An All-in-One Nanomedicine Consisting of CRISPR-Cas9 and an Autoantigen Peptide for Restoring Specific Immune Tolerance.

Nanotechnology has shown great promise in treating diverse diseases. However, developing nanomedicines that can cure autoimmune diseases without causing systemic immunosuppression is still quite challenging. Herein, we propose an all-in-one nanomedicine comprising an autoantigen peptide and CRISPR-Cas9 to restore specific immune tolerance by engineering dendritic cells (DCs) into a tolerogenic phenotype, which can expand autoantigen-specific regulatory T (Treg) cells. In brief, we utilized cationic lipid-assisted poly(ethylene glycol)-b-poly(lactide-co-glycolide) (PEG-PLGA) nanoparticles to simultaneously encapsulate an autoimmune diabetes-relevant peptide (2.5mi), a CRISPR-Cas9 plasmid (pCas9), and three guide RNAs (gRNAs) targeting costimulatory molecules (CD80, CD86, and CD40). We demonstrated that the all-in-one nanomedicine was able to effectively codeliver these components into DCs, followed by simultaneous disruption of the three costimulatory molecules and presentation of the 2.5mi peptide on the genome-edited DCs. The resulting tolerogenic DCs triggered the generation and expansion of autoantigen-specific Treg cells by presenting the 2.5mi peptide to CD4+ T cells in the absence of costimulatory signals. Using autoimmune type 1 diabetes (T1D) as a typical disease model, we demonstrated that our nanomedicine prevented autoimmunity to islet components and inhibited T1D development. Our all-in-one nanomedicine achieved codelivery of CRISPR-Cas9 and the peptide to DCs and could be easily applied to other autoimmune diseases by substitution of different autoantigen peptides.

Nanoenabled Reversal of IDO1-Mediated Immunosuppression Synergizes with Immunogenic Chemotherapy for Improved Cancer Therapy.

Certain chemotherapeutics (e.g., oxaliplatin, OXA) can evoke effective antitumor immunity responses by inducing immunogenic cell death (ICD). Unfortunately, tumors always develop multiple immunosuppressive mechanisms, such as the upregulation of immunosuppressive factors, to counteract the effects of immunogenic chemotherapy. Indoleamine 2,3-dioxygenase-1 (IDO1), a tryptophan catabolic enzyme overexpressed in tumor-draining lymph nodes (TDLNs) and tumor tissues, plays a pivotal role in the generation of the immunosuppressive microenvironment. Reversing IDO1-mediated immunosuppression may strengthen the ICD-induced immune response. Herein, we developed a nanoenabled approach for IDO1 pathway interference, which is accomplished by delivering IDO1 siRNA to both TDLNs and tumor tissues with the help of cationic lipid-assisted nanoparticles (CLANs). We demonstrated that the contemporaneous administration of OXA and CLANsiIDO1 could achieve synergetic antitumor effects via promoting dendritic cell maturation, increasing tumor-infiltrating T lymphocytes and decreasing the number of regulatory T cells in a subcutaneous colorectal tumor model. We further proved that this therapeutic strategy is applicable for the treatment of orthotopic pancreatic tumors and offers a strong immunological memory effect, which can provide protection against tumor rechallenge.

Delivery of tacrolimus with cationic lipid-assisted nanoparticles for ulcerative colitis therapy.

Oral drug delivery with nanoparticles has demonstrated great potential for drugs with poor bioavailability. Efficient delivery is possible by overcoming both the mucus and epithelial barrier of the gastrointestinal tract (GIT). Cationic lipid-assisted nanoparticles (CLANs), which are composed of amphiphilic block copolymers and cationic lipids, have been well studied and have been proved beneficial for drug delivery. In this study, CLANs prepared by poly(ethylene glycol)-block-poly(lactic acid) (PEG-b-PLA) and 1,2-dioleoyl-3-trimethylammonium-propanechloride (DOTAP) or N,N-bis(2-hydroxyethyl)-N-methyl-N-(2-cholesteryloxycarbonyl aminoethyl)ammoniumbromide (BHEM-Chol) were used for oral delivery of tacrolimus (FK506) for ulcerative colitis treatment. The average size of these nanoparticles is around 110 nm and the zeta-potential is 35 mV. These nanoparticles maintained their size in buffer solutions of pH 1.2 and 6.8, and slowly release the encapsulated drug. CLANs can be accumulated in the colon and transported through the epithelium in the colitis model by dextran sulfate sodium salt (DSS), leading to attenuation of DSS-induced colitis.

Obtaining More Accurate Signals: Spatiotemporal Imaging of Cancer Sites Enabled by a Photoactivatable Aptamer-Based Strategy.

Early cancer diagnosis is of great significance to relative cancer prevention and clinical therapy, and it is crucial to efficiently recognize cancerous tumor sites at the molecular level. Herein, we proposed a versatile and efficient strategy based on aptamer recognition and photoactivation imaging for cancer diagnosis. This is the first time that a visible light-controlled photoactivatable aptamer-based platform has been applied for cancer diagnosis. The photoactivatable aptamer-based strategy can accurately detect nucleolin-overexpressed tumor cells and can be used for highly selective cancer cell screening and tissue imaging. This strategy is available for both formalin-fixed paraffin-embedded tissue specimens and frozen sections. Moreover, the photoactivation techniques showed great progress in more accurate and persistent imaging to the use of traditional fluorophores. Significantly, the application of this strategy can produce the same accurate results in tissue specimen analysis as with classical hematoxylin-eosin staining and immunohistochemical technology.