Fig. 1. Production and functional screening of 105 unique antibody combinations on a DNA chassis.
a, Schematic of a multispecific antibody chassis variant library created from a set of antibody–DNA conjugates. The symbols indicate the antibody, and the colour indicates the engaged cell type. Antibodies are covalently tagged with DNA handles with the sequences A, B, C or D, depending on the library, and the sequences are complementary to DNA handles on the chassis (centre). The chassis carries four DNA handles. Antibody chassis variants are produced by mixing the respective antibodies from the libraries with the DNA chassis. Variants are named by their antibody combination (the centre bottom shows an example combination). Two reference-free class averages calculated from single-particle TEM micrographs. Scale bar, 20 nm. The top average shows the platform without antibodies and the bottom average image shows the platform with four IgG antibodies, indicated by the orange and blue arrow heads pointing to the blurred additional signal in the average image. b, Montage of laser-scanned images of agarose gels on which 105 variants were electrophoresed that were incubated with different antibody combinations (as indicated by the symbols). The first and last lanes show a reference 5 MDa DNA origami object. c,d, T-cell activation was measured by using NFAT-luciferase Jurkat cell line in co-cultures with human ALL cell line NALM-6 in the presence of the indicated combinations (c,d). Relative T-cell activation (normalized to variants without target cell antibodies) of different variants for 100 pM and 1,000 pM DNA chassis concentrations. The icons in orange and blue indicate the respective antibodies used in the combination. e, Relative T-cell activation of the variants sorted for maximum activation according to the values in c and d at 100 pM.