Lymph node macrophages drive innate immune responses to enhance the anti-tumor efficacy of mRNA vaccines.

mRNA vaccines are promising for cancer treatment. Efficient delivery of mRNAs encoding tumor antigens to antigen-presenting cells (APCs) is critical to elicit anti-tumor immunity. Herein, we identified a novel lipid nanoparticle (LNP) formulation, L17-F05, for mRNA vaccines by screening 34 ionizable lipids and 28 LNP formulations using human primary APCs. Subcutaneous delivery of L17-F05 mRNA vaccine encoding Gp100 and Trp2 inhibited tumor growth and prolonged the survival of mice bearing B16F10 melanoma. L17-F05 efficiently delivered mRNAs to conventional dendritic cells (cDCs) and macrophages in draining lymph nodes (dLNs). cDCs functioned as the main APCs by presenting antigens along with enhanced expression of co-stimulatory molecules. Macrophages triggered innate immune responses centered on type-I interferon (IFN-I) in dLNs. Lymph node (LN) macrophage depletion attenuated APC maturation and anti-tumor activity of L17-F05 mRNA vaccines. Loss-of-function studies revealed that L17-F05 works as a self-adjuvant by activating the stimulator of interferon genes (STING) pathway in macrophages. Collectively, the self-adjuvanticity of L17-F05 triggered innate immune responses in LN macrophages via the STING-IFN-I pathway, contributing to APC maturation and potent anti-tumor activity of L17-F05 mRNA vaccines. Our findings provide strategies for further optimization of mRNA vaccines based on the innate immune response driven by LN macrophages.

Understanding the Manufacturing Process of Lipid Nanoparticles for mRNA Delivery Using Machine Learning.

Lipid nanoparticles (LNPs), used for mRNA vaccines against severe acute respiratory syndrome coronavirus 2, protect mRNA and deliver it into cells, making them an essential delivery technology for RNA medicine. The LNPs manufacturing process consists of two steps, the upstream process of preparing LNPs and the downstream process of removing ethyl alcohol (EtOH) and exchanging buffers. Generally, a microfluidic device is used in the upstream process, and a dialysis membrane is used in the downstream process. However, there are many parameters in the upstream and downstream processes, and it is difficult to determine the effects of variations in the manufacturing parameters on the quality of the LNPs and establish a manufacturing process to obtain high-quality LNPs. This study focused on manufacturing mRNA-LNPs using a microfluidic device. Extreme gradient boosting (XGBoost), which is a machine learning technique, identified EtOH concentration (flow rate ratio), buffer pH, and total flow rate as the process parameters that significantly affected the particle size and encapsulation efficiency. Based on these results, we derived the manufacturing conditions for different particle sizes (approximately 80 and 200 nm) of LNPs using Bayesian optimization. In addition, the particle size of the LNPs significantly affected the protein expression level of mRNA in cells. The findings of this study are expected to provide useful information that will enable the rapid and efficient development of mRNA-LNPs manufacturing processes using microfluidic devices.

Analysis of disease model iPSCs derived from patients with a novel Fanconi anemia-like IBMFS ADH5/ALDH2 deficiency.

We have recently discovered Japanese children with a novel Fanconi anemia-like inherited bone marrow failure syndrome (IBMFS). This disorder is likely caused by the loss of a catabolic system directed toward endogenous formaldehyde due to biallelic variants in ADH5 combined with a heterozygous ALDH2*2 dominant-negative allele (rs671), which is associated with alcohol-induced Asian flushing. Phytohemagglutinin-stimulated lymphocytes from these patients displayed highly increased numbers of spontaneous sister chromatid exchanges (SCEs), reflecting homologous recombination repair of formaldehyde damage. Here, we report that, in contrast, patient-derived fibroblasts showed normal levels of SCEs, suggesting that different cell types or conditions generate various amounts of formaldehyde. To obtain insights about endogenous formaldehyde production and how defects in ADH5/ALDH2 affect human hematopoiesis, we constructed disease model cell lines, including induced pluripotent stem cells (iPSCs). We found that ADH5 is the primary defense against formaldehyde, and ALDH2 provides a backup. DNA repair capacity in the ADH5/ALDH2-deficient cell lines can be overwhelmed by exogenous low-dose formaldehyde, as indicated by higher levels of DNA damage than in FANCD2-deficient cells. Although ADH5/ALDH2-deficient cell lines were healthy and showed stable growth, disease model iPSCs displayed drastically defective cell expansion when stimulated into hematopoietic differentiation in vitro, displaying increased levels of DNA damage. The expansion defect was partially reversed by treatment with a new small molecule termed C1, which is an agonist of ALDH2, thus identifying a potential therapeutic strategy for the patients. We propose that hematopoiesis or lymphocyte blastogenesis may entail formaldehyde generation that necessitates elimination by ADH5/ALDH2 enzymes.

Preparation of Fine-Drugs Layered Spherical Particles with Good Micromeritic and Dissolution Properties through Ultra Cryo-Milling and Mechanical Powder Processing.

The particles of phenytoin (Phe), a poorly water-soluble model drug, were bead-milled alone or co-milled with a hydrophilic waxy additive using an ultra cryo-milling technique in liquid nitrogen (LN2) to improve its dissolution properties. However, the micronized drug particles adhered and aggregated, resulting in poor handling in manufacturing processes such as blending or tableting. To improve the dissolution profile and powder properties of the drug simultaneously, the milled products were secondarily processed together with larger spherical particles by mechanical powder processing. These secondary products were composite particles with a core-shell structure, with fine drug particles adhered and deposited on the core, based on order mixing theory. As a core, three types/sizes of spherical pharmaceutical excipient particles were applied. The resultant composite particles produced much faster release profiles than just milled or co-milled mixtures. In addition, the composite particles showed good micromeritic properties depending on the size of the core particles. These results indicate that the ultra cryo-milling and subsequent dry composite mixing is a potential approach for developing drug particles with improved dissolution.

Ultra Cryo-Milling with Liquid Nitrogen and Dry Ice Beads: Characterization of Dry Ice as Milling Beads for Application to Various Drug Compounds.

Ultra cryo-milling using liquid nitrogen (LN2) and dry ice beads has been proposed as a contamination-free milling technique. The morphological change of dry ice beads was visually monitored in LN2 to clarify their production process and cryo-milling process. We found that dry ice pellets, which are starting material of beads and available on the market, immediately disintegrate in LN2, resulting in the spontaneous production of dry ice beads. In addition, the resultant beads maintain their size and shape even under vigorous agitation in LN2, demonstrating that they could play a role of milling media in the milling process. The driving conditions of this cryogenic milling process including beads size were optimized to enhance the milling efficiency. Dry ice beads provided superior milling efficiency compared to original pellets. The milling efficiency increased as the size of the dry ice beads decreased; furthermore, the larger the amount of beads used, the finer the milled particles. Any crystals of three drug compounds were effectively pulverized to the sub- or single-micron range. Cryo-milling with dry ice beads is valuable on pharmaceutical field because it does not contaminate the product with fractured and/or eroded beads.

Design of Highly Dispersible PLGA Microparticles in Aqueous Fluid for the Development of Long-Acting Release Injectables.

In this study, we developed highly dispersible polylactic glycolic acid (PLGA) copolymer microparticles (MRPs) in aqueous fluid. A solution containing both dissolved aripiprazole as a model drug and PLGA were spray-dried to make MRPs. The resultant MRPs were further co-processed with water-soluble additives and a surfactant to improve their dispersion behavior. The granules containing MRPs and additives, termed granulated microparticles (G-MRPs) were prepared by a newly established drop freeze-drying technique. The physicochemical properties of MRPs and G-MRPs were evaluated as a long-acting release depot injectable. The MRPs were spherical particles with diameters of approximately 1 to 20 µm and strongly assembled to one another in the aqueous phase, forming large aggregations. In contrast, the G-MRPs were spherical granules with diameters of approximately 200 to 400 µm that displayed a microparticles-in-granule structure in which small MRPs were embedded in the porous matrix inside the granules. When the G-MRPs were placed in water, the porous matrix base was immediately dissolved, and each embedded MRP was individually released, thus inducing monodispersion and significantly improved dispersibility. The excellent dispersibility was attributed to the water-soluble porous network structure mainly composed of D-mannitol and the steric hindrance effects derived from the polymeric molecular chains. These properties may give rise to the excellent passage of PLGA microparticles through needles for use in depot formulation suspensions. A crystalline evaluation of the G-MRPs suggested that the drug and PLGA molecularly interacted and that their thermodynamic stability was improved.

Greater Severity of Neurological Defects in Women Admitted With Atrial Fibrillation-Related Stroke.

BACKGROUND: The magnitude of the CHA2DS2-VASc score is associated with not only stroke incidence but also long-term outcomes. The association between sex and initial stroke severity in AF-related cardioembolic stroke patients has not been clarified. The present study aimed to elucidate the risk factors for initial stroke severity among patients with cardioembolic stroke enrolled in a multicenter registry. METHODS AND RESULTS: We selected 12,701 patients (age, 77±10 years; 5,653 women) with AF-related cardioembolic stroke from the Japan Standard Stroke Registry Study between January 2000 and July 2013. Indicators of National Institutes of Health Stroke Scale (NIHSS) scores at admission were identified using a multiple linear regression. Increased NIHSS scores positively correlated with CHA2DS2-VASc score (ρ=0.197; P<0.001). The initial neurological deficits were more severe in women than in men (NIHSS scores, median [interquartile range] 14 [5-22] vs. 8 [3-18]; P<0.001). Multiple regression analysis revealed that higher age (standardized partial regression coefficient [ß] 0.162; P<0.001), female sex (ß 0.120; P<0.001), diabetes mellitus (ß 0.020; P=0.019), dyslipidemia (ß -0.076; P<0.001), congestive heart failure (ß 0.039; P<0.001), vascular disease (ß 0.030; P=0.001), prior stroke/TIA (ß 0.085; P<0.001) and prior anticoagulant use (ß -0.020; P=0.028) were associated with the NIHSS score at admission. CONCLUSIONS: Female sex was independently associated with the initial neurological severity among AF-related cardioembolic stroke patients.

Development of a method for reconstruction of crowded NMR spectra from undersampled time-domain data.

NMR is a unique methodology for obtaining information about the conformational dynamics of proteins in heterogeneous biomolecular systems. In various NMR methods, such as transferred cross-saturation, relaxation dispersion, and paramagnetic relaxation enhancement experiments, fast determination of the signal intensity ratios in the NMR spectra with high accuracy is required for analyses of targets with low yields and stabilities. However, conventional methods for the reconstruction of spectra from undersampled time-domain data, such as linear prediction, spectroscopy with integration of frequency and time domain, and analysis of Fourier, and compressed sensing were not effective for the accurate determination of the signal intensity ratios of the crowded two-dimensional spectra of proteins. Here, we developed an NMR spectra reconstruction method, "conservation of experimental data in analysis of Fourier" (Co-ANAFOR), to reconstruct the crowded spectra from the undersampled time-domain data. The number of sampling points required for the transferred cross-saturation experiments between membrane proteins, photosystem I and cytochrome b 6 f, and their ligand, plastocyanin, with Co-ANAFOR was half of that needed for linear prediction, and the peak height reduction ratios of the spectra reconstructed from truncated time-domain data by Co-ANAFOR were more accurate than those reconstructed from non-uniformly sampled data by compressed sensing.

Elucidation of the CCR1- and CCR5-binding modes of MIP-1α by application of an NMR spectra reconstruction method to the transferred cross-saturation experiments.

C-C chemokine receptor 1 (CCR1) and CCR5 are involved in various inflammation and immune responses, and regulate the progression of the autoimmune diseases differently. However, the number of residues identified at the binding interface was not sufficient to clarify the differences in the CCR1- and CCR5-binding modes to MIP-1α, because the NMR measurement time for CCR1 and CCR5 samples was limited to 24 h, due to their low stability. Here we applied a recently developed NMR spectra reconstruction method, Conservation of experimental data in ANAlysis of FOuRier, to the amide-directed transferred cross-saturation experiments of chemokine receptors, CCR1 and CCR5, embedded in lipid bilayers of the reconstituted high density lipoprotein, and MIP-1α. Our experiments revealed that the residues on the N-loop and ß-sheets of MIP-1α are close to both CCR1 and CCR5, and those in the C-terminal helix region are close to CCR5. These results suggest that the genetic influence of the single nucleotide polymorphisms of MIP-1α that accompany substitution of residues in the C-terminal helix region, E57 and V63, would provide clues toward elucidating how the CCR5-MIP-1α interaction affects the progress of autoimmune diseases.

Identification of a Conformational Equilibrium That Determines the Efficacy and Functional Selectivity of the µ-Opioid Receptor.

G-protein-coupled receptor (GPCR) ligands impart differing degrees of signaling in the G-protein and arrestin pathways, in phenomena called "biased signaling". However, the mechanism underlying the biased signaling of GPCRs is still unclear, although crystal structures of GPCRs bound to the G protein or arrestin are available. In this study, we observed the NMR signals from methionine residues of the µ-opioid receptor (µOR) in the balanced- and biased-ligand-bound states. We found that the intracellular cavity of µOR exists in an equilibrium between closed and multiple open conformations with coupled conformational changes on the transmembrane helices 3, 5, 6, and 7, and that the population of each open conformation determines the G-protein- and arrestin-mediated signaling levels in each ligand-bound state. These findings provide insight into the biased signaling of GPCRs and will be helpful for development of analgesics that stimulate µOR with reduced tolerance and dependence.

Functional dynamics of deuterated ß2 -adrenergic receptor in lipid bilayers revealed by NMR spectroscopy.

G-protein-coupled receptors (GPCRs) exist in conformational equilibrium between active and inactive states, and the former population determines the efficacy of signaling. However, the conformational equilibrium of GPCRs in lipid bilayers is unknown owing to the low sensitivities of their NMR signals. To increase the signal intensities, a deuteration method was developed for GPCRs expressed in an insect cell/baculovirus expression system. The NMR sensitivities of the methionine methyl resonances from the ß2 -adrenergic receptor (ß2 AR) in lipid bilayers of reconstituted high-density lipoprotein (rHDL) increased by approximately 5-fold upon deuteration. NMR analyses revealed that the exchange rates for the conformational equilibrium of ß2 AR in rHDLs were remarkably different from those measured in detergents. The timescales of GPCR signaling, calculated from the exchange rates, are faster than those of receptor tyrosine kinases and thus enable rapid neurotransmission and sensory perception.

Design of easily swallowable xerogel pill with enough physical strength through hardening-process under heating and humidification.

The xerogel pill has been developed as a novel dosage form with dose-adjusting and swallow-assisting functions by using drop freeze-drying (DFD) technique. It was double-structured small sphere composed of an inner drug core and an outer dried-gel layer, however, had problem of insufficient physical strength. In this study, it was attempted to use dextrin (DEX), one of oligosaccharides, to strengthen the xerogel pill. DEX was co-dissolved in the dropping fluid in the DFD process and co-loaded in the conventional pill, which was mainly composed of mannitol (MNT) as a filler, to prepare the rigid body. DEX-loaded pill could be successfully prepared with high recovery (>90 %) by optimizing the ratio of DEX and MNT. Further, the representative pills with and without DEX (P-DEX and P-MNT, respectively) were hardening-processed under humidification. The physical strength of P-DEX pill was significantly increased when humidified under severe condition, resulting in enough hardness (>5N) and friability (<1.0 %). Processed P-DEX was found to have dense structure covered with a thick outer shell, which would be formed by interparticle bridge of DEX. It was also found that processed P-DEX pill suppressed initial drug dissolution significantly and exhibited sustained dissolution behavior, suggesting the potential function of bitter taste masking. Processed P-DEX pill had excellent sliding behavior with low friction forces as a result of lubricant effect of xanthan gum (XG) surrounding the pills. Furthermore, the sliding test also suggested that processed P-DEX pill had hard candy-like texture, in contrast unprocessed P-DEX pill had orally disintegrating (OD) tablet-like texture. Various xerogel pills with such different swallowing texture would have a potential to accommodate the children's preferences when taking medication.

Preparation of sustained-release tablets using a solventless-mixing tablet coating technique: Particle design of dry ammonioalkyl methacrylate copolymer latex with high coating performance using sodium lauryl sulfate.

The aim of this study was to produce sustained-release tablets by V-shaped blending of polymer and tablets without using solvents or heating, and we investigated the design of polymer particles with high coating performance by modifying the structure of the particles using sodium lauryl sulfate. Dry-latex particles of ammonioalkyl methacrylate copolymer were prepared by adding the surfactant into aqueous latex, followed by freeze drying. The resulting dry latex was mixed with tablets (1:10) using a blender and the resulting coated tablets were characterized. Tablet coating by the dry latex was promoted as the weight ratio of surfactant to polymer increased. At a surfactant ratio of 5%, deposition of the dry latex was most effective and the resulting coated tablets (annealed at 60 °C/75%RH for 6 h) exhibited sustained-release characteristics over a period of 2 h. The addition of SLS prevented coagulation of colloidal polymer in the freeze drying, resulting in a loose-structured dry latex. This latex was easily pulverized by V-shaped blending with tablets and the resulting fine particles with high adhesiveness were deposited on the tablets. However, at a surfactant ratio of 10%, the coating of dry latex decreased due to reduced adhesiveness.

[Homogeneity of Two Semisolid Formulations Using Simple In-tube Mixing Method].

To accelerate therapeutic effects, the mixtures of two or more topical pharmaceutical products having different medicinal purposes are often applied in the medical field. In this study, we aimed to develop a simple mixing method/procedure to achieve excellent homogeneity in the mixture of two topical products, a steroidal ointment and a skin moisturizer. To assess an in-tube mixing method as a simple mixing procedure, we injected both topical products into an empty resin tube, a flexible hollow tube with an open end that can be closed on one side, and a closed end on the other, removed as less air as possible inside the tube, and then thermocompressed (sealed) the open end to close it. The two topical products were then mixed uniformly by repeated finger pressure along the longitudinal axis of the tube. The homogeneity of the two topical products in the tube was evaluated by measuring the content of methyl paraoxybenzoate (MP), an additive loaded in the skin moisturizer. In addition, the mixability was qualitatively evaluated from the distribution of white petrolatum, another additive loaded in the steroid ointment, using Raman spectroscopy. As a result, the measured value of MP relative to the label claim was in the range of 100±12%, and the coefficients of variation value was also less than 12%. These results indicate that the in-tube mixing method using two topical products is approximately hologenetic preparations that do not cause therapeutic problems.

Participation of medical students in the medical team of sports events.

Including medical student volunteers in the medical team for the triathlon strengthens the medical team structure, and encourages medical students to involve in sports medicine. Family physicians who play a role in the medical team for sports events can adopt medical students as a member and can educate them.

Lipid nanoparticle-targeted mRNA formulation as a treatment for ornithine-transcarbamylase deficiency model mice.

Ornithine transcarbamylase (OTC) plays a significant role in the urea cycle, a metabolic pathway functioning in the liver to detoxify ammonia. OTC deficiency (OTCD) is the most prevalent urea cycle disorder. Here, we show that intravenously delivered human OTC (hOTC) mRNA by lipid nanoparticles (LNP) was an effective treatment for OTCD by restoring the urea cycle. We observed a homotrimer conformation of hOTC proteins produced by the mRNA-LNP in cells by cryo-electron microscopy. The immunohistochemistry revealed the mitochondria localization of produced hOTC proteins in hepatocytes in mice. In livers of mice intravenously injected with hOTC-mRNA/LNP at 1.0 mg/kg, the delivered hOTC mRNA levels steeply decreased with a half-life (t1/2) of 7.1 h, whereas the produced hOTC protein levels retained for 5 days and then declined with a t1/2 of 2.2 days. In OTCD model mice (high-protein diet-fed Otcspf-ash hemizygous males), a single dose of hOTC-mRNA/LNP at 3.0 mg/kg ameliorated hyperammonemia and weight loss with prolonged survival rate (22 days) compared with that of untreated mice (11 days). Weekly repeated doses at 0.3 and 1.0 mg/kg were well tolerated in wild-type mice and showed a dose-dependent amelioration of survival rate in OTCD mice, thus, showing the therapeutic potential of LNP-formulated hOTC mRNA for OTCD.

Evaluation of disintegration properties of orally rapidly disintegrating tablets using a novel disintegration tester.

This report describes a new disintegration tester that can determine not only the disintegration time of orally rapidly disintegrating tablets (ODT), but also the disintegration behavior and mechanism. Using the tester, the disintegration properties of the tablets prepared in a previous study were examined. The purpose of this study is to confirm the utility of the tester as an instrument for evaluating the disintegration properties of ODT and determine relations among time, behavior and mechanism of the disintegration. Results demonstrated that in vitro disintegration time in the tester is similar to that in the commercial disintegration tester for ODT and is highly correlated with oral disintegration time. Observations of disintegration process revealed that a difference in disintegration behavior between tablets compressed at 50-75 MPa and 100 MPa; the disintegration behavior of the tablets were designated immediate disintegrating type and gradual disintegrating type, respectively. The dynamic swelling profile and water absorption profile indicated that the disintegration mechanism of the tablets involved wicking action induced by swelling of the disintegrant; the disintegration time was closely related to the initial rates of swelling and water absorption. Furthermore, the mechanism of water absorption of tablets compressed at 50-75 MPa and 100 MPa shows anomalous diffusion and case-II transport, respectively. The shift in this mechanism is consistent with differences in disintegration time and behavior between the tablets. These findings suggest that information on disintegration properties obtained by our tester is useful for understanding of disintegration phenomena of ODT.

Coronary arterial wall disruption and intramural hematoma in a patient with coronary spastic angina.

Acute myocardial infarction is sometimes complicated in patients with coronary spastic angina. The mechanisms are known to be plaque rupture and thrombosis induced by spasm, and reduced coronary flow due to prolonged spasm. We describe the case of a 45-year-old woman with coronary spastic angina who had a complication of an acute myocardial infarction. A specimen obtained with thrombectomy was the disrupted coronary artery wall accompanied by massive intramural hemorrhage. The cause of the acute myocardial infarction was thought to be an embolism of the coronary arterial wall that was disrupted by spasm and intramural hemorrhage.

Solventless amorphization and pelletization using a high shear granulator. Part II; Preparation of co-amorphous mixture-layered pellets using indomethacin and arginine.

The aim of this study was to investigate the preparation of co-amorphous mixture-layered pellets using solventless pelletization and amorphization using a high shear granulator (as suggested in the first part of this study) by high shear mixing of drug crystals and a crystalline co-former with inactive spheres. Mixtures of crystalline indomethacin and arginine at various molar ratios were mixed with microcrystalline cellulose spheres at a weight ratio of 1:10 using the granulator and the resulting particles were characterized using solid-state and particle analytical techniques as well as dissolution testing and physical stability. At jacket temperatures of 20 °C or more of the granulator, co-processing of indomethacin and arginine enhanced amorphization of indomethacin and provided a co-amorphous mixture due to homogenous mixing of indomethacin and arginine amorphous phases. The co-amorphous mixture was deposited on the surface of the spheres, yielding co-amorphous mixture-layered pellets. The co-amorphous mixtures at molar ratios of indomethacin to arginine of 2:1 and 1:1, deposited on the pellets, did not recrystallize for at least 4 weeks. The pellets exhibited higher dissolution characteristics as additional hypromellose could prevent precipitation. These findings demonstrate the potential of this technique as a solventless approach to prepare co-amorphous mixture-layered pellets through a one-step process.

Solventless amorphization and pelletization using a high shear granulator. Part I; feasibility study using indomethacin.

The aim of the current study was to investigate the feasibility of solventless amorphization and pelletization using a high shear granulator, to produce amorphous drug-layered pellets by simply mixing drug crystals and inactive spheres without using solvent and heating. Indomethacin crystals were mixed with microcrystalline cellulose spheres at a weight ratio of 1:10 using the granulator and the resulting particles were then characterized using solid-state and particle analytical techniques as well as pharmaceutically relevant tests. Amorphization of indomethacin crystals progressed with increasing processing time and decreasing jacket temperature. The amorphization rate increased as the spheres became larger and full amorphization was achieved using spheres of 414 and 649 µm in diameter. Indomethacin crystals were pulverized due to mechanical activation by the spheres and the resulting amorphous microparticles were then deposited on the spheres, yielding pellets with an amorphous layer. The pellets exhibited supersaturation characteristics and the dissolution rate was faster than that of quench-cooled indomethacin powder. However, the amorphous drug deposited on the pellets exhibited a lower physical stability than quench-cooled amorphous indomethacin, but recrystallization could be inhibited by co-processing with polyvinylpyrrolidone K-25 stabilizing the amorphous form. The findings suggest the feasibility of the solventless amorphization and pelletization technique.