PEGylated immunoliposome-loaded endoglin single-chain antibody enhances anti-tumor capacity of porcine α1,3GT gene

Biomaterials. 2019 Oct:217:119231. doi: 10.1016/j.biomaterials.2019.119231. Epub 2019 Jun 14.

Abstract

Tumor could not be completely removed due to the absence of immune storm against tumor. The porcine α1,3 galactosyltransferase (α1,3 GT) induce the hyperacute rejection by synthesizing Galα1-3Galβ1-(3)4GlcNAc-R (αGal) on the surface of graft endothelial cells (ECs) during xeno-transplantation. This study aimed to develop anti-endoglin single-chain Fv fragments (ENG-scFv) conjugated PEGylated immunoliposomes (iLPs) to induce immune storm against tumor. Immune fluorescence was performed to detect the binding of ENG-scFv to human ENG, the endosomal/lysosomal escape of ENG-scFv-iLPs/α1,3 GT, and αGal expression in hENG-HEK293 cells. In vitro MTT assay was performed to measure ENG-scFv-iLPs/α1,3 GT cytotoxicity. NOD/SCID mouse born A549 tumor model was used to evaluate the therapeutic potency of ENG-scFv-iLPs/α1,3 GT. ENG-scFv-iLPs enabled efficient targeting delivery of α1,3 GT plasmid to ENG + tumors neovascular endothelial cells (TnECs), promoted endosomal/lysosomal escape due to the pH-sensitive ability, then synthesized carbohydrate epitope αGal on the surface of these cells to achieve the purpose of destroying the tumor. The mechanism of uptake for nanoparticles was energy driven, the clathrin-mediated endocytosis was the main endocytic pathway of the ENG-mAb-iLPs/α1,3 GT and lipid-raft-mediated of the ENG-scFv-iLPs/α1,3 GT, and macropinocytosis was also involved in intracellular entry. The inhibition of tumor angiogenesis and proliferation by ENG-scFv-iLPs/α1,3 GT was closely related to down-regulation of VEGF. Our findings establish an alternative therapeutic paradigm for scFv-conjugated nanoparticles to induce tumor cell apoptosis and inhibit tumor growth early. Such iLPs nanocarrier could efficiently release α1,3 GT to their distinct sites of action, where the endoglin + tumor neovascular endothelial cells (ENG + TnECs) exist, in a site-specific manner. Therefore, we believe that these scFv-targeted core-shell immunocomplexes are an important potential α1,3 GT delivery system for various solid tumor-targeted therapy.

Keywords: Cancer-targeted therapy; Endoglin; PEGylation; Single-chain antibody; α1,3 GT gene.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylglucosamine / metabolism
  • Animals
  • Cell Death
  • Cell Line, Tumor
  • Cell Membrane / metabolism
  • Cell Nucleus / metabolism
  • Cytokines / metabolism
  • Endocytosis
  • Endoglin / chemistry
  • Endoglin / immunology*
  • Endosomes / metabolism
  • Galactosyltransferases / genetics*
  • HEK293 Cells
  • Human Umbilical Vein Endothelial Cells / metabolism
  • Humans
  • Hydrogen-Ion Concentration
  • Liposomes
  • Lysosomes / metabolism
  • Mice, Inbred NOD
  • Mice, SCID
  • Nanoparticles / chemistry
  • Nanoparticles / ultrastructure
  • Neoplasms / pathology
  • Neoplasms / therapy*
  • Neovascularization, Pathologic / metabolism
  • Polyethylene Glycols / chemistry*
  • Protein Domains
  • Single-Chain Antibodies / immunology*
  • Swine
  • Tissue Distribution

Substances

  • Cytokines
  • Endoglin
  • Liposomes
  • Single-Chain Antibodies
  • Polyethylene Glycols
  • Galactosyltransferases
  • N-acetyllactosaminide alpha-1,3-galactosyltransferase
  • Acetylglucosamine