Yuefei Wang,Renliang Huang,Wei Qi,Yanyan Xie,Mengfan Wang,Rongxin Su,Zhimin He
The wetting and drying of drops on flexible fibers occurs ubiquitously in nature, and the capillary force underlying this phenomenon has motivated our great interest in learning how to direct supramolecular self-assembly. Here, the hierarchical co-assembly of two aromatic peptides, diphenylalanine (FF) and ferrocene-diphenylalanine (Fc-FF), is reported via sequential, combinatorial assembly. The resulting dandelion-like microstructures have highly complex architectures, where FF microtube arrays serve as the scapes and the Fc-FF nanofibers serve as the flower heads. Homogeneous FF microtubes with diameters tailored between 1 and 9 μm and wall thickness ranging from 70 to 950 nm are initially formed by controlling the degree of supersaturation of the FF and the water content. Once the FF microtubes are formed, the growth of the dandelion-like microstructures is then driven by the capillary force, derived from the wetting and drying of the Fc-FF solution on the FF microtubes. This simple and ingenious strategy offers many opportunities to develop new and creative methods for controlling the hierarchical self-assembly of peptides and thus building highly complex nano and microstructures.
Ju Liang,Runfa Guo,Maosong Xuan,Qiankun Sun,Wenlan Wu
Purpose This study aimed to construct a DOX conjugate with liver tumor targeting and acid sensitivity based on a short aromatic peptide FFYEE, which could amplify the tumor inhibition efficacy of DOX and alleviate tissue toxicity. Methods A novel DOX-peptide conjugate, D-gal-FFYEE-hyd-DOX, was constructed by linking DOX to the side chain of FFYEE with acid-sensitive hydrazone bond and by modifying the C-terminal of peptide with α-D-galactosamine (D-gal) as targeting ligand. The structure of D-gal-FFYEE-hyd-DOX was characterized by mass spectrometry, infrared spectroscopy (IR), and UV-Vis spectroscopy (UV-Vis). The assembly characteristics of pentapeptide FFYEE and D-gal-FFYEE-hyd-DOX were observed by transmission electron microscope (TEM). In vitro drug release, cytotoxicity, endocytosis, in vivo antitumor experiment and histopathology analysis were investigated. Results Peptide FFYEE endowed the D-gal-FFYEE-hyd-DOX with self-assembly performance and improved biocompatibility. D-gal-FFYEE-hyd-DOX can self-assemble into nanofibers with a diameter of ~ 40 nm in neutral aqueous solution and significantly reduced the cytotoxicity of free DOX to L02 cells. In vitro drug release results showed that D-gal-FFYEE-hyd-DOX had acid sensitivity and controlled release characteristics. The cytotoxicity and endocytosis investigations confirmed that D-gal-FFYEE-hyd-DOX enhanced the cellular uptake of DOX and inhibition effect on HepG2 cells. In vivo antitumor experiment indicated that D-gal-FFYEE-hyd-DOX could significantly inhibit the growth of liver tumor in mice and reduce the side effects of DOX. Conclusion The conjugate D-gal-FFYEE-hyd-DOX with liver tumor targeting and acid sensitivity has the characteristics of strong tumor inhibition and low toxicity, hinting the great clinical application potential for targeted delivery of DOX in cancer treatment.
Compared with vaccines comprising inactivated or attenuated whole pathogens, the subunit vaccines based on protein antigens are safer and easier to manufacture. Yet subunit vaccines usually exhibit weak and nondurable immune responses, which is mainly due to their poor uptake by antigen-presenting cells. To address this issue, we develop a fluorinated aromatic peptide (F-AP), in which electronegativity of fluorine is to enhance its affinity with antigens and ability of transmembrane. In mice model, F-AP demonstrated over 4-fold and 501-fold higher antibody titers than AP and conventional aluminum adjuvant, respectively. Consistent with the antibody responses, F-AP greatly promoted the proliferation of T follicular helper cell and mature B cell. Intriguingly, conventional type 1 dendritic cells (cDC1) were also increased in lymph nodes with F-AP vaccination. And antigens localization experiments showed that F-AP help antigens escape from cell lysosomes, indicating that F-AP could potentially induce cellular immune responses through cDC1′s antigen cross-presentation function. Collectively, the data suggest that simple fluorine group modification on aromatic peptide, F-AP, could improve the immune response of subunit antigens. Thus, fluoridation strategy may provide a novel approach for nanomaterials enhancing the vaccination immune response of vaccines or immunotherapies.