Uptake Studies Research Articles

Non-invasive imaging with ICOS-targeting monoclonal antibody for preclinical diagnosis of rheumatoid arthritis in a humanized mouse model

BackgroundActivated T cells play a pivotal role in rheumatoid arthritis (RA) pathogenesis, and imaging of activated T cells may provide a non-invasive tool for RA detection. Here, we first developed an optical probe targeting human inducible T cell co-stimulator (ICOS) and tested its capacity in RA diagnosis by capturing ICOS+ activated T cells in vivo in a humanized mouse model.MethodsThe humanized arthritis model, Human peripheral blood mononuclear cells- adjuvant induced arthritis (HuPBMC-AIA) was established, and flow cytometry and immunofluorescence were employed to determine ICOS expression in huPBMC-AIA model. Anti-human ICOS monoclonal antibody (mAb) was conjugated to Cy7 via NHS ester amine reaction. A cell uptake study was used to confirm the specificity of Cy7-ICOS mAb to activated T cells. 4-view near-infrared fluorescence (NIRF) imaging study was performed to test Cy7-ICOS mAb in detecting RA in vivo.FindingsICOS was confirmed as an indicator of RA pathogenesis via RNA-seq, flow cytometry and immunofluorescence data. An in-vitro cellular uptake study validated the specificity of Cy7-ICOS mAb to activated T cells. Cy7-ICOS mAb could detect ICOS+ activated T cells in vivo through 4-view NIRF imaging. The receiver operating characteristic (ROC) curve created based on NIRF imaging quantification could distinguish the huPBMC-AIA group from the control group at all time points imaged.ConclusionIn this study, we first developed an optical imaging probe targeting human ICOS, Cy7-ICOS mAb. The 4-view NIRF imaging with Cy7-ICOS mAb could detect pathogenic ICOS+ activated T cells with high sensitivity and specificity in vivo, which indicated the great potential of this imaging probe in RA early diagnosis.

Holistic Investigation of Graphene Quantum Dot Endocytosis.

Graphene quantum dots (GQDs) have gained popularity in nano-biotechnology due to their multifunctional delivery and imaging capabilities. The outcome of their therapeutic delivery applications relies on understanding cell internalization routes. Current literature presents often conflicting results based on surveying only a few endocytosis inhibitors. Herein, a holistic approach to cell uptake studies by utilizing six different inhibitors while considering their on- and off-target effects on internalization of the GQDs of different charges is provided. Endocytosis paths are explored by tracking intracellular GQD fluorescence in HeLa or HEK-293 cells. Contrary to the previous assumptions of a singular entry route, findings suggest that GQDs enter the cells through several endocytosis paths with some more prevalent than others. Selectivity between the pathways is based on GQD charge and functional groups. Positively charged nitrogen-doped GQDs (NGQDs) predominantly utilize a fast endophilin-mediated endocytosis (FEME) in HeLa cells with a secondary preference for clathrin-mediated endocytosis (CME). In HEK-293 cells NGQDs internalize via clathrin-independent, glycosylphosphatidylinositol-anchored protein-enriched compartments (CLIC/GEEC) and FEME. Conversely, GQDs with a substantial negative surface charge uptake through CME in HeLa cells. The optimization of these mechanisms can enhance GQD applications in biomedicine, ideally streamlining their translation into the clinic.

Pre-clinical development of an enzyme replacement therapy for CLN1 Batten disease: Process development, stability and uptake studies

Pre-clinical development of an enzyme replacement therapy for CLN1 Batten disease: Process development, stability and uptake studies

Precise intracellular uptake and endosomal release of diverse functional mRNA payloads via glutathione-responsive nanogels.

We present a novel, highly customizable glutathione-responsive nanogel (NG) platform for efficient mRNA delivery with precise mRNA payload release control. Optimization of various cationic monomers, including newly synthesized cationic polyarginine, polyhistidine, and acrylated guanidine monomers, allowed fine-tuning of NG properties for mRNA binding. By incorporating a poly(ethylene) glycol-based disulphide crosslinker, we achieved glutathione-triggered mRNA release, enabling targeted intracellular delivery. Our NGs demonstrated superior encapsulation (up to 89.3%) and loading (10.7%) efficiencies, with controlled mRNA release kinetics at intracellular glutathione concentrations. NGs outperformed commercial transfection reagents across multiple cell lines, including traditionally difficult-to-transfect lines. We demonstrate the platform's versatility by successfully delivering GFP mRNA, Mango II RNA aptamers, and functionally relevant β2-AMPK mRNA. Furthermore, we used TIRF microscopy to measure exact RNA copy number within the NGs. Notably, mechanistic cellular uptake studies revealed that disulphide-containing NGs exhibit enhanced cellular uptake and endosomal escape, potentially due to interactions with cell surface thiols. This work represents a highly tuneable, efficient, and biocompatible platform for mRNA delivery with relevance for gene therapy and vaccine development.

Folate conjugated Nano-Lipid construct of Paclitaxel for site-specific lung squamous carcinoma targeting.

The objective of this study was to evaluate the effectiveness of folate-conjugated nano-lipid constructs (F-NLCs) for targeting lung squamous carcinoma through both ex-vivo and in-vivo studies. Ligand-conjugated (F-NLCs) and non-conjugated (P-NLCs) formulations were prepared using the solvent evaporation method, with paclitaxel as the reference drug. The formulations were characterized for particle size, zeta potential, encapsulation efficiency, and drug loading capacity. The average particle size of P-NLCs and F-NLCs was found to be 190.1 ± 1.9 nm and 231.3 ± 2.3 nm, respectively. The percent entrapment efficiency of P-NLCs and F-NLCs was 85.14 ± 1.4 % and 82.42 ± 1.2 %, respectively. The drug loading for P-NLCs and F-NLCs was 25.3 ± 1.1 % and 24.2 ± 1.3 %, respectively. The haemolytic study revealed lower toxicity for F-NLCs (4.36 ± 0.6 %) compared to P-NLCs (12.36 ± 0.8 %) and paclitaxel (25.41 ± 0.4 %). Ex-vivo studies, employing the SRB method, demonstrated GI50 (µM) values of 9.72 for P-NLCs and 5.84 for F-NLCs, compared to 18.51 for the paclitaxel solution. Cellular uptake studies using Rhodamine-B dye-loaded NLCs (F-D-NLCs), observed through fluorescence microscopy, indicated higher accumulation in the lung sac compared to D-NLCs. In vivo research, focusing on biodistribution and pharmacokinetics, was conducted on Wistar rats to confirm the efficacy of F-NLCs. Biodistribution results showed concentrations of 25.86 ± 0.39 % for F-NLCs and 3.14 ± 0.46 % for the paclitaxel solution in lung squamous carcinoma cells, indicating a significant improvement in drug concentration within carcinogenic squamous cells with F-NLCs. The findings conclude that F-NLCs are a safe, stable, and promising drug delivery system for the targeted treatment of lung squamous carcinoma.

Characterization of Buccal Mucosa as Barrier for Drug Absorption; A Mechanistic Study via Solvent Uptake and Model Drug Permeation Studies

Characterization of Buccal Mucosa as Barrier for Drug Absorption; A Mechanistic Study via Solvent Uptake and Model Drug Permeation Studies

Development, Characterization, and Evaluation of Chi-Tn mAb-Functionalized DOTAP-PLGA Hybrid Nanoparticles Loaded with Docetaxel for Lung Cancer Therapy

Background/Objectives: The focus of this study was to prepare and characterize docetaxel (DCX)-loaded lipid/polymer hybrid nanoparticles (LPHNps) functionalized with the monoclonal antibody (mAb) Chi-Tn for a potential active targeting approach in lung cancer treatment. Methods: We synthesized DOTAP-PLGA hybrid nanoparticles loaded with DCX and functionalized them with Chi-Tn mAb through a biotin–avidin approach. The physicochemical characterization involved dynamic light scattering, transmission electron microscopy, Raman spectroscopy, and atomic force microscopy. The in vitro and in vivo evaluations encompassed uptake studies, cell viability tests, and the assessment of tumor growth control in a lung cancer model. Results: The nanoparticles featured a hydrophobic PLGA core with 99.9% DCX encapsulation efficiency, surrounded by a DOTAP lipid shell ensuring colloidal stability with a high positive surface charge. The incorporation of PEGylated lipids on their surface helps evade the immune system and facilitate Chi-Tn mAb attachment. The resulting nanoparticles exhibit a spherical shape with monodisperse particle sizes averaging 250 nm, and demonstrate sustained drug release. In vitro uptake studies and viability assays conducted in A549 cancer cells show that the Chi-Tn mAb enhances nanoparticle internalization and significantly reduces cell viability. In vivo studies demonstrate a notable reduction in tumor volume and an increased survival rate in the A549 tumor xenograft mice model when DCX was encapsulated in nanoparticles and targeted with Chi-Tn mAb in comparison to the free drug. Conclusions: Therefore, Chi-Tn-functionalized LPHNps hold promise as carriers for actively targeting DCX to Tn-expressing carcinomas.

Ex Vivo Biosafety and Efficacy Assessment of Advanced Chlorin e6 Nanoemulsions as a Drug Delivery System for Photodynamic Antitumoral Application

The photosensitizer (PS) in the Photodynamic Therapy (PDT) field represents a key factor, being directly connected to the therapeutic efficacy of the process. Chlorin e6 is a second-generation photosensitizer, approved by the FDA with the most desired clinical properties for PDT applications, presenting high reactive oxygen species (ROS) generation and proven anticancer properties. However, hydrophobicity is a major limitation, leading to poor biodistribution. To overcome this condition, the present work developed an up-to-date nanoemulsion incorporating Ce6 in a new nanosystem (Ce6/NE). A comprehensive study of physicochemical properties, stability, fluorescence characteristics, the in vitro release profile, in vivo and ex vivo biocompatibility, and ex vivo efficacy was established. The nanoemulsions showed the desired particle size and stability over six months, with no spectroscopic or photophysical alterations. Uptake studies demonstrated the internalization of the Ce6/NE in monolayers, with biocompatibility at the lowest concentrations. The HET-CAM assay, however, revealed a higher biocompatibility range, also indicating Ce6/NE’s potential for cancer treatment through antiangiogenic studies. These findings highlight the use of a new promising photosensitizer for PDT modulated with nanotechnology that promotes low toxicity, higher bioavailability, and site-specific delivery.

In situ forming gels as subcutaneous delivery systems of curcumin and piperine

In this study an in situ forming gel for curcumin and piperine delivery is investigated as a long-lasting strategy in the local treatment of inflammatory and degenerative joint disease, such as osteoarthritis and rheumatoid arthritis. Particularly glyceryl monooleate, in association with phosphatidylcholine and ethanol, were employed. Different ratios between excipients were tested, with the aim to obtain a liquid form suitable for subcutaneous injection, gaining a semisolid consistency in contact with biological fluids. A formulative study was conducted to assess the composition impact on the structural properties of the formulations, particularly focusing on injectability and phase transition. Curcumin and piperine were loaded, singularly or jointly, in selected in situ forming gels. Structural characterization, performed by X-ray scattering, revealed disordered reverse micellar phases, undergoing transition to hexagonal and cubic Pn3m phase upon hydration. In vitro dialysis release study demonstrated a sustained release of both drugs over 96 h, with a faster release in the case of jointly loaded drugs. Mechanistic analysis and water uptake studies indicated a drug release governed by both diffusion and swelling/erosion of the lipid supramolecular structure. Furthermore, an ex vivo release analysis performed using human skin explants suggested the formulation suitability for subcutaneous injection, indicating that the presence of piperine in the in situ formed gel allowed to double the curcumin release with respect to the simple curcumin loaded gel.

True cancer stem cells exhibit relative degrees of dormancy and genomic stability.

Cancer stem cells in human tumors have been defined by stem cell markers, embryonal signaling pathways and characteristic biology, ie., namely the ability to repopulate the proliferating population. However, even if these properties can be demonstrated within a tumor cell subpopulation, it does not mean that they are truly hierarchical stem cells because they could have been derived from the proliferating population in a reversible manner. Using a human PDX, Mary-X, that overall expressed a strong cancer stem cell phenotype, the study conducted both GPP-labelled retroviral transfection and fluorescent microsphere uptake studies to distinguish proliferating from dormant cells and array CGH to identify regions of amplifications (gains) and deletions (losses) on the overall Mary-X population and then applied derived probes by FISH on individual cells to identify a genomically stable subpopulation. Whereas 97-99 % of the cells expressed retroviral GFP and not fluorescent particles and showed numerous gene amplifications and deletions, approximately 1-3 % of the cells showed the opposite. The subpopulation with the retained fluorescent microspheres and exhibiting genomic stability was significantly smaller in size than their GFP-expressing and genomically unstable counterparts. Sorting Mary-X spheroids on the basis of either CD133 or ALDH positivity further enriched for this subpopulation. These studies indicate that a truly biological cancer stem cell subpopulation exists that exhibits both dormancy and genomic stability. This subpopulation could not have been derived from the proliferating and resulting genomically unstable population and therefore represents a truly hierarchical stem cell subpopulation capable of only unidirectional differentiation.

Development of a phosphoaminopyrazine-loaded cellulose nanoparticle drug delivery system for targeted treatment of triple-negative breast cancer.

This study explores the development of a sustainable drug delivery system using cellulose nanoparticles (CNPs) derived from potato pulp for the controlled release of phosphoaminopyrazine (PAP), a promising anticancer agent. CNPs were synthesized via nanoprecipitation, and PAP was loaded through in-situ nanoprecipitation, achieving a high loading efficiency of 79.2 %. Characterization of CNPs and PAP-loaded CNPs (PAP@CNP) using Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and thermogravimetric analysis (TGA) confirmed the structural integrity, spherical morphology (45.33 nm for CNPs, 54.6 nm for PAP@CNP), and enhanced thermal stability of PAP@CNP. In vitro, drug release studies demonstrated sustained release over 48 h, with pH-sensitive kinetics favoring the acidic tumor microenvironment. Cytotoxicity assays revealed superior efficacy of PAP@CNP against triple-negative breast cancer cells (MDA-MB-231; IC50 = 20.86 ± 0.81 μg/mL) compared to cisplatin while showing minimal toxicity to normal human umbilical vein endothelial cells (HUVECs). Cellular uptake studies using epifluorescence microscopy and flow cytometry confirmed time-dependent internalization and intracellular drug release. Potato pulp, an abundant agro-industrial waste, as a renewable source for CNPs highlights this approach's economic and environmental advantages. This study demonstrates the potential of potato pulp-derived CNPs as a sustainable and cost-effective platform for targeted cancer therapy; offering improved therapeutic outcomes and reduced environmental impact.

Two stages of substrate discrimination dictate selectivity in the E. coli MetNI-Q ABC transporter system.

The Escherichia coli MetNI-Q importer, an ATP-binding cassette (ABC) transporter, mediates the uptake of both L- and D-enantiomers of methionine. Original in vivo uptake studies show a strong preference for L-Met over D-Met, but the molecular basis of this selectivity is unclear. In this work, we systematically examine substrate discrimination by the MetNI transporter and MetQ substrate binding protein using an array of biophysical and biochemical techniques. Based on the kinetic and thermodynamic parameters of individual intermediates in the transport cycle, we uncover multiple steps in the transport cycle that confer substrate specificity. As in many other ABC importer systems, selectivity is applied at the level of binding to the substrate binding protein: MetQ dictates a 1,000-fold preference for L-Met over D-Met. However, beyond this initial level of selectivity, MetQ displays distinct binding preferences for the MetNI transporter depending on the substrate. We propose that the differences in binding affinities reflect the more favored release of L-Met into the permeation pathway when compared to D-Met. In support of this model, under saturating conditions, MetNI transports L-Met across the lipid bilayer at a faster rate than D-Met. Interestingly, the ATPase activity of the MetNI-Q complex is not modulated by the presence of substrate. Our studies reveal that the MetNI-Q system incorporates two separate steps in tuning methionine uptake to substrate chirality and availability. This method of discrimination ensures the import of the most biologically preferred substrate while also allowing for adaptability to more limiting nutrient conditions.

N-acetylcysteine and chitosan conjugate modified dexamethasone nanostructured lipid carriers: Enhanced permeability, precorneal retention and lower inflammation for the treatment of dry eye syndrome.

Dexamethasone (Dex) is a primary medication for treating dry eye syndrome, and tobramycin-dexamethasone eye drops are commercially available. However, the eye's complex physiological environment reduces its bioavailability, and repeated use can lead to significant systemic toxicity and side effects. This study introduces a novel conjugate of chitosan (CS) and N-acetylcysteine (NAC), a bioadhesive material, which was grafted onto the surface of a Dex-supported nanostructured lipid carrier (NLC) to develop an innovative nanoparticle lipid ocular drug delivery system (CS-NAC@Dex-NLC). The enhancements afforded by CS-NAC, such as adhesion, osmotic, and targeting properties, address the limitations of traditional eye drops. NMR characterization confirmed the successful synthesis of the copolymer (CS-NAC). Particle size (PS), zeta potential, and transmission electron microscopy (TEM) verified the proper formation of the CS-NAC@Dex-NLC system. Cytotoxicity tests confirmed its excellent biocompatibility and safety. Cellular uptake studies showed that CS-NAC@Dex-NLC achieved the highest efficiency. Pharmacokinetic assessments revealed a significant increase in Dex's bioavailability in tears and aqueous humor. In vitro corneal penetration and in vivo imaging experiments demonstrated effective corneal penetration and retention, enhancing the drug's duration on the ocular surface and overcoming the barrier effect. Pharmacodynamic studies in rabbits with dry eye syndrome indicated that CS-NAC@Dex-NLC effectively alleviates symptoms, repairs corneal damage, and stabilizes the tear film. ELISA results showed a reduction in inflammation caused by dry eye. These findings suggest that CS-NAC@Dex-NLC is a promising vector for dry eye treatment, offering significant clinical relevance.

Multidimensional Demographic Analyses of COVID-19 Vaccine Inequality in the United States: A Systematic Review.

COVID-19 vaccination uptake is associated with demographic characteristics such as age, sex, and ethnicity-race in the United States (U.S.). Prior research predominantly analyzed COVID-19 vaccination uptake unidimensionally, limiting insights into multidimensional demographic inequalities. Multidimensional studies provide a closer insight into vaccination inequality and assist in designing more effective vaccination strategies. Review descriptive studies of the COVID-19 vaccination uptake across combinations of at least two of the three key demographic characteristics: age, sex, and ethnicity-race in the U.S. A systematic review was performed using the Joanna Briggs Institute methodology and adhering to the PRISMA-ScR principles for reporting. Six impartial reviewers examined all of the papers. The data were obtained using a tailored data extraction template. A total of 2793 records were initially downloaded, 461 of them were dropped for duplication, and 2332 were reviewed. Based on the title and abstract reviews, 2115 records were excluded. After reviewing the full text of the remaining records, 212 more records were excluded. The remaining six records were reviewed to identify and compare their population, study period, data, the studied dose number, methodology, and results. Multidimensional COVID-19 vaccine uptake analyses are rare and mostly focused on the dose-one vaccination. Improving researchers' access to immunization registry data while preserving data security is a prerequisite for such analyses.

99mTc]Technetium and Rhenium Dithiocarbazate Complexes: Chemical Synthesis and Biological Assessment.

Dithiocarbazates (DTCs) and their metal complexes have been studied regarding their property as anticancer activities. In this work, using S-benzyl-5-hydroxy-3-methyl-5-phenyl-4,5-dihydro-1H-pirazol-1-carbodithionate (H2bdtc), we prepared [ReO(bdtc)(Hbdtc)] and [[99mTc]TcO(bdtc)(Hbdtc)] complexes for tumor uptake and animal biodistribution studies. Re complex was prepared by a reaction of H2bdtc and (NBu4)[ReOCl4], the final product was characterized by IR, 1H NMR, CHN, and MS-ESI. 99mTc complex was prepared by the reaction of H2bdtc and [[99mTc]TcO4- and analyzed by planar and HPLC radiochromatography, and the stability was evaluated against amino acids and plasma. Biodistribution was performed in C57B/6 mice with B16F10 and TM1M implanted tumor. Re is asymmetric coordinated by two dithiocarbazate ligands, one with O,N,S chelation, and the other with N,S chelation; [[99mTc]TcO(bdtc)(Hbdtc)] was prepared with a radiochemical yield of around 93%. The radioactive complex is hydrophobic (LogP = 1.03), stable for 6 h in PBS and L-histidine solution; stable for 1 h in plasma, but unstable in the presence of L-cysteine. Ex vivo biodistribution demonstrated that the compound has a fast and persistent (until 2 h) uptake by the spleen (55.46%), and tumor B16F10 and TM1M uptake is lower than 1%. In vivo SPECT/CT imaging confirmed ex vivo biodistribution, except by heterogenous TM1M accumulation but not in the B16-F10 lineage. H2bdtc proved to be an interesting chelator for rhenium or [99mTc]technetium. The right spleen uptake opened the opportunity to deepen the study of the molecule in this tissue and justifies future studies to identify the reason of heterogenous uptake in TM1M tumor uptake.

Scalable Manufacturing Method for Model Protein-Loaded PLGA Nanoparticles: Biocompatibility, Trafficking and Release Properties.

Background and Objectives: Drug delivery systems (DDSs) offer efficient treatment solutions to challenging diseases such as central nervous system (CNS) diseases by bypassing biological barriers such as the blood-brain barrier (BBB). Among DDSs, polymeric nanoparticles (NPs), particularly poly(lactic-co-glycolic acid) (PLGA) NPs, hold an outstanding position due to their biocompatible and biodegradable qualities. Despite their potential, the translation of PLGA NPs from laboratory-scale production to clinical applications remains a significant challenge. This study aims to address these limitations by developing scalable PLGA NPs and evaluating their potential biological applications. Methods: We prepared blank and model-protein-loaded (albumin-FITC and wheat germ agglutinin-488 (WGA-488)) fluorescent PLGA NPs using the traditional double-emulsion method combined with the micro-spray-reactor system, a novel approach that enables fine particle production enabling scale-up applications. We tested the biocompatibility of the NPs in living RPMI 2650 and neuroblastoma cell lines, as well as their trafficking and uptake. Release kinetics of the encapsulated proteins were investigated through confocal microscopy and in vitro release studies, providing insights into the stability and functionality of the released proteins. Results: The formulation demonstrated sustained and prolonged protein release profiles. Importantly, cellular uptake studies revealed that the NPs were not internalized. Furthermore, encapsulated WGA-488 protein retained its functional activity after release, validating the integrity of the encapsulation and release processes. Conclusions: The proof-of-concept study on NP manufacturing and an innovative drug trafficking and release approach can bring new perspectives on scalable preparations of PLGA NPs and their biological applications.

Modulation of Donor in Purely Organic Triplet Harvesting AIE-TADF Photosensitizer for Image-guided Photodynamic Therapy.

Image-guided photodynamic therapy is acknowledged as one of the most demonstrative therapeutic modalities for cancer treatment because of its high precision, non-invasiveness, and improved imaging ability. A series of purely organic photosensitizers denoted as BTMCz, BTMPTZ, and BTMPXZ, have been designed and synthesized and are found to exhibit both thermally activated delayed fluorescence and aggregation-induced emission simultaneously. Experimental and theoretical studies are combined to reveal that modulation of the donor of the photosensitizer enables distinct thermally activated delayed fluorescence via a second-order spin-orbit perturbation mechanism involving lowest singlet charge-transfer and higher-lying triplet locally excited states, respectively. Further, different donor strengths and unique aggregations (H-, J- and X-type packings) greatly influence their color-tunable up-converted luminescence and endow them with superb dispersibility in water. The confocal microscopy-based cellular uptake study confirms the successful internalization of the nano-probes, while BTMCz enables the generation of reactive oxygen species (singlet oxygen) under white-light irradiation, enabling the efficient killing of cancer cells.

SSTR2-Targeted Theranostics in Hepatocellular Carcinoma.

While the clinical use of radiolabeled somatostatin analogs is well established in neuroendocrine tumors, there is growing interest in expanding their application to other somatostatin receptor 2 (SSTR2)-expressing cancers. This study investigates the potential utility of SSTR2-targeted theranostics in hepatocellular carcinoma (HCC). SSTR2 expression in HCC cell lines and clinical samples was evaluated using qRT-PCR, Western blot analysis, and a public dataset. 67Ga-DOTATATE uptake was measured, 177Lu-DOTATATE cytotoxicity was assessed, and 68Ga-DOTATATE tumor targeting was evaluated in HCC animal models and a patient via PET/CT imaging. SSTR2 expression was confirmed in HCC cell lines and clinical samples. Radioligand uptake studies demonstrated SSTR2-mediated 67Ga-DOTATATE uptake. 177Lu-DOTATATE treatment reduced cell proliferation and enhanced the anti-tumor efficacy of the multikinase inhibitor sorafenib. 68Ga-DOTATATE PET/CT scans successfully identified tumors in HCC animal models and spinal metastases in a patient with HCC. These findings provide evidence that SSTR2-based theranostics could have significant implications for the detection and treatment of HCC.

Impact of the hydrophilic-lipophilic balance of free-base and Zn(II) tricationic pyridiniumporphyrins and irradiation wavelength in PDT against the melanoma cell lines.

The amphiphilic and asymmetric structure of porphyrins, when used as photosensitizers (PSs) for photodynamic therapy (PDT), has been shown through numerous previous studies to be a very important property that facilitates their entry into cells, which improves their efficiency in PDT. In this work, two groups of cationic AB3 pyridiniumporphyrins, free-base and chelated with Zn(II), both substituted with alkyl chains of various lengths, were studied in PDT on melanoma cell lines. The aim was to investigate the impact of hydrophilic-lipophilic balance and Zn(II) chelation, and the importance of matching the irradiation wavelength to the optical properties of the PS on in vitro PDT efficiency. Therefore, spectroscopic studies, singlet oxygen production and lipophilicity as well as cellular uptake, localization and cytotoxicity studies of the two series of porphyrins were performed. In both series of porphyrins, the longest alkyl chain (17C-atoms long) enables the greatest internalization of the PS. Chelation with Zn(II) resulted in better physicochemical properties, but slower cellular internalization. As expected, free-base porphyrins were more PDT efficient than their Zn(II) complexes after 30-min photoactivation by low-fluence (2mW/cm2) red light (643nm). However the use of orange light (606nm) with the same fluence rate was more suitable for Zn(II) porphyrins and resulted in similar overall toxicity to their free-base analogues with similar lipophilicity. Although the highest phototoxicity was achieved with the PSs carrying the longest alkyl chain, TMPyP3-C13H27 and Zn(II)-TMPyP3-C13H27 proved to be the most promising candidates for use in PDT as they exhibit high phototoxicity, but also greater selectivity towards melanoma cell lines (MeWo and A375) compared to fibroblasts (HDF).

PEGylated solid lipid nanoparticles for the intranasal delivery of combination antiretroviral therapy composed of Atazanavir and Elvitegravir to treat NeuroAIDS.

Intranasal drug administration offers a promising strategy for delivering combination antiretroviral therapy (cART) directly to the central nervous system to treat NeuroAIDS, leveraging the nose-to-brain route to bypass the blood-brain barrier. However, challenges such as enzymatic degradation in the nasal mucosa, low permeability, and mucociliary clearance within the nasal cavity must first be addressed to make this route feasible. To overcome these barriers, this study developed solid lipid nanoparticles (SLNs) with varying PEGylation levels (0%, 5%, 10%, and 15% w/w of PEGylated lipid), co-encapsulated with Elvitegravir (EVG) and Atazanavir (ATZ) as an integrase and protease inhibitor, respectively. Pre-formulation studies confirmed the compatibility of the drugs with the excipients. Characterization showed that PEGylation reduces SLN size by approximately up to 12% while maintaining monodispersity and a high encapsulation efficiency of over 99% for both EVG and ATZ in their amorphous forms. Incubation of the formulations in artificial nasal mucus revealed that increased PEGylation consistently reduces nanoparticle aggregation and mean aggregate size, suggesting improved SLN stability in the mucus. Importantly, higher PEGylation levels significantly enhanced model drug permeability across the nasal mucus barrier by up to 10-fold. Lastly, cellular uptake studies using the RPMI 2650 nasal epithelial cell line indicated that PEGylation does not reduce nanoparticle uptake rates. These findings highlight the potential of PEGylated SLNs as an effective vehicle for enhancing the intranasal delivery of cART to treat NeuroAIDS. However, further in vivo studies are needed to confirm the brain targeting potential of this formulation.