery and expression of heterologous genes in a broad spectrum of primary and established mammalian cells. Currently, a variety of baculovirus-based assays aiming at routine high throughput identification of agents targeting cell surface receptors or studies on ligand-receptor interactions are under construction. Here, the advancements and future prospects of the baculovirus display technologies with emphasis on molecular screening and drug delivery applications using insect cell display, mammalian cell display, and virion display are described.