Creative Biolabs is a leading provider of phage display library construction services. In the process of antibody generation, biopanning is a critical step which directly affects the quality of the antibodies selected. Our scientists are able to employ a serial of selection methods to ensure the generation of high-quality antibodies. Cell-based screening is a method in particular for cell surface antigen selection. Creative Biolabs has developed an optimized procedure which facilitates the selection of antibody with high specificity and affinity.
In general, solid phase screening is the most common screening methods, which the antigens are attached to plates or other solid phases and then presented with the libraries. While, some obstacles may prevent the discovery of effective antibodies during this approach. For example, the antigens cannot maintain the native conformation since they are immobilized on the solid surface. Thus some antibodies selected from solid phase may not recognize the native antigen with high specificity and affinity. In addition, for some cell surface antigens that are hardly expressed as recombinant proteins, solid phase screening is likely to fail to isolate specific antibodies. In this case, cell-based screening can be a more reliable approach to be competent for such task.
Advantages of cell-based screening
The method of cell-based screening circumvents the disadvantages of solid phase selection by displaying the antigens in their native forms. The best application of this method is to select antibodies for cell surface receptors, such as G protein-coupled receptors (GPCR), ion channel-linked receptors and enzyme-linked receptors. In addition, it could be used to select antibodies for structure studies in co-crystallization. Furthermore, the cell-based selection could target the cell surface proteins that are overexpressed or modified by disease, which brings in the novel epitopes.
While using purified antigens could be very effective in selection, cell surface antigens are more complex therefore more challenging. Creative Biolabs has developed an advanced selection platform that ensures the high expression level of the targets. In addition, the incorporation of positive selection and depletion steps will further improve the affinity and the specificity of the selected binder.
Figure 1. Scheme for affinity selection of landscape phage ligands demonstrating the isolation of cell surface bound phage as well as cell-internalized phage. (Jayanna et al. 2008)
Creative Biolabs has long-term devoted to developing and optimizing the effectiveness and the efficiency of phage display library screening. With years of experience, our scientists have developed several biopanning methods which apply to different types of targets to boost our global customers’ research and project goals. Among them, the cell-based library screening is highly promising for the development of therapeutic or imaging agents. We are pleased to use our extensive experience and advanced platform to offer the best service and the most qualified products to satisfy each demand from our customers.