The identification of low-frequency antigen-specific CD4 T cells is crucial for effective immunomonitoring across various diseases. However, this task still encounters experimental challenges necessitating the implementation of enrichment procedures. While existing antigen-specific expansion technologies predominantly concentrate on the enrichment of CD8 T cells, advancements in methods targeting CD4 T cells have been limited.
View Article and Find Full Text PDFPhotodynamic therapy (PDT) for deep-seated tumors is still challenging due to the limited penetration of visible light through tissues. To resolve this limitation, systems based on bioluminescence resonance energy transfer (BRET), that do not require an external light source are proposed. Herein, for BRET-activated PDT we developed proteinaceous BRET-pair consisting of luciferase NanoLuc, which acts as energy donor upon addition of luciferase specific substrate furimazine, and phototoxic protein SOPP3 as a photosensitizer.
View Article and Find Full Text PDFPeptide nucleic acid (PNA) may be used in various biomedical applications; however, these are currently limited, due to its low solubility in aqueous solutions. In this study, a methodology to overcome this limitation is demonstrated, as well as the effect of PNA on cell viability. We show that extruding a mixture of natural phospholipids and short (6-22 bases), cytosine-rich PNA through a 100 nm pore size membrane under mild acidic conditions resulted in the formation of small (60-90 nm in diameter) multilamellar vesicles (SMVs) comprising several (3-5) concentric lipid membranes.
View Article and Find Full Text PDFPhotodynamic therapy (PDT) is one of the most appealing photonic modalities for cancer treatment based on anticancer activity of light-induced photosensitizer-mediated reactive oxygen species (ROS), but a limited depth of light penetration into tissues does not make possible the treatment of deep-seated neoplasms and thus complicates its widespread clinical adoption. Here, we introduce the concept of genetically encoded bioluminescence resonance energy transfer (BRET)-activated PDT, which combines an internal light source and a photosensitizer (PS) in a single-genetic construct, which can be delivered to tumors seated at virtually unlimited depth and then triggered by the injection of a substrate to initiate their treatment. To illustrate the concept, we engineered genetic NanoLuc-miniSOG BRET pair, combining NanoLuc luciferase flashlight and phototoxic flavoprotein miniSOG, which generates ROS under luciferase-substrate injection.
View Article and Find Full Text PDFBarnase is an extracellular ribonuclease secreted by that was originally studied as a small stable enzyme with robust folding. The identification of barnase intracellular inhibitor barstar led to the discovery of an incredibly strong protein-protein interaction. Together, barnase and barstar provide a fully genetically encoded toxin-antitoxin pair having an extremely low dissociation constant.
View Article and Find Full Text PDFNear-infrared phototherapy has great therapeutic potential for cancer treatment. However, for efficient application, in vivo photothermal agents should demonstrate excellent stability in blood and targeted delivery to pathological tissue. Here, we demonstrated that stable bovine serum albumin-coated gold mini nanorods conjugated to a HER2-specific designed ankyrin repeat protein, DARPin_9-29, selectively accumulate in HER2-positive xenograft tumors in mice and lead to a strong reduction in the tumor size when being illuminated with near-infrared light.
View Article and Find Full Text PDFCancer cells frequently overexpress specific surface receptors providing tumor growth and survival which can be used for precise therapy. Targeting cancer cell receptors with protein toxins is an attractive approach widely used in contemporary experimental oncology and preclinical studies. Methods of targeted delivery of toxins to cancer cells, different drug carriers based on nanosized materials (liposomes, nanoparticles, polymers), the most promising designed light-activated toxins, as well as mechanisms of the cytotoxic action of the main natural toxins used in modern experimental oncology, are discussed in this review.
View Article and Find Full Text PDFWe report here a combined anti-cancer therapy directed toward HER2 and EpCAM, common tumor-associated antigens of breast cancer cells. The combined therapeutic effect is achieved owing to two highly toxic proteins-a low immunogenic variant of exotoxin A and ribonuclease Barnase from . The delivery of toxins to cancer cells was carried out by targeting designed ankyrin repeat proteins (DARPins).
View Article and Find Full Text PDFWhen combined with immunotherapy, image-guided targeted delivery of chemotherapeutic agents is a promising direction for combination cancer theranostics, but this approach has so far produced only limited success due to a lack of molecular targets on the cell surface and low therapeutic index of conventional chemotherapy drugs. Here, we demonstrate a synergistic strategy of combination immuno/chemotherapy in conditions of dual regioselective targeting, implying vectoring of two distinct binding sites of a single oncomarker (here, HER2) with theranostic compounds having a different mechanism of action. We use: (i) PLGA nanoformulation, loaded with an imaging diagnostic fluorescent dye (Nile Red) and a chemotherapeutic drug (doxorubicin), and functionalized with affibody Z (8 kDa); (ii) bifunctional genetically engineered DARP-LoPE (42 kDa) immunotoxin comprising of a low-immunogenic modification of therapeutic exotoxin A (LoPE) and a scaffold targeting protein, DARPin9.
View Article and Find Full Text PDFA novel 47-residue plant defensin was purified from germinated seeds of the lentil Lens culinaris by ammonium sulfate precipitation, gel filtration, chromatography, and RP-HPLC. The molecular mass (5440.41Da) and complete amino acid sequence (KTCENLSDSFKGPCIPDGNCNKHCKEKEHLLSGRCRDDFRCWCTRNC) of defensin, termed Lc-def, were determined.
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