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CN-122005857-A - Double-antibody modified vesicle STING agonist, preparation method and application

CN122005857ACN 122005857 ACN122005857 ACN 122005857ACN-122005857-A

Abstract

The application provides a double-antibody modified vesicle STING agonist, a preparation method and application thereof, and relates to the technical field of polymer nano-drugs. The double antibody modified vesicle STING agonist comprises a vesicle, a STING agonist and a double antibody, wherein the vesicle is formed by crosslinking and assembling a functionalized amphiphilic block polymer and an amphiphilic block polymer, the inner cavity of the vesicle is electronegative, the STING agonist is loaded in the inner cavity of the vesicle by electrostatic interaction, and the double antibody comprises an anti-HER 2 monoclonal antibody and an anti-PD 1 monoclonal antibody grafted on the surface of the vesicle. The double antibody modified vesicle STING agonist has good biological safety, and can enhance the killing effect of T cells on tumor cells, thereby killing the tumor cells.

Inventors

  • SUN HUANLI
  • CHEN LIN
  • ZHONG ZHIYUAN

Assignees

  • 苏州大学

Dates

Publication Date
20260512
Application Date
20260413

Claims (9)

  1. 1. A diabody modified vesicle STING agonist, characterized by comprising the following steps: The vesicle is formed by assembling and crosslinking a functionalized amphiphilic block polymer and an amphiphilic block polymer containing a negative electric chain segment, wherein the inner cavity of the vesicle presents electronegativity, the particle size of the vesicle is 20-35 nm, the functionalized amphiphilic block polymer is a functional group-a second hydrophilic chain segment-a second hydrophobic chain segment, and the functional group is N 3 -, mal-or NHS-; STING agonists are loaded into the lumen of the vesicles by electrostatic interactions; the double antibody comprises an anti-HER 2 monoclonal antibody and an anti-PD-1 monoclonal antibody which are respectively and covalently grafted on the surface of the vesicle, wherein the anti-HER 2 monoclonal antibody and the anti-PD-1 monoclonal antibody are both functional group modified antibodies, the functional group is dibenzocyclooctyne, the ratio of the anti-HER 2 monoclonal antibody to the anti-PD-1 monoclonal antibody grafted on the surface of the vesicle is 1 (0.33-3), the anti-HER 2 monoclonal antibody is used for targeting HER2 antigen on the surface of tumor cells, and the anti-PD-1 monoclonal antibody is used for targeting PD-1 antigen on the surface of T cells.
  2. 2. The diabody modified vesicle STING agonist of claim 1, The STING agonist is selected from diABZI, STING agonist-3, SR-717 or GNE-6468.
  3. 3. The diabody modified vesicle STING agonist of claim 2, The amphiphilic block polymer is a first hydrophilic chain segment-a first hydrophobic chain segment-Ac-KD z , wherein, The first hydrophilic chain segment is polyethylene glycol, the first hydrophobic chain segment is a random copolymer of trimethylene carbonate monomer and disulfide five-membered ring carbonate monomer, ac is acetyl, KD z is a negative chain segment, K is lysine, D is aspartic acid, and z represents a repeating unit.
  4. 4. The diabody-modified vesicle STING agonist according to claim 3, The second hydrophilic chain segment is polyethylene glycol, and the second hydrophobic chain segment is a random copolymer of trimethylene carbonate monomer and disulfide five-membered ring carbonate monomer.
  5. 5. The diabody-modified vesicle STING agonist according to claim 4, The quality of the STING agonist accounts for 1% -11.2% of the total quality of the vesicle and the STING agonist.
  6. 6. Use of a diabody modified vesicle STING agonist according to any one of claims 1-5 in anti-tumor immunotherapy.
  7. 7. A method of preparing a diabody modified vesicle STING agonist as claimed in any one of claims 1 to 5 comprising the steps of: Providing an amphiphilic block polymer and a functionalized amphiphilic block polymer; Preparing an organic solution containing the amphiphilic block polymer, the functionalized amphiphilic block polymer and an acidic buffer solution containing STING agonist, mixing the organic solution with the acidic buffer solution, and obtaining the vesicle STING agonist through dialysis and ultrafiltration; Preparing the functional group modified anti-HER 2 monoclonal antibody and the functional group modified anti-PD-1 monoclonal antibody; Mixing the vesicle STING agonist, the anti-HER 2 monoclonal antibody and the anti-PD-1 monoclonal antibody according to a preset molar ratio, so that the anti-HER 2 monoclonal antibody and the anti-PD-1 monoclonal antibody are both covalently grafted on the surface of the vesicle STING agonist, and the diabody modified vesicle STING agonist is prepared.
  8. 8. The method according to claim 7, wherein in the step of preparing the diabody modified vesicle STING agonist, the anti-HER 2 mab and the anti-PD-1 mab are mixed and treated according to a predetermined molar ratio such that the anti-HER 2 mab and the anti-PD-1 mab are both covalently grafted to the surface of the vesicle STING agonist, the predetermined molar ratio of the functional group of the vesicle STING agonist, the anti-HER 2 mab and the anti-PD-1 mab is any one of 1 (0.17-0.5): 0.17-0.5.
  9. 9. The method according to claim 7, wherein in the step of preparing an organic solution containing the amphiphilic block polymer, the functionalized amphiphilic block polymer and an acidic buffer solution containing STING agonist, mixing the organic solution with the acidic buffer solution and obtaining a vesicle STING agonist by dialysis and ultrafiltration, the STING agonist is entrapped in the vesicle lumen while the functionalized amphiphilic block polymer is assembled and crosslinked with the amphiphilic block polymer to form a vesicle.

Description

Double-antibody modified vesicle STING agonist, preparation method and application Technical Field The invention relates to the technical field of polymer nano-drugs, in particular to a double-antibody modified vesicle STING agonist, a preparation method and application thereof. Background In recent years, tumor immunotherapy strategies based on T cells, such as immune checkpoint blockade and T cell adaptor, have been advanced in various malignant tumors, but the therapeutic effect thereof depends largely on the adequate infiltration and continuous activation of functional T cells in the tumor microenvironment. However, for most "cold" tumors, the tumor microenvironment is usually represented by an immunosuppressive state, and the T cells are insufficiently infiltrated and subject to functional exhaustion, resulting in lower overall response rates of existing immunotherapeutic approaches and the susceptibility to secondary drug resistance. Activating the interferon gene stimulatory factor (Stimulator of Interferon Genes, STING) signaling pathway has potential advantages in reversing tumor immunosuppression, heating up the tumor microenvironment. The STING agonist can act on the STING, namely the key joint protein of the DNA sensing channel in cells, activate the STING channel and start strong I-type interferon response, not only can directly enhance the immunogenicity of tumor cells, but also can effectively link innate immunity and adaptive immunity by recruiting and activating dendritic cells, thereby promoting the starting, amplifying and infiltrating of tumor-specific T cells. STING agonists have poor cell membrane penetration due to inherent hydrophilicity and charge characteristics, and systemic administration often causes systemic inflammation, resulting in serious toxic side effects. Although the T cell adapter, the immune checkpoint blocking and the STING agonist all have a certain anti-tumor effect, in the prior art, a technical scheme capable of cooperatively integrating a tumor targeting antibody, a T cell targeting antibody and the STING agonist is still lacking, and the scheme not only has an immune checkpoint blocking function and good biological safety, but also can further promote the overall anti-tumor effect through accurate regulation and control of the particle size of a carrier and the proportion of double antibodies. Disclosure of Invention An object of the first aspect of the present invention is to provide a dual antibody modified vesicle STING agonist, which solves the technical problem of poor anti-tumor therapeutic effect in the prior art. Another object of the first aspect of the invention is to ensure an anti-tumour therapeutic effect. It is an object of a second aspect of the present invention to provide the use of a diabody modified vesicle STING agonist. It is an object of a third aspect of the present invention to provide a method for preparing a diabody modified vesicle STING agonist. According to an object of a first aspect of the present invention there is provided a diabody modified vesicle STING agonist comprising: The vesicle is formed by assembling and crosslinking a functionalized amphiphilic block polymer and an amphiphilic block polymer containing a negative electric chain segment, wherein the inner cavity of the vesicle presents electronegativity, the particle size of the vesicle is 20-35 nm, the functionalized amphiphilic block polymer is a functional group-a second hydrophilic chain segment-a second hydrophobic chain segment, and the functional group is N 3 -, mal-or NHS-; STING agonists are loaded into the lumen of the vesicles by electrostatic interactions; the double antibody comprises an anti-HER 2 monoclonal antibody and an anti-PD-1 monoclonal antibody which are respectively and covalently grafted on the surface of the vesicle, wherein the anti-HER 2 monoclonal antibody and the anti-PD-1 monoclonal antibody are both functional group modified antibodies, the functional group is dibenzocyclooctyne, the ratio of the anti-HER 2 monoclonal antibody to the anti-PD-1 monoclonal antibody grafted on the surface of the vesicle is 1 (0.33-3), the anti-HER 2 monoclonal antibody is used for targeting HER2 antigen on the surface of tumor cells, and the anti-PD-1 monoclonal antibody is used for targeting PD-1 antigen on the surface of T cells. Optionally, the STING agonist is selected from any one of diABZI, STING agonist-3, SR-717 or GNE-6468. Optionally, the amphiphilic block polymer is a first hydrophilic segment-a first hydrophobic segment-Ac-KD z, wherein the first hydrophilic segment is polyethylene glycol, the first hydrophobic segment is a random copolymer of trimethylene carbonate monomer and disulfide five-membered ring carbonate monomer, ac is acetyl, KD z is a negative electric segment, K is lysine, D is aspartic acid, and z represents a repeating unit. Optionally, the second hydrophilic segment is polyethylene glycol, and the second hydrophobic segment is a