Targeted co-delivery of Trp-2 polypeptide and monophosphoryl lipid A by pH-sensitive poly (ß-amino ester) nano-vaccines for melanoma.

Dendritic cell (DC)-targeted vaccines based on nanotechnology are a promising strategy to efficiently induce potent immune responses. We synthesized and manufactured a mannose-modified poly (ß-amino ester) (PBAE) nano-vaccines with easily tuneable and pH-sensitive characteristics to co-deliver the tumor-associated antigen polypeptide Trp-2 and the TLR4 agonist monophosphoryl lipid A (MPLA). To reduce immunosuppression in the tumor microenvironment, an immune checkpoint inhibitor, PD-L1 antagonist, was administrated along with PBAE nano-vaccines to delay melanoma development. We found that mannosylated Trp-2 and MPLA-loaded PBAE nano-vaccines can target and mature DCs, consequently boosting antigen-specific cytotoxic T lymphocyte activity against melanoma. The prophylactic study indicates that combination therapy with PD-L1 antagonist further enhanced anti-tumor efficacy by 3.7-fold and prolonged median survival time by 1.6-fold more than free Trp-2/MPLA inoculation. DC-targeting PBAE polymers have a great potential as a nanotechnology platform to design vaccines and achieve synergistic anti-tumor effects with immune checkpoint therapy.

Stem Cells and Bone Tissue Engineering.

Segmental bone defects that are caused by trauma, infection, tumor resection, or osteoporotic fractures present significant surgical treatment challenges. Host bone autograft is considered the gold standard for restoring function but comes with the cost of harvest site comorbidity. Allograft bone is a secondary option but has its own limitations in the incorporation with the host bone as well as its cost. Therefore, developing new bone tissue engineering strategies to treat bone defects is critically needed. In the past three decades, the use of stem cells that are delivered with different scaffolds or growth factors for bone tissue engineering has made tremendous progress. Many varieties of stem cells have been isolated from different tissues for use in bone tissue engineering. This review summarizes the progress in using different postnatal stem cells, including bone marrow mesenchymal stem cells, muscle-derived stem cells, adipose-derived stem cells, dental pulp stem cells/periodontal ligament stem cells, periosteum stem cells, umbilical cord-derived stem cells, peripheral blood stem cells, urine-derived stem cells, stem cells from apical papilla, and induced pluripotent stem cells, for bone tissue engineering and repair. This review also summarizes the progress using exosomes or extracellular vesicles that are delivered with various scaffolds for bone repair. The advantages and disadvantages of each type of stem cell are also discussed and explained in detail. It is hoped that in the future, these preclinical results will translate into new regenerative therapies for bone defect repair.

Application of seed mucilage as functional biopolymer in meat product processing and preservation.

Meat products consumption is rising globally, but concerns about sustainability, fat content, and shelf life. Synthetic additives and preservatives used for extending the shelf life of meat often carry health and environmental drawbacks. Seed mucilage, natural polysaccharides, possesses unique functional properties like water holding, emulsifying, and film forming, offering potential alternatives in meat processing and preservation. This study explores the application of seed mucilage from diverse sources (e.g., flaxseed, psyllium, basil) in various meat and meat products processing and preservation. Mucilage's water-holding and emulsifying properties can potentially bind fat and decrease the overall lipid content in meat and meat-based products. Moreover, antimicrobial and film-forming properties of mucilage can potentially inhibit microbial growth and reduce oxidation, extending the shelf life. This review emphasizes the advantages of incorporating mucilage into processing and coating strategies for meat and seafood products.

The coupling effect of cellulose nanocrystal and strong shear field achieved the strength and toughness balance of Polylactide.

Up to now, unbalanced mechanical properties and poor heat resistance have become two major problems of polylactic acid (PLA). In this study, the coupling between Cellulose nanocrystal (CNC) and strong shearing field formed a unique hierarchical structure. Compared with pure PLA, the tensile strength of DPIM PLA/CNC increased from 57.9 MPa to 79.6 MPa without sacrificing the toughness of PLA, and the vicat softening temperature of DPIM PLA/CNC increased from 60 °C to 155 °C. The microstructure of PLA/CNC composites was analyzed by SEM, SAXS and WAXD, and it was found that the coupling effect of CNC and strong shear flow field could significantly change the crystallization behavior of PLA. CNC could increase PLA shish length from 251 nm to 889 nm under the action of shear field. At the same time, due to this coupling effect, more PLA shish-kebab structures were induced at the interface. This special hierarchical structure composed of CNC and PLA Shish-Kebab is of great significance and can provide important guidance for achieving the balance of strength and toughness of polymer materials.

Oxymatrine loaded nitric oxide-releasing liposomes for the treatment of ulcerative colitis.

Oxymatrine (OM) is the biologically active ingredient of Chinese medicinal herb Sophora flavescens, which is reported to be effective on alleviating ulcerative colitis (UC) due to its anti-inflammatory property. However, its highly effective dose is an obstacles to its application. Therefore, liposome was used to encapsulate OM, realize targeting delivery to colitis and thus reduce drug dosage. Meanwhile, considering the potential anti-inflammatory ability of nitric oxide (NO), a NO donor, d-α-tocopheryl polyethylene glycol succinate nitrate (TN), was introduced into the liposomal system and OM loaded NO-releasing liposomes (OM@TN-lip) were prepared in order to co-deliver OM and NO to the inflammatory lesions of DSS-induced UC mice to achieve the combination therapy. OM@TN-lip was multilamelar sphere with the encapsulation efficiency of ~70%, the diameter of ~200 nm and ζ-potential of about -13 mV. Bio-distribution results revealed the liposomes could efficiently accumulate in the inflammatory colon by diffusion and maintain for more than 36 h. In UC mice model, OM@TN-lip showed significant alleviation of inflammation and the treatment was highly related to down-regulation of pro-inflammatory cytokines TNF-α, IFN-γ, IL-1ß and IL-6, decrease of macrophages infiltration, activity decrease of myeloperoxidase (MPO) and cyclooxygenase-2 (COX-2), and rebuilding antioxidant/oxidation balance by reducing reactive oxygen species (ROS) and increasing Glutathione (GSH) in colon.

Hyperbranched poly(ß-amino ester) based polyplex nanopaticles for delivery of CRISPR/Cas9 system and treatment of HPV infection associated cervical cancer.

Persistent high-risk HPV infection is the main factor for cervical cancer. HPV E7 oncogene plays an important role in HPV carcinogenesis. Down-regulation of E7 oncogene expression could induce growth inhibition in HPV-positive cells and thus treats HPV related cervical cancer. Here we developed a non-virus gene vector based on poly(amide-amine)-poly(ß-amino ester) hyperbranched copolymer (hPPC) for the delivery of CRISPR/Cas9 system to specifically cleave HPV E7 oncogene in HPV-positive cervical cancer cells. The diameter of polyplex nanoparticles (NPs) formed by hPPCs/linear poly(ß-amino ester) (PBAE) and plasmids were approximately 300 nm. These hPPCs/PBAE-green fluorescence protein plasmids polyplex NPs showed high transfection efficiency and low toxicity in cells and mouse organs. By cleaving HPV16 E7 oncogene, reducing the expression of HPV16 E7 protein and increasing intracellular retinoblastoma 1 (RB1) amount, hPPCs/PBAE-CRISPR/Cas9 therapeutic plasmids polyplex NPs, especially highly branched hPPC1-plasmids polyplex NPs, exhibited strong growth inhibition of cervical cancer cells in vitro and xenograft tumors in nude mice. Together, the hPPCs/PBAE polyplex NPs to deliver HPV16 E7 targeted CRISPR/Cas9 system in this study could potentially be applied to treat HPV-related cervical cancer.

An effective vaginal gel to deliver CRISPR/Cas9 system encapsulated in poly (ß-amino ester) nanoparticles for vaginal gene therapy.

BACKGROUND: Gene therapy has held promises for treating specific genetic diseases. However, the key to clinical application depends on effective gene delivery. METHODS: Using a large animal model, we developed two pharmaceutical formulations for gene delivery in the pigs' vagina, which were made up of poly (ß-amino ester) (PBAE)-plasmid polyplex nanoparticles (NPs) based two gel materials, modified montmorillonite (mMMT) and hectorite (HTT). FINDINGS: By conducting flow cytometry of the cervical cells, we found that PBAE-GFP-NPs-mMMT gel was more efficient than PBAE-GFP-NPs-HTT gel in delivering exogenous DNA intravaginally. Next, we designed specific CRISPR/SpCas9 sgRNAs targeting porcine endogenous retroviruses (PERVs) and evaluated the genome editing efficacy in vivo. We discovered that PERV copy number in vaginal epithelium could be significantly reduced by the local delivery of the PBAE-SpCas9/sgRNA NPs-mMMT gel. Comparable genome editing results were also obtained by high-fidelity version of SpCas9, SpCas9-HF1 and eSpCas9, in the mMMT gel. Further, we confirmed that the expression of topically delivered SpCas9 was limited to the vagina/cervix and did not diffuse to nearby organs, which was relatively safe with low toxicity. INTERPRETATION: Our data suggested that the PBAE-NPs mMMT vaginal gel is an effective preparation for local gene therapy, yielding insights into novel therapeutic approaches to sexually transmitted disease in the genital tract. FUNDING: This work was supported by the National Science and Technology Major Project of the Ministry of science and technology of China (No. 2018ZX10301402); the National Natural Science Foundation of China (81761148025, 81871473 and 81402158); Guangzhou Science and Technology Programme (No. 201704020093); National Ten Thousand Plan-Young Top Talents of China, Fundamental Research Funds for the Central Universities (17ykzd15 and 19ykyjs07); Three Big Constructions-Supercomputing Application Cultivation Projects sponsored by National Supercomputer Center In Guangzhou; the National Research FFoundation (NRF) South Africa under BRICS Multilateral Joint Call for Proposals; grant 17-54-80078 from the Russian Foundation for Basic Research.

TMTP1-modified Indocyanine Green-loaded Polymeric Micelles for Targeted Imaging of Cervical Cancer and Metastasis Sentinel Lymph Node in vivo.

Metastasis is one of the most threatening aspects of cervical cancer. We developed a method to intraoperatively map the primary tumor, metastasis and metastatic sentinel lymph nodes (SLNs), providing real-time intraoperative guidance in cervical cancer. Methods: TMTP1, a tumor metastasis targeting peptide, was employed to modify the indocyanine green (ICG)-loaded poly (ethylene glycol)- poly (lactic-co-glycolic acid) (PEG-PLGA) micelles. The cervical cancer subcutaneous tumor model and lung metastasis model were established to determine the active targeting of ICG-loaded TMTP1-PEG-PLGA micelles (ITM) for the primary tumor and occult metastasis of cervical cancer. Human cervical cancer HeLa cells engineered by firefly luciferase were injected into the right hocks of BALB/c nude mice to develop the SLN metastasis model. The ITM and control ICG-loaded PEG-PLGA micelles (IM) were injected into the right hind footpads in the SLN metastasis model, and the migration and retention of micelles were recorded under near-infrared fluorescence. K14-HPV16 transgenic mice were also used to detect the image capability of ITM to target cancerous lesions. Results: ITM could actively target imaging of the primary tumor and cervical cancer metastasis. ITM quickly diffused from the injection site to SLNs along lymphatic capillaries and remained in the SLNs for 12 h. Moreover, ITM specifically accumulated in the tumor metastatic SLNs (T-SLNs), which could be successfully distinguished from normal SLNs (N-SLNs). Conclusion: ITM could achieve active targeting of the primary tumor, metastasis and T-SLNs, providing precise and real-time intraoperative guidance for cervical cancer.

Biodegradable Hollow Mesoporous Silica Nanoparticles for Regulating Tumor Microenvironment and Enhancing Antitumor Efficiency.

There is accumulating evidence that regulating tumor microenvironment plays a vital role in improving antitumor efficiency. Herein, to remodel tumor immune microenvironment and elicit synergistic antitumor effects, lipid-coated biodegradable hollow mesoporous silica nanoparticle (dHMLB) was constructed with co-encapsulation of all-trans retinoic acid (ATRA), doxorubicin (DOX) and interleukin-2 (IL-2) for chemo-immunotherapy. The nanoparticle-mediated combinational therapy provided a benign regulation on tumor microenvironment through activation of tumor infiltrating T lymphocytes and natural killer cells, promotion of cytokines secretion of IFN-γ and IL-12, and down-regulation of immunosuppressive myeloid-derived suppressor cells, cytokine IL-10 and TGF-ß. ATRA/DOX/IL-2 co-loaded dHMLB demonstrated significant tumor growth and metastasis inhibition, and also exhibited favorable biodegradability and safety. This nanoplatform has great potential in developing a feasible strategy to remodel tumor immune microenvironment and achieve enhanced antitumor effect.