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PurposeWhile animal and in vitro data demonstrate vasodilatory effects of egg white-derived peptides, human studies are lacking. We investigated for the first time the effects of an egg ovalbumin-derived protein hydrolysate on blood pressure (BP) and cardiovascular risk.MethodsA double-blind, placebo-controlled randomized crossover trial was implemented in 75 adults aged 50–70 years with systolic BP (130–≤ 150 mmHg). Participants were randomized to an egg ovalbumin-derived protein hydrolysate (3 g/day) or placebo (3 g/day). Participants completed two 6-week periods separated by a 3-week washout.ResultsData from 65 participants with a mean systolic BP (135.1 ± 11 mmHg) were included. Mean office and central BP and arterial stiffness (assessed by carotid-femoral pulse wave velocity (cfPWV) or pulse wave analysis (PWA)) did not change over time and no significant differences were observed between the egg protein hydrolysate and placebo groups (P > 0.05). Similarly, no significant effects of this egg ovalbumin-derived protein hydrolysate on blood lipid and glucose concentrations (P > 0.05) were observed.ConclusionThis is the first dietary intervention to investigate the effects of egg ovalbumin-derived protein hydrolysates on cardiovascular risk in humans. Despite promising findings from animal and in vitro studies, this RCT does not support the hypothesis that consumption of an egg ovalbumin-derived protein hydrolysate for 6 weeks in adults with a high-normal BP results in a reduction in BP or the modification of cardiovascular risk.

Anaphylactic shock (AS) is the most severe form of acute systemic hypersensitivity reaction. Although epinephrine can restore patients’ hemodynamics, it might also be harmful, supporting the need for adjuvant treatment. We therefore investigated whether NButGT, enhancing O-GlcNAcylation and showing beneficial effects in acute heart failure might improve AS therapy. Ovalbumin-sensitized rats were randomly allocated to six groups: control (CON), shock (AS), shock treated with NButGT alone before (AS+pre-Nbut) or after (AS+post-Nbut) AS onset, shock treated with epinephrine alone (AS+EPI) and shock group treated with combination of epinephrine and NButGT (AS+EPI+preNBut). Induction of shock was performed with an intravenous (IV) ovalbumin. Cardiac protein and cycling enzymes O-GlcNAcylation levels, mean arterial pressure (MAP), heart rate, cardiac output (CO), left ventricle shortening fraction (LVSF), mitochondrial respiration, and lactatemia were evaluated using Western blotting experiments, invasive arterial monitoring, echocardiography, mitochondrial oximetry and arterial blood samples. AS decreased MAP (−77%, p < 0.001), CO (−90%, p < 0.001) and LVSF (−30%, p < 0.05). Epinephrine improved these parameters and, in particular, rats did not die in 15 min. But, cardiac mitochondrial respiration remained impaired (complexes I + II −29%, p < 0.05 and II −40%, p < 0.001) with hyperlactatemia. NButGT pretreatment (AS+pre-Nbut) efficiently increased cardiac O-GlcNAcylation level as compared to the AS+post-Nbut group. Compared to epinephrine alone, the adjunction of NButGT significantly improved CO, LVSF and mitochondrial respiration. MAP was not significantly increased but lactatemia decreased more markedly. Pretreatment with NButGT increases O-GlcNAcylation of cardiac proteins and has an additive effect on epinephrine, improving cardiac output and mitochondrial respiration and decreasing blood lactate levels. This new therapy might be useful when the risk of AS cannot be avoided.

The challenges associated with wound healing are multifaceted, encompassing factors such as susceptibility to infection, inadequate blood supply to injured tissues, and the retention of foreign bodies. Development of a wound repair product that can effectively overcome the aforementioned issues at a relatively low cost would better meet the needs of patients. Consequently, this research aimed to develop a low-cost hydrogel with a simple preparation process to accelerate wound healing and reduce the risk of infection. Given their abundance and low cost, ovalbumin (OVA), dendrobium polysaccharide (DOPs), and erythromycin (EM) were selected as the primary components for constructing the composite hydrogel. In vitro experiments revealed that a solution containing 0.4 g/mL OVA, 50 mg/mL DOPs, and 100 µg/mL EM could effectively form a composite hydrogel when incubated in a warm bath at 53°C for 40 min. The resulting OVA/EM/DOPs hydrogel demonstrated exceptional properties, including strong adhesion, regenerative capacity, water retention, hydrophilicity, non-hemolytic behavior, and antimicrobial activity. Cellular assays further confirmed that the OVA/EM/DOPs hydrogel exhibited low cytotoxicity, excellent biocompatibility, and the ability to enhance scratch closure in L929 cells. In vivo wound healing experiments demonstrated that the composite hydrogel significantly accelerated wound repair by upregulating the expression of CD31 and VEGF while reducing levels of IL-10 and TNF-α. Both in vitro and in vivo findings consistently supported the hydrogel’s efficacy in promoting wound healing and mitigating inflammation, highlighting its considerable potential for clinical wound management. The research not only offers a promising, low-cost option for wound repair but also broadens the potential applications of DOPs. Furthermore, the successful design of this composite hydrogel provides a novel framework for developing other simple and economical hydrogel-based materials, paving the way for innovative approaches in wound care and beyond.

Dendritic cell (DC)-derived exosomes (Dexo) contain the machinery necessary to activate potent antigen-specific immune responses. As promising cell-free immunogens, Dexo have been tested in previous clinical trials for cancer vaccine immunotherapy, yet resulted in limited therapeutic benefit. Here, we explore a novel Dexo vaccine formulation composed of Dexo purified from DCs loaded with antigens and matured with either the TLR-3 ligand poly(I:C), the TLR-4 ligand LPS or the TLR-9 ligand CpG-B. When poly(I:C) was used to produce exosomes together with ovalbumin (OVA), the resulting Dexo vaccine strongly stimulated OVA-specific CD8 + and CD4 + T cells to proliferate and acquire effector functions. When a B16F10 melanoma cell lysate was used to load DCs with tumor antigens during exosome production together with poly(I:C), we obtained a Dexo vaccine capable of inducing robust activation of melanoma-specific CD8 + T cells and the recruitment of cytotoxic CD8 + T cells, NK and NK-T cells to the tumor site, resulting in significantly reduced tumor growth and enhanced survival as compared to a Dexo vaccine formulation similar to the one previously tested on human patients. Our results indicate that poly(I:C) is a particularly favorable TLR agonist for DC maturation during antigen loading and exosome production for cancer immunotherapy.

Polymeric nanoparticles (NPs) have demonstrated their potential to induce antigen (Ag)-specific immunological tolerance in multiple immune models and are at various stages of commercial development. Association of Ag with NPs is typically achieved through surface coupling or encapsulation methods. However, these methods have limitations that include high polydispersity, uncontrollable Ag loading and release, and possible immunogenicity. Here, using antigenic peptides conjugated to poly(lactide-co-glycolide), we developed Ag-polymer conjugate NPs (acNPs) with modular loading of single or multiple Ags, negligible burst release, and minimally exposed surface Ag. Tolerogenic responses of acNPs were studied in vitro to decouple the role of NP size, concentration, and Ag loading on regulatory T cell (Treg) induction. CD4+CD25+Foxp3+ Treg induction was dependent on NP size, but CD25 expression of CD4+ T cells was not. NP concentration and Ag loading could be modulated to achieve maximal levels of Treg induction. In relapsing-remitting experimental autoimmune encephalomyelitis (R-EAE), a murine model of multiple sclerosis, acNPs were effective in inhibiting disease induced by a single peptide or multiple peptides. The acNPs provide a simple, modular, and well-defined platform, and the NP physicochemical properties offer potential to design and answer complex mechanistic questions surrounding NP-induced tolerance. [Display omitted] Pearson et al. have developed Ag-polymer conjugate PLG (acNP) nanoparticles that display modular Ag loading, negligible burst release, and minimally exposed surface Ag that are effective at treating EAE induced by a single peptide or multiple peptides. This approach has the potential to simultaneously deliver and induce tolerance to multiple disease-relevant antigens.

Targeted approaches to treat autoimmune diseases would improve upon current therapies that broadly suppress the immune system and lead to detrimental side effects. Antigen-specific tolerance was induced using poly(lactide-co-glycolide) nanoparticles conjugated with disease-relevant antigen to treat a model of multiple sclerosis. Increasing the nanoparticle dose and amount of conjugated antigen both resulted in more durable immune tolerance. To identify active tolerance mechanisms, we investigated downstream cellular and molecular events following nanoparticle internalization by antigen-presenting cells. The initial cell response to nanoparticles indicated suppression of inflammatory signaling pathways. Direct and functional measurement of surface MHC-restricted antigen showed positive correlation with both increasing particle dose from 1 to 100 μg/mL and increasing peptide conjugation by 2-fold. Co-stimulatory analysis of cells expressing MHC-restricted antigen revealed most significant decreases in positive co-stimulatory molecules (CD86, CD80, and CD40) following high doses of nanoparticles with higher peptide conjugation, whereas expression of a negative co-stimulatory molecule (PD-L1) remained high. T cells isolated from mice immunized against myelin proteolipid protein (PLP139–151) were co-cultured with antigen-presenting cells administered PLP139–151-conjugated nanoparticles, which resulted in reduced T cell proliferation, increased T cell apoptosis, and a stronger anti-inflammatory response. These findings indicate several potential mechanisms used by peptide-conjugated nanoparticles to induce antigen-specific tolerance. Peptide-conjugated nanoparticles induce antigen-specific tolerance in models of autoimmunity. Kuo et al. investigated cellular and molecular mechanisms of antigen-presenting cells following nanoparticle internalization. Increasing peptide conjugation and delivering higher nanoparticle doses both contributed to enhanced antigen presentation, as well as reductions in co-stimulatory expression and effector T cell responses.

Interleukin 33 (IL-33) represents a potential link between the airway epithelium and induction of Th2-type inflammatory responses associated with the development of asthma. This study investigated the potential of IL-33 to exacerbate antigen driven asthma responses. An ovalbumin (OVA) asthma model was used in which sensitized C57BL/6 mice were exposed to IL-33 before each OVA challenge. IL-33 given to sensitized mice acted synergistically with antigen and aggravated airway inflammation, hyperresponsiveness and remodeling compared with mice that were only OVA sensitized and challenged and mice that were only exposed to IL-33. Elevated levels of local and systemic mast cell protease mMCP-1, as well as antigen-specific IgE production, were observed following IL-33 administration to sensitized mice. Similarly, exposing OVA-sensitized mice to IL-33 increased the Th2 cytokine levels, including IL-4, IL-5 and IL-13. Furthermore, IL-33 and OVA administration to OVA-sensitized mice increased ILC2s in the lung, suggesting a role for ILC2s in IL-33-mediated exacerbation of OVA-induced airway responses. Collectively, these findings show that IL-33 aggravates important features of antigen-driven asthma, which may have implications for asthma exacerbations.

The increasing prevalence of food sensitivities has been attributed to changes in gut microenvironment; however, ubiquitous environmental triggers such as inorganic nanoparticles (NPs) used as food additives have not been thoroughly investigated. We explored the impact of the NP-structured food-grade silicon dioxide ( ) on intestinal immune response involved in oral tolerance (OT) induction and evaluated the consequences of oral chronic exposure to this food-additive using a mouse model of OT to ovalbumin (OVA) and on gluten immunopathology in mice expressing the celiac disease risk gene, HLA-DQ8. Viability, proliferation, and cytokine production of mesenteric lymph node (MLN) cells were evaluated after exposure to . C57BL/6J mice and a mouse model of OT to OVA were orally exposed to or vehicle for 60 d. Fecal lipocalin-2 (Lcn-2), anti-OVA IgG, cytokine production, and immune cell populations were analyzed. Nonobese diabetic (NOD) mice expressing HLA-DQ8 (NOD/DQ8), exposed to or vehicle, were immunized with gluten and immunopathology was investigated. MLN cells exposed to presented less proliferative T cells and lower secretion of interleukin 10 (IL-10) and transforming growth factor beta ( ) by T regulatory and cells compared to control, two factors mediating OT. Mice given exhibited intestinal Lcn-2 level and interferon gamma ( ) secretion, showing inflammation and less production of IL-10 and . These effects were also observed in OVA-tolerized mice exposed to , in addition to a breakdown of OT and a lower intestinal frequency of T cells. In NOD/DQ8 mice immunized with gluten, the villus-to-crypt ratio was decreased while the intraepithelial lymphocyte counts and the Th1 inflammatory response were aggravated after treatment. Our results suggest that chronic oral exposure to blocked oral tolerance induction to OVA, and worsened gluten-induced immunopathology in NOD/DQ8 mice. The results should prompt investigation on the link between exposure and food sensitivities in humans. https://doi.org/10.1289/EHP12758.

A positive relationship between obesity and asthma has been well documented. The AMP-activated protein kinase (AMPK) activator metformin reverses obesity-associated insulin resistance (IR) and inhibits different types of inflammatory responses. This study aimed to evaluate the effects of metformin on the exacerbation of allergic eosinophilic inflammation in obese mice. Male C57BL6/J mice were fed for 10 weeks with high-fat diet (HFD) to induce obesity. The cell infiltration and inflammatory markers in bronchoalveolar lavage (BAL) fluid and lung tissue were evaluated at 48 h after ovalbumin (OVA) challenge. HFD obese mice displayed peripheral IR that was fully reversed by metformin (300 mg/kg/day, two weeks). OVA-challenge resulted in higher influx of total cell and eosinophils in lung tissue of obese mice compared with lean group. As opposed, the cell number in BAL fluid of obese mice was reduced compared with lean group. Metformin significantly reduced the tissue eosinophil infiltration and prevented the reduction of cell counts in BAL fluid. In obese mice, greater levels of eotaxin, TNF-α and NOx, together with increased iNOS protein expression were observed, all of which were normalized by metformin. In addition, metformin nearly abrogated the binding of NF-κB subunit p65 to the iNOS promoter gene in lung tissue of obese mice. Lower levels of phosphorylated AMPK and its downstream target acetyl CoA carboxylase (ACC) were found in lung tissue of obese mice, which were restored by metformin. In separate experiments, the selective iNOS inhibitor aminoguanidine (20 mg/kg, 3 weeks) and the anti-TNF-α mAb (2 mg/kg) significantly attenuated the aggravation of eosinophilic inflammation in obese mice. In conclusion, metformin inhibits the TNF-α-induced inflammatory signaling and NF-κB-mediated iNOS expression in lung tissue of obese mice. Metformin may be a good pharmacological strategy to control the asthma exacerbation in obese individuals.

Inhaled corticosteroids, including budesonide (BUD), are widely employed for the treatment of asthma. However, the frequent use of corticosteroids is associated with numerous adverse effects and poses challenges to ongoing drug therapy and patient adherence. Budesonide liposomal nanoparticles (BUD-LNPs) were developed to improve the bioavailability of the drug and thereby improve the effectiveness of asthma treatment. BUD-LNPs were prepared via thin-film hydration, and the characterizations, stability, and in vitro release of BUD-LNPs were studied. In vitro cellular uptake was observed by laser-scanning confocal microscope (LSCM) and flow cytometry. And the in vitro anti-inflammatory activity of BUD-LNPs was evaluated by measuring the expression of pro-inflammatory cytokines in activated macrophages. Besides, the accumulation time in the lung of drugs delivered via liposomal carriers and free drugs was compared in vivo. And the in vivo therapeutic efficacy of BUD-LNPs was assessed in OVA-induced asthmatic mice. Finally, in vivo biosafety assessment was performed. The particle size, PDI, and zeta potential of BUD-LNPs were 127.63±1.33 nm, 0.27±0.02, and 3.33±0.13 mV, respectively. BUD-LNPs exhibited excellent biosafety and anti-inflammatory activity in vitro. Furthermore, compared with the free drugs, the utilization of liposomal nano-vehicles for drugs delivery could effectively extend the duration of drugs accumulation in the pulmonary system. Additionally, treatment with BUD-LNPs alleviated airway hyperresponsiveness, reduced airway mucus secretion, and mitigated pulmonary inflammation in OVA-induced asthmatic mice. And the BUD-LNPs demonstrated superior therapeutic efficacy compared to free BUD. BUD-LNPs was successfully prepared with excellent stability and sustained release for 24 h in vitro. The data of anti-inflammatory activity, asthma therapeutic effects and safety studies indicated that drug delivery mediated by liposomal nano-vehicles was a feasible and desirable strategy for medical strategy and showed great promise in the clinical therapy of asthma.