High-Throughput Screening of Surface Engineered Cyanine Nanodots for Active Transport of Therapeutic Antibodies into Solid Tumor

Amino-Acid-Encoded Supramolecular Nanostructures for Persistent Bioluminescence Imaging of Tumor

Bioluminescence imaging (BLI) is a powerful technique for noninvasive monitoring of biological processes and cell transplantation. Nonetheless, the application of D-luciferin, which is widely employed as a bioluminescent probe, is restricted in long-term in vivo tracking due to its short half-life. This study presents a novel approach using amino acid-encoded building blocks to accumulate and preserve luciferin within tumor cells, through a supramolecular self-assembly strategy. The building block platform called Cys(SEt)-X-CBT (CXCBT, with X representing any amino acid) utilizes a covalent-noncovalent hybrid self-assembly mechanism to generate diverse luciferin-containing nanostructures in tumor cells after glutathione reduction. These nanostructures exhibit efficient tumor-targeted delivery as well as sequence-dependent well-designed morphologies and prolonged bioluminescence performance. Among the selected amino acids (X = Glu, Lys, Leu, Phe), Cys(SEt)-Lys-CBT (CKCBT) exhibits the superior long-lasting bioluminescence signal (up to 72 h) and good biocompatibility. This study demonstrates the potential of amino-acid-encoded supramolecular self-assembly as a convenient and effective method for developing BLI probes for long-term biological tracking and disease imaging.

Temporal Patterns of Angular Displacement of Endosomes: Insights into Motor Protein Exchange Dynamics

The material transport system, facilitated by motor proteins, plays a vital role in maintaining a non-equilibrium cellular state. However, understanding the temporal coordination of motor protein activity requires an advanced imaging technique capable of measuring 3D angular displacement in real-time. In this study, a Fourier transform-based plasmonic dark-field microscope has been developed using anisotropic nanoparticles, enabling the prolonged and simultaneous observation of endosomal lateral and rotational motion. A sequence of discontinuous 3D angular displacements has been observed during the pause and run phases of transport. Notably, a serially correlated temporal pattern in the intermittent rotational events has been demonstrated during the tug-of-war mechanism, indicating Markovian switching between the exploitational and explorational modes of motor protein exchange prior to resuming movement. Alterations in transition frequency and the exploitation-to-exploration ratio upon dynein inhibitor treatment highlight the relationship between disrupted motor coordination and reduced endosomal transport efficiency. Collectively, these results suggest the importance of orchestrated temporal motor protein patterns for efficient cellular transport.

Effect of biophysical properties of tumor extracellular matrix on intratumoral fate of nanoparticles: Implications on the design of nanomedicine

Nanomedicine has a profound impact on various research domains including drug delivery, diagnostics, theranostics, and regenerative medicine. Nevertheless, the clinical translation of nanomedicines for solid cancer remains limited due to the abundant physiological and pathological barriers in tumor that hinder the intratumoral penetration and distribution of these nanomedicines. In this article, we review the dynamic remodeling of tumor extracellular matrix during the tumor progression, discuss the impact of biophysical obstacles within tumors on the penetration and distribution of nanomedicines within the solid tumor and collect innovative approaches to surmount these obstacles for improving the penetration and accumulation of nanomedicines in tumor. Furthermore, we dissect the challenges and opportunities of the respective approaches, and propose potential avenues for future investigations. The purpose of this review is to provide a perspective guideline on how to effectively enhance the penetration of nanomedicines within tumors using promising methods.

Development of a novel cholesterol tag-based system for trans-membrane transport of protein drugs

The main technological difficulties of developing an intracellular (transmembrane) transport system for protein drugs lie in two points: i) overcoming the barriers in the cellular membrane, and ii) loading enough protein drugs, and particularly high-dose proteins, into particles. To address these two technological problems, we recently developed a novel cholesterol tag (C-Tag)-based transmembrane transport system. This pilot study found that the C-Tag dramatically improved the cellular uptake of Fab (902-fold, vs. Fab alone) into living cells, indicating that it successfully achieved transmembrane transport. Moreover, C-Tag-mediated membrane transport was verified using micron-scale large unilamellar vesicles (LUVs, approximately 1.5 μm)-based particles. The C-Tagged Fab was able to permeate the liposomal bilayer and it greatly enhanced (a 10.1-fold increase vs. Fab alone) internalization of proteins into the LUV-based particles, indicating that the C-Tag loaded enough proteins into particles for use of high-dose proteins. Accordingly, we established a novel C-Tag-based transport system that has overcome the known technological difficulties of protein transmembrane delivery, and this might be a useful technology for drug development in the future.

Single-Molecule Dendritic MRI Nanoprobes Reveal the Size-Dependent Tumor Entrance

The tumor entrance of drug delivery systems, including therapeutic proteins and nanomedicine, plays an essential role in affecting the treatment outcome. Nanoparticle size is a critical but contradictory factor in making a trade-off among blood circulation, tumor accumulation, and penetration. Here, this work designs a series of single-molecule gadolinium (Gd)-based magnetic resonance imaging (MRI) nanoprobes with well-defined sizes to precisely explore the size-dependent tumor entrance in vivo. The MRI nanoprobes obtained by divergent synthesis contain a core molecule of macrocyclic Gd(III)-chelate and different layers of dendritic lysine units, mimicking globular protein. This work finds that the r1 relaxivity and MR imaging signals increase with the nanoparticle size. The nanoprobe with a lower limit of critical size threshold ≈8.0 nm achieves superior tumor accumulation and penetration. These single-molecule MRI nanoprobes can be served to precisely examine the size-related nanoparticle-biological interactions.