Allergy immunotherapy (AIT) plays a pivotal role in the treatment of type I allergic conditions such as allergic rhinitis and rhinoconjunctivitis. However, AIT faces persistent issues, notably the risk of anaphylaxis and the need for long-term treatment. To address these issues, various strategies have been explored, including the use of adjuvants, allergen delivery systems, and allergen modifications. This study used a prophylactic mouse model of allergic sensitization to explore the potential for improving the efficacy and safety of Japanese cedar pollen (JCP) subcutaneous immunotherapy (SCIT). In this model, JCP extract was combined with an adjuvant (K3 CpG oligodeoxynucleotide [CpG-ODN]) and/or a delivery system (dilauroyl phosphatidylcholine/deoxycholic acid [DLPC/DA] micelles) for subcutaneous immunization of naïve mice. Compared to immunization with JCP alone, the combination of JCP with K3 CpG-ODN and DLPC/DA micelles resulted in a general reduction of the JCP-induced T-helper 2 (Th2) immune response, including reduced airway inflammation and allergen-specific plasma immunoglobulin E. In addition, Th1 markers were either largely unaffected (interferon-γ) or markedly increased (allergen-specific plasma IgG2a). These immunological changes coincided with reduced sneezing frequency in response to allergen exposure. For most parameters, a synergistic effect was observed when both K3 CpG-ODN and DLPC/DA micelles were combined with JCP at the time of immunization. In conclusion, the data presented here indicate that the combination of JCP, K3 CpG-ODN, and DLPC/DA micelles is a promising candidate for the development of a more effective SCIT treatment for Japanese cedar pollinosis, which may include a shorter treatment regimen and reduced risk of anaphylactic reactions.

Caco-2 cells, derived from colorectal cancer cells, are generally used to evaluate drug absorption in the gastrointestinal tract. However, differences between Caco-2 and normal intestinal cells have been observed. Cells cultured directly from crypts are maintained in their biological state. Therefore, we developed a rapid and easy method of monolayer culture of epithelial cells isolated from the jejunum of mice. We analyzed the usefulness of the jejunal epithelial cell monolayer culture system as a research tool and evaluated changes in the transport activity and mRNA expression of transporters. We focused on P-glycoprotein (P-gp) and peptide transporter 1 (Pept1) as representative transporters expressed in the small intestine. A P-gp inhibitor significantly enhanced the accumulation of Rhodamine 123 (Rho123), a substrate of P-gp, indicating that the transport activity of P-gp could be evaluated. Uptake of glycylsarcosine, a Pept1 substrate, significantly decreased in the presence of the Pept1 inhibitor, indicating that the transport activity of Pept1 could be evaluated. Rho123 accumulation significantly decreased in the group treated with calcitriol, an inducer of P-gp and Cyp3a11, suggesting that changes in P-gp expression could be evaluated. Furthermore, we examined whether mRNA expression levels of transporters and drug-metabolizing enzyme were altered. In the calcitriol-supplemented group, P-gp and Cyp3a11 mRNA levels significantly increased. However, no significant differences were observed in Pept1 mRNA levels. Overall, the jejunal epithelial cell monolayer culture system developed from intestinal tissues is a useful research tool for assessing the transport activities and expression variabilities of transporters.

Vascular endothelial cells (VECs) and lymphatic endothelial cells (LECs) regulate the homeostasis of fluids, nutrients, and immune cells in the blood and lymphatic systems, respectively. These specialized functions depend on distinct cell-surface proteins and tightly regulated endocytic pathways, but the molecular determinants underlying the cell-type-specific endocytic profiles of these cells remain unclear. We sought to quantitatively characterize and compare the endocytic cell-surface proteomes of human umbilical vein endothelial cells (HUVECs) and human dermal LECs (HDLECs) using cell-surface biotinylation and internalization assays combined with sequential window acquisition of all theoretical fragment ion spectra-MS–based quantitative proteomics. HUVECs and HDLECs had a similar number of cell-surface and internalized proteins, with substantial overlap, but also included sets unique to each cell type. We identified 32 HUVEC- and HDLEC-enriched endocytic cell-surface proteins, respectively; these proteins were present in both enriched cell-surface and internalized fractions, representing cell-type-selective endocytic proteins. Functional enrichment analysis showed that HUVEC-enriched proteins were associated with angiogenesis, nutrient uptake, and metabolism, whereas HDLEC-enriched proteins were linked to immune regulation, extracellular matrix organization, and lymphangiogenesis. In conclusion, our present study demonstrates that VECs and LECs possess distinct endocytic cell-surface protein profiles that define their specialized functions and represent promising targets for endothelial-selective drug delivery and imaging.

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are clinically used to control hyperglycemia and body weight in patients with type 2 diabetes mellitus and obesity. Despite their efficacy, GLP-1 RAs frequently induce nausea and vomiting as adverse effects, which are prominent factors for non-adherence to GLP-1 RAs. Therefore, new prophylaxes and treatments for GLP-1 RA-induced nausea are urgently needed. Here, we explored the U. S. Food and Drug Administration (FDA) Adverse Event Reporting System database to determine the effective drug combinations mitigating GLP-1 RA-induced nausea and vomiting in real-world settings. We further investigated the effects of the identified drugs on GLP-1 RA-induced pica behavior, a behavioral index of nausea in mice. Analysis of the FDA Adverse Event Reporting System revealed that therapeutics, including gabapentin and acetaminophen, significantly lowered the occurrence of nausea-related events in GLP-1 RA-treated patients. In mice, we confirmed that exenatide, a GLP-1 RA, significantly increased the pica behavior in a dose-dependent manner, without affecting the food intake. Finally, we found that co-treatment with gabapentin significantly decreased the pica behavior induced by exenatide. These results demonstrate the therapeutic efficacy of gabapentin against nausea and vomiting in patients administered GLP-1 RAs.

In this study, we investigated guanidinylated chitosan (GCS), a chemically modified derivative of unmodified low-molecular-weight chitosan (CS), as a multifunctional excipient to enhance the solubility and absorption of poorly water-soluble drugs. Flurbiprofen (FP) was selected as a model drug to compare the performance of kneaded dispersions GCS-based (FP-GCS) and CS-based (FP-CS). Both GCS and CS increased the solubility of FP in a concentration-dependent manner, with no significant differences between them. However, dissolution testing showed that FP-GCS kneaded dispersion significantly enhanced the dissolution rate of FP alone in water and simulated gastric fluid (pH 1.2), but not under simulated intestinal conditions (pH 6.8). In vivo pharmacokinetic studies in rats demonstrated that FP-GCS kneaded dispersion achieved the highest plasma concentration of FP, suggesting enhanced gastrointestinal permeability. Moreover, FP-GCS kneaded dispersion markedly reduced gastric ulceration in a rat ulcer model. These results indicate that GCS is an effective oral drug delivery excipient capable of improving both the bioavailability and gastrointestinal safety of FP.