• Buck Ortiz posted an update 5 hours, 36 minutes ago

    Poly[lactic-co-(glycolic acid)] (PLGA) is arguably one of the most versatile synthetic copolymers used for biomedical applications. In vivo delivery of multiple substances including cells, pharmaceutical compounds, and antigens has been achieved by using PLGA-based micro-/nanoparticles although, presently, the exact biological impact of PLGA particles on the immune system remains controversial. Type 1 diabetes (T1D) is one subtype of diabetes characterized by the attack of immune cells against self-insulin-producing pancreatic islet cells. Considering the autoimmune etiology of T1D and the recent use of PLGA particles for eliciting desired immune responses in various aspects of immunotherapy, for the present study, a combination of Ins29-23 peptide (a known autoantigen of T1D) and PLGA microparticles was selected for T1D prevention assessment in nonobese diabetic (NOD) mice, a well-known animal model with spontaneous development of T1D. Thus, inoculation of PLGA microparticles + Ins29-23 completely prevented T1D development, significantly better than untreated controls and mice treated by either PLGA microparticles or Ins29-23 per se. Subsequent mechanistic investigation further revealed a facilitative role of PLGA microparticles in immune tolerance induction. In summary, our data demonstrate an adjuvant potential of PLGA microparticles in tolerance induction and immune remodulation for effective prevention of autoimmune diseases such as T1D.Active immunization is an emerging potential modality to combat fatal overdose amid the opioid epidemic. In this study, we described the design, synthesis, formulation, and animal testing of an efficacious vaccine against fentanyl. The vaccine formulation is composed of a novel fentanyl hapten conjugated to tetanus toxoid (TT) and adjuvanted with liposomes containing monophosphoryl lipid A adsorbed on aluminum hydroxide. The linker and hapten N-phenyl-N-(1-(4-(3-(tritylthio)propanamido)phenethyl)piperidin-4-yl)propionamide were conjugated sequentially to TT using amine-N-hydroxysuccinimide-ester and thiol-maleimide reaction chemistries, respectively. Conjugation was facile, efficient, and reproducible with a protein recovery of >98% and a hapten density of 30-35 per carrier protein molecule. In mice, immunization induced high and robust antibody endpoint titers in the order of >106 against the hapten. The antisera bound fentanyl, carfentanil, cyclopropyl fentanyl, para-fluorofentanyl, and furanyl fentanyl in vitro with antibody-drug dissociation constants in the range of 0.36-4.66 nM. No cross-reactivity to naloxone, naltrexone, methadone, or buprenorphine was observed. In vivo, immunization shifted the antinociceptive dose-response curve of fentanyl to higher doses. Collectively, these preclinical results showcased the desired traits of a potential vaccine against fentanyl and demonstrated the feasibility of immunization to combat fentanyl-induced effects.Molecular miscibility and homogeneity of amorphous solid dispersions (ASDs) are critical attributes that impact physicochemical stability, bioavailability, and processability. Observation of a single glass transition is utilized as a criterion for good mixing of drug substance and polymeric components but can be misleading and cannot quantitatively analyze the domain size at high resolution. While imaging techniques, on the other hand, can characterize phase separation on the particle surface at the nanometer scale, they often require customized sample preparation and handling. Moreover, a mixed system is not necessarily homogeneous. GBD9 Compared to the numerous studies that have evaluated the mixing of drug substance and polymer in ASDs, inhomogeneity in the phase compositions has remained significantly underexplored. To overcome the analytical challenge, we have developed a 1H spin diffusion NMR technique to quantify molecular mixing of bulk ASDs at sub-100 nm resolution. It combines relaxation filtering (T2H a scale observed in atomic force microscopy (AFM) images. The incomplete equilibration and differential relaxation were consistently reproduced in a model of two mixed phases of different compositions, e.g., 40 wt % of the ASD with a 15 wt % drug loading and the remaining 60 wt % with a 56 wt % drug loading. Hot-melt extrusion produced more inhomogeneous samples than spray drying for the samples examined in our study. To the best of our knowledge, this spin diffusion NMR method provides currently the highest-resolution quantification of inhomogeneous molecular mixing and phase composition in bulk samples of pharmaceutical dispersions produced with equipment, procedures, and drug loadings that are relevant to industrial drug development.Influenza viruses cause seasonal epidemics and represent a pandemic risk. With current vaccine methods struggling to protect populations against emerging strains, there is a demand for a next-generation flu vaccine capable of providing broad protection. Recombinant biotechnology, combined with nanomedicine techniques, could address this demand by increasing immunogenicity and directing immune responses toward conserved antigenic targets on the virus. Various nanoparticle candidates have been tested for use in vaccines, including virus-like particles, protein and carbohydrate nanoconstructs, antigen-carrying lipid particles, and synthetic and inorganic particles modified for antigen presentation. These methods have yielded some promising results, including protection in animal models against antigenically distinct influenza strains, production of antibodies with broad reactivity, and activation of potent T cell responses. Based on the evidence of current research, it is feasible that the next generation of influenza vaccines will combine recombinant antigens with nanoparticle carriers.Efficient delivery of oral drugs is dependent on their solubility in human intestinal fluid, a complex and dynamic fluid that contains colloidal structures composed of small molecules. These structures solubilize poorly water-soluble compounds, increasing their apparent solubility, and possibly their bioavailability. In this study, we conducted coarse-grained molecular dynamics simulations with data from duodenal fluid samples previously acquired from five healthy volunteers. In these simulations, we observed the self-assembly of mixed micelles of bile salts, phospholipids, and free fatty acids. The micelles were ellipsoids with a size range of 4-7 nm. Next, we investigated micelle affinities of three model drugs. The affinities in our simulation showed the same trend as literature values for the solubility enhancement of drugs in human intestinal fluids. This type of simulations is useful for studies of events and interactions taking place in the small intestinal fluid.