2 results about "Yeast display" patented technology

The invention discloses a high-affinity HER2 targeting polycyclic peptide molecule and a preparation method and application thereof.The preparation method comprises the steps that affinity optimization is conducted on initial HER2 targeting polycyclic peptides obtained through phage display library screening by combining a yeast display technology with an error-prone PCR directed evolution system, and a series of high-affinity disulfide bond-rich polycyclic peptides (DDMP) are obtained; the polycyclic peptide is coupled with a conjugate (DOTA or FITC) and a linker, so that a monovalent or divalent molecular probe can be constructed; the molecular probe has high specificity, high stability and good biocompatibility, can be used for accurate imaging and quantitative evaluation of HER2 positive cells / tumors and diagnosis and targeted therapy of HER2 signal path related diseases through radionuclide labeling or fluorescence labeling, and provides a novel tool and a transformation basis for early diagnosis and accurate treatment of HER2 positive solid tumors.

The application discloses a method for modifying pH sensitivity of an antibody based on yeast display. A degenerate codon VAM (coding H, E, D, K, N, Q) is used to construct a yeast display library for at least two region combinations in LCDR1, HCDR1 and HCDR3, and 1-2 mutations are introduced into each CDR region, taking the antibody to be modified as a template. The library is transformed into Saccharomyces cerevisiae EBY100 to induce expression, and fast dissociation clones are enriched through four rounds of flow sorting (including pH 7.4 binding, pH 6.0 non-binding and'saturated binding-acid dissociation-neutral re-binding' screening). The obtained antibody has a KD ratio at pH 5.8 to pH 7.4 of up to 674.46, an expression amount of up to 263.3 mg / L, excellent physicochemical properties, and can enhance the curative effect of antibody conjugated drugs and improve the therapeutic index.