Described herein are compositions and techniques related to generation and therapeutic application of artificial synapses. Artificial synapses are engineered extracellular vesicles, including exosomes, which incorporate sticky binders on their surface to anchor signaling domains against biological targets, such as receptors. These engineered additives can be organized in genetic vector constructs, expressed in mammalian cells, wherein the sticky binders attach to extracellular vesicles such as exosomes, thereby presenting their joined signaling domains which are rapidly taken up by recipient cells. Artificial synapses adopt the hallmark biophysical and biochemical features of extracellular vesicles, allowing for rapid deployment and scale-up. Importantly, this strategy can allow for kinetically favorable signal generation and signal propagation. This includes, for example, increasing density of agonist presentation to support receptor clustering—an onerous barrier for traditional receptor targeting strategies.

The present disclosure provides, at least in part, methods and compositions for in vivo fusosome delivery. In some embodiments, the fusosome comprises a combination of elements that promote specificity for target cells, e.g., one or more of a fusogen, a positive target cell-specific regulatory element, and a non-target cell-specific regulatory element. In some embodiments, the fusosome comprises one or more modifications that decrease an immune response against the fusosome.

An engineered phage-derived particle (PDP) for expressing a transgene in a target cell transduced with a bacteriophage, the PDP includes (i) less than about 500 bp of DNA from the bacteriophage genome, (ii) an ITR-flanked therapeutic gene up to 20 kb, (iii) an endosomal escape sequence, (iv) a nuclear localization sequence, and (v) a cell-specific targeting moiety. The PDP may escape lysosomal degradation, traffic across the nuclear envelope and expressed a therapeutic gene in a mammalian cell.

Several gastrointestinal and gynecological malignancies have the potential to disseminate and grow in the peritoneal cavity. The occurrence of peritoneal carcinomatosis (PC) has been shown to significantly decrease overall survival in patients. Treatment of residual microscopic disease remains a challenge with new anticancer modalities development. Now, the inventors propose an innovative therapeutic management of peritoneal carcinomatosis (PC) that is bio-inspired and tumor-targeted by engineering MSC-derived EVs to encapsulate a photosensitizer (mTHPC) for improved photodynamic therapy efficiency and safety. In this work, the inventors first evaluated the biodistribution of EVs-mTHPC in a murine PC model and highlighted superior accumulation of mTHPC in the tumor compared to other mTHPC formulations (free drug and liposomal one (Foslip®). The effectiveness of PDT mediated by mTHPC vectorized in EVs has then been evaluated in PC. In accordance with pharmacokinetics, the results revealed both an enhanced light-induced therapeutic efficiency in terms of tumoral cytotoxicity, safety for surrounding tissue after laser irradiation, immunomodulation and improved survival time. Thus, the present invention relates to mesenchymal stem cell derived extracellular vesicles loaded with at least one photosensitizer and uses thereof for the treatment of peritoneal carcinomatosis.

Methods and composition for cell-based therapy as well as somatostatin receptor-based therapy are described. For example, in certain aspects methods for administering an anti-tumor therapy using a signaling defective somatostatin receptor mutant are described. Furthermore, the invention provides compositions and methods involve a somatostatin constitutively active somatostatin receptor mutant.

In alternative embodiments, the invention provides methods for treating, ameliorating or protecting (preventing) an individual or a patient against a disease, an infection or a condition responsive to an increased paracrine polypeptide level in vivo comprising: providing a paracrine polypeptide-encoding nucleic acid or gene operatively linked to a transcriptional regulatory sequence; or an expression vehicle, a vector, a recombinant virus, or equivalent, having contained therein a paracrine-encoding nucleic acid or gene, and the expression vehicle, vector, recombinant virus, or equivalent can express the paracrine-encoding nucleic acid or gene in a cell or in vivo; and administering or delivering the paracrine polypeptide-encoding nucleic acid or gene operatively linked to a transcriptional regulatory sequence, or the expression vehicle, vector, recombinant virus, or equivalent, to an individual or a patient in need thereof, thereby treating, ameliorating or protecting (preventing) the individual or patient against the disease, infection or condition responsive to an increased paracrine polypeptide level.

The present invention provides preparations of MSCs with important therapeutic potential. The MSC cells are non-primary cells with an antigen profile comprising less than about 1.25% CD45+ cells (or less than about 0.75% CD45+), at least about 95% CD105+ cells, and at least about 95% CD166+ cells. Optionally, MSCs of the present preparations are isogenic and can be expanded ex vivo and cryopreserved and thawed, yet maintain a stable and uniform phenotype. Methods are taught here of expanding these MSCs to produce a clinical scale therapeutic preparations and medical uses thereof.

Methods, systems, compositions and strategies for the use of ARMM-mediated delivery of molecules (e.g., biological molecules, small molecules, proteins, and nucleic acids (e.g., DNA, RNA), DNA plasmids shRNA, mRNA) to cells of the nervous system (e.g., central nervous system and peripheral nervous system).

Compositions comprising donor cells, acceptor cells, membrane-enclosed bodies and methods are described herein.

This disclosure provides compositions and methods for delivering a viral composition to cells, e.g., for cell surface receptor-mediated uptake, and enhanced viral transduction. Viral transduction can be achieved via a bifunctional bridging composition that includes a moiety that binds to a cell surface receptor ligand and a linked bridging moiety that binds to a viral composition. Also provided are modified viral compositions comprising a bridging composition specifically bound via its bridging moiety to the viral composition. Modified viral compositions and methods for reducing levels or titers of neutralizing antibodies in a subject in need of viral therapy, e.g., gene therapy, are provided. In some embodiments, the modified viral composition includes empty viral particles that bind and internalize neutralizing autoantibodies. Modified viral compositions including empty viral particles can be administered prior to viral therapy. Also provided are pharmaceutical compositions and kits including a bifunctional bridging composition and/or modified viral compositions.