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Publications (2)8.06 Total impact

  • Article: Development of human hepatocellular carcinoma cell-targeted protein cages.
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    ABSTRACT: We described herein a human hepatocellular carcinoma (HCC) cell-targeted protein cage for which the HCC-binding peptide termed SP94 was modified at the surface of a naturally occurred heat shock protein (Hsp) cage. Six types of HCC-targeted Hsp cages were chemically synthesized using two types of heterobifunctional linker (SM(PEG)(n)) with different lengths and two types of SP94 peptide, which contained a unique Cys residue at the N- or C-terminus of the peptide. These Hsp cages were characterized using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-ToF MS) analyses, sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analyses, and dynamic light scattering (DLS) measurement. Fluorescence microscopic observations revealed that all the engineered protein cages bind selectively to HCC cells but not to the other cell lines tested (including normal liver cell). Moreover, the number of SP94 peptides on Hsp cages, conjugation site of SP94 peptide, and linker length between a Hsp cage and a SP94 peptide had important effects upon the binding of engineered Hsp cages to HCC cells. An engineered Hsp cage conjugated to the N-terminus of SP94 peptide via a longer linker molecule and containing high SP94 peptide levels showed greater binding toward HCC cells. Surprisingly, through optimization of these three factors, up to 10-fold greater affinity toward HCC cells was achieved. These results are critically important not only for the development of HCC cell-targeting devices using SP94 peptide, but also to create other cell-targeting materials that utilize other peptide ligands.
    Bioconjugate Chemistry 05/2012; 23(7):1494-501. · 4.93 Impact Factor
  • Article: Liver cell specific targeting by the preS1 domain of hepatitis B virus surface antigen displayed on protein nanocages.
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    ABSTRACT: Protein nanocages are self-organized complexes of oligomers whose three-dimensional architecture can been determined in detail. These structures possess nanoscale inner cavities into which a variety of molecules, including therapeutic or diagnostic agents, can be encapsulated. These properties yield these particles suitable for a new class of drug delivery carrier, or as a bioimaging reagent that might respond to biochemical signals in many different cellular processes. We report here the design, synthesis, and biological characterization of a hepatocyte-specific nanocage carrying small heat-shock protein. These nanoscale protein cages, with a targeting peptide composed of a preS1 derivative from the hepatitis B virus on their surfaces, were prepared by genetic engineering techniques. PreS1-carrying nanocages showed lower cytotoxicity and significantly higher specificity for human hepatocyte cell lines than other cell lines in vitro. These results suggested that small heat-shock protein-based nanocages present great potential for the development of effective targeted delivery of various agents to specific cells.
    International Journal of Nanomedicine 01/2012; 7:4353-62. · 3.13 Impact Factor