Selective Uptake of Cylindrical Poly(2-Oxazoline) Brush-AntiDEC205 Antibody-OVA Antigen Conjugates into DEC-Positive Dendritic Cells and Subsequent T-Cell Activation

To achieve specific cell targeting by various receptors for oligosaccharides or antibodies, a carrier must not be taken up by any of the very many different cells and needs functional groups prone to clean conjugation chemistry to derive well-defined structures with a high biological specificity. A polymeric nanocarrier is presented that consists of a cylindrical brush polymer with poly-2-oxazoline side chains carrying an azide functional group on each of the many side chain ends. After click conjugation of dye and an anti-DEC205 antibody to the periphery of the cylindrical brush polymer, antibody-mediated specific binding and uptake into DEC205(+)-positive mouse bone marrow-derived dendritic cells (BMDC) was observed, whereas binding and uptake by DEC205(-) negative BMDC and non-DC was essentially absent. Additional conjugation of an antigen peptide yielded a multifunctional polymer structure with a much stronger antigen-specific T-cell stimulatory capacity of pretreated BMDC than application of antigen or polymer-antigen conjugate.