Head-to-head comparison of influenza vaccines in children: a systematic review and meta-analysis.

Although vaccination is considered the most effective weapon against influenza, coverage rates, national vaccination policies, and funding vary largely around the globe. Despite their huge potential for achieving herd immunity, child-focused national vaccination strategies that favor pain-free nasal vaccines are uncommon. CENTRAL, Embase, and MEDLINE were last searched on November 13, 2023. Active-controlled randomized controlled trials comparing the live-attenuated intranasal vaccine with the inactivated intramuscular influenza vaccine in children were included. Event rates of laboratory-confirmed influenza virus infection, all-cause mortality, hospitalization, serious adverse events, adverse events, and financial outcomes were extracted based on the PRISMA 2020 Guideline. PROSPERO: CRD42021285412. Pooled odds ratios (ORs) with 95% confidence intervals (CI) were calculated using the random-effects model when at least three comparable outcomes were available. We found no significant difference between quadrivalent live-attenuated intranasal and trivalent inactivated intramuscular (OR = 1.48; 95% CI 0.49-4.45) or between trivalent live-attenuated intranasal and inactivated intramuscular vaccines (OR = 0.77, CI = 0.44-1.34) regarding their efficacy. However, the subgroup analysis of large, multi-center trials indicated that the trivalent live attenuated intranasal influenza vaccine was superior to the trivalent inactivated intramuscular influenza vaccine (12,154 people, OR = 0.50, CI = 0.28-0.88). Only 23 "vaccine-related serious adverse events" were recorded among 17 833 individuals, with no significant difference between methods. The widespread initiation of pediatric national flu vaccination programs prioritizing the live-attenuated intranasal influenza vaccine would be beneficial. Multi-continent, high-quality studies that include children younger than two years old and those living in subtropical and tropical regions are needed to further enhance our understanding.

A Prime-Boost Vaccination Approach Induces Lung Resident Memory CD8+ T Cells Derived from Central Memory T Cells That Prevent Tumor Lung Metastasis.

Memory T cells play a key role in immune protection against cancer. Vaccine-induced tissue-resident memory T (TRM) cells in the lung have been shown to protect against lung metastasis. Identifying the source of lung TRM cells can help to improve strategies, preventing tumor metastasis. Here, we found that a prime-boost vaccination approach using intramuscular DNA vaccine priming, followed by intranasal live-attenuated influenza-vectored vaccine (LAIV) boosting induced higher frequencies of lung CD8+ TRM cells compared with other vaccination regimens. Vaccine-induced lung CD8+ TRM cells, but not circulating memory T cells, conferred significant protection against metastatic melanoma and mesothelioma. Central memory T (TCM) cells induced by the DNA vaccination were major precursors of lung TRM cells established after the intranasal LAIV boost. Single-cell RNA sequencing analysis indicated that transcriptional reprogramming of TCM cells for differentiation into TRM cells in the lungs started as early as day 2 post the LAIV boost. Intranasal LAIV altered the mucosal microenvironment to recruit TCM cells via CXCR3-dependent chemotaxis and induced CD8+ TRM-associated transcriptional programs. These results identified TCM cells as the source of vaccine-induced CD8+ TRM cells that protect against lung metastasis. Significance: Prime-boost vaccination shapes the mucosal microenvironment and reprograms central memory T cells to generate lung resident memory T cells that protect against lung metastasis, providing insights for the optimization of vaccine strategies.

Efficacy and Safety of Ketamine/Esketamine in Bipolar Depression in a Clinical Setting.

Background: Bipolar disorder represents a significant source of morbidity and elevated mortality risk. Ketamine has emerged as a powerful antidepressant; however, there have been few trials of ketamine in bipolar depression and no trials with esketamine in bipolar depression, and few data exist from real-world settings. Here, we report outcomes from a cohort of patients with bipolar depression treated with ketamine/ esketamine in a real-world setting.Methods: Patients with treatment refractory bipolar depression were referred to Yale Psychiatric Hospital Interventional Services for treatment from October 2014 to November 2023. Appropriate patients were treated with intravenous (IV) ketamine (0.5 mg/kg over 40 minutes) or intranasal esketamine (56 or 84 mg). Diagnosis of bipolar depression was done by clinical evaluation by an attending psychiatrist, based on DSM criteria. Clinical outcomes were tabulated from medical records.Results: Overall, 45 patients with bipolar depression were treated with IV ketamine or intranasal (IN) esketamine during the time period specified. Depression severity outcomes were available for 38 patients that completed an acute series, defined as treatment twice weekly for up to 4 weeks. Overall, 15/38 (39%) achieved clinical response (≥50% improvement on the Montgomery-Asberg Depression Rating Scale [MADRS]) and 5/38 (13.2%) achieved remission (≤10 on MADRS) following the acute series. Mean MADRS scores decreased from 31.1 to 19.2 (38.3% mean improvement). Safety data (hypomania/manic symptoms) were available for all 45 patients (518 patient-months of follow-up). No patients experienced any mania/hypomania during the acute series phase (when treatments are given twice weekly). However, 13/45 (28.9%) patients experienced symptoms consistent with a hypomanic or manic episode at some point following the acute phase while continuing to receive ketamine or esketamine during a maintenance phase. There were 16 manic/hypomanic events, indicating 1 event for every 2.7 patient-years. Only 1 event was severe and resulted in hospitalization.Conclusion: In a small sample of patients with bipolar depression treated with ketamine/esketamine, no evidence of mania/hypomania was seen during the acute phase of treatment. Further research is needed to evaluate whether ketamine or esketamine confers heightened risk of affective switch during maintenance treatment.

Comparative pathogenicity of influenza virus-induced pneumonia mouse model following intranasal and aerosolized intratracheal inoculation.

BACKGROUND: Infection of mice with mouse-adapted strains of influenza virus has been widely used to establish mouse pneumonia models. Intranasal inoculation is the traditional route for constructing an influenza virus-induced pneumonia mouse model, while intratracheal inoculation has been gradually applied in recent years. In this article, the pathogenicity of influenza virus-induced pneumonia mouse models following intranasal and aerosolized intratracheal inoculation were compared. METHODS: By comparing the two ways of influenza inoculation, intranasal and intratracheal, a variety of indices such as survival rate, body weight change, viral titer and load, pathological change, lung wet/dry ratio, and inflammatory factors were investigated. Meanwhile, the transcriptome was applied for the initial exploration of the mechanism underlying the variations in the results between the two inoculation methods. RESULTS: The findings suggest that aerosolized intratracheal infection leads to more severe lung injury and higher viral loads in the lungs compared to intranasal infection, which may be influenced by the initial site of infection, sialic acid receptor distribution, and host innate immunity. CONCLUSION: Intratracheal inoculation is a better method for modelling severe pneumonia in mice than intranasal infection.

Intranasal human-recombinant nerve growth factor administration improves cognitive functions in a child with severe traumatic brain injury.

BACKGROUND: Behavioral and neuropsychological functions are frequent long-term sequelae of severe traumatic brain injury (TBI). Neuropeptides, such as nerve growth factor (NGF), can enhance neurogenesis and improve cognitive functions after TBI, playing a pivotal role in neuroplasticity. A limited number of studies documented the safety and efficacy of intranasal NGF administration in children with severe TBI. CASE REPORT: A fourteen-year-old boy with a diffuse axonal injury secondary to severe TBI was treated with human-recombinant NGF administration. This patient underwent treatment with intranasal hr-NGF administration at a total dose of 50 gamma/kg, three times a day for seven consecutive days. The treatment schedule was performed for 4 cycles, at one month distance each. NGF administration improved radiologic functional assessment evaluated with positron emission tomography scan (PET) and single photon emission computed tomography (SPECT), with an important improvement in clinical conditions. Significant improvements were also observed, mainly in cognitive processes, memory, the planning of a communication strategy, execution skills, attention, and verbal expression. No side effects were reported. CONCLUSIONS: Additional studies are required to gain a deeper insight into this neurotrophin's neuroprotective function, but our findings reveal a potential efficacy of intranasal hr-NGF administration in enhancing cognitive and clinical outcomes among children with diffuse axonal injury after severe TBI.

Therapeutic efficacy of JEW-M449, an anti-TCTP monoclonal antibody, administered via the nasal route in a BALB/c mouse model of ovalbumin-induced acute asthma.

Numerous studies have highlighted the role of translationally controlled tumor protein (TCTP) as a key inflammatory mediator of asthma and allergies. Our previous study revealed that blocking the cytokine-like activity of TCTP using JEW-M449, an anti-TCTP monoclonal antibody (mAb), alleviated allergic inflammation in asthmatic mice. This study aimed to determine whether directly delivering JEW-M449 into the respiratory tract is a more effective way of mitigating airway inflammation in a mouse model of ovalbumin (OVA)-induced allergic airway inflammation than delivering this antibody via the intraperitoneal (IP) route. OVA-sensitized mice were intranasally administered JEW-M449 to enable its direct delivery to the respiratory tract before OVA challenge. We evaluated the changes in the levels of bronchoalveolar lavage fluid (BALF) cells, T helper type 2 (Th2) cytokines, OVA-specific immunoglobulin E (IgE), and histopathological alterations in the lung tissues. Intranasal (IN) administration of JEW-M449 significantly ameliorated the pathological changes associated with OVA-induced lung injury, including reduced inflammatory cell infiltration and mucus hypersecretion. Mice IN administered JEW-M449 also showed decreased OVA-mediated induction of Th2 cytokines in BALF and lung homogenates. Importantly, JEW-M449 delivered via the IN route reached the lung tissue more effectively and exerted superior anti-inflammatory effects in OVA-challenged mice than the IP-delivered JEW-M449. This study is the first to demonstrate the efficacy of directly delivering JEW-M449 anti-TCTP mAb into the respiratory tract to alleviate the asthma phenotype in a mouse model, thereby highlighting a potential delivery strategy for novel inhaled mAb therapeutics for human asthma.

Efficacy and safety of various corticosteroids in the treatment of children with allergic rhinitis: A systematic review and network meta-analysis.

BACKGROUND: Intranasal corticosteroids were recommended as first-line drugs for the treatment of allergic rhinitis (AR) children. A variety of corticosteroids were available for clinical choice; however, which could relieve the clinical symptoms of patients to the greatest extent was currently unknown. Thus, we performed a network meta-analysis (NMA) to systematically evaluate the effectiveness and safety of different corticosteroids in treating children with AR, which might provide a basis for more rational clinical treatment decisions. METHODS: Seven electronic databases were searched, and the retrieval time range was the time from their inception to November 2023. The literature screening, data extraction, and assessment of the risk of bias of included studies were completed independently by two reviewers. A frequentist NMA was performed with Stata17.0 software. RESULTS: A total of 43 RCTs covering 10,897 participants were included. In the improvement of reflective total nasal symptom score (rTNSS) and instantaneous total nasal symptom score (iTNSS), fluticasone furoate nasal spray (FFNS) and beclomethasone dipropionate (BDP) nasal aerosol presented the best efficacy. Regarding the incidence of adverse reactions, mometasone furoate aqueous nasal spray (MFANS) and BDP showed a good safety profile. In terms of the influence of cortisol (urinary free cortisol, plasma cortisol) and growth, no significant difference was observed between the different groups. CONCLUSION: The results showed that BDP nasal aerosol and FFNS had best efficacy; MFANS and BDP had the best safety profile. However, this conclusion was less convincing because of the limited numbers of patients/controls and study quality.

Pharmacological Activation and Transgenic Overexpression of SIRT1 Attenuate Traumatic Optic Neuropathy Induced by Blunt Head Impact.

Purpose: Resveratrol (RSV) is a nutraceutical compound known for its therapeutic potential in neurodegenerative and metabolic diseases. RSV promotes survival signals in retinal ganglion cells (RGCs) through activation of SIRT1, an NAD+-dependent deacetylase. RSV and SIRT1 reduce RGC loss induced by direct optic nerve injury, but effects in indirect models of traumatic optic neuropathy remain unknown and are examined in this study. Methods: An electromagnetic stereotaxic impactor device was used to impart five traumatic skull impacts with an inter-concussion interval of 48 hours to wild type (WT) and SIRT1 knock in (KI) C57BL/6J mice overexpressing the SIRT1 gene. A cohort of WT mice also received intranasal administration of RSV (16 mg/kg) throughout the experimental period. Loss of righting reflex (RR), optokinetic response (OKR) scores, and immunolabeled RGC count are determined to assess optic neuropathy in this model of traumatic brain injury (TBI). Results: TBI significantly decreases RGC survival and decreases OKR scores compared with control uninjured mice. Either RSV administration in WT mice, or SIRT1 overexpression in SIRT1 KI mice, significantly increases RGC survival and improves OKR scores. RR time increases after the first few impacts in all groups of mice subjected to TBI, demonstrating that RSV and SIRT1 overexpression are able to attenuate optic neuropathy following similar degrees of TBI. Conclusions: Intranasal RSV is effective in preserving visual function in WT mice following TBI. Constitutive overexpression of SIRT1 recapitulates the neuroprotective effect of RSV. Translational Relevance: Results support future exploration of RSV as a potential therapy for indirect traumatic optic neuropathy.

Formulation and development of frovatriptan succinate in situ gel for nasal drug delivery: In vitro and ex vivo evaluation.

Magrain is a depleting disease that sometimes requires extensive treatment, ideally with medication that targets the brain, with minimized systemic adverse effects, preferably with a single daily medication; these properties are offered partially by the current dosage form of Frovatriptan. formulation of Frovatriptan binary ethosome into mucoadhesive nasal in situ gel to extend the drug's residence time. The particle size was 154.1±4.38 nm of the Frovatriptan binary ethosome. In situ, gel formulas were prepared to utilize the cold technique, using 18%w/v poloxamer 407 with different concentrations of Carbopol 934 and the clarity, pH, Frovatriptan content spreadability, mucoadhesive force, in vitro diffusion via nasal mucosa and the optimal formula underwent further investigations. In-situ gel F2 (0.2% Carbopol) demonstrated the best spreadability of 12.88±0.186 cm2/min, 99% drug content mucoadhesive strength of 645.32±0.054 dynes/cm2, percent release of 98.56±0.041 after 24 hours and permeability increased by around 3.68-fold compared to the pure drug and histopathologically showed favorable outcomes. Mucoadhesive Frovatriptan-binary ethosome-loaded nasal in situ gel is an effective method of treating migraines.

Antibodies to Glutamate Reduce the IL-6 Content in Cerebral Structures in Mice with Age-Related Memory Impairment.

Intranasal administration of antibodies to glutamate for 14 days improved passive avoidance conditioning and reduces the content of IL-6 within 7 days after their withdrawal in the prefrontal cortex and hippocampus of aging C57BL/6 mice.

Testosterone rapidly increases men's emotion-based dehumanization of a conservatively dressed woman.

Past research has found that sexualized women are often dehumanized (i.e., attributed reduced human qualities). However, the mechanisms contributing to such dehumanization remain poorly understood. In this pre-registered experiment involving a within-subject, placebo-controlled, cross-over design, we tested whether testosterone contributes to men's (N = 120, age range: 18-38 years) dehumanization of women. After administration of intranasal testosterone or placebo gel, men watched a video of a woman wearing either modest (i.e., conservative) or revealing (i.e., sexualized) clothing (between-subjects factor) and then completed three subtle dehumanization tasks, measuring emotion-based, personality-based, and perceptual dehumanization. We hypothesized that testosterone would increase dehumanization, especially for men who watched the "sexualized-clothing" video. Instead, we found that, while men engaged in emotion-based dehumanization toward the sexualized woman both when they had testosterone and placebo, testosterone increased emotion-based dehumanization toward the conservatively dressed woman. Other forms of dehumanization were not affected by testosterone. We also explored whether personality (e.g., dominance) and biological (e.g., CAG repeat polymorphism) traits that have been found to moderate the effects of testosterone on some social behaviors also moderated the effects examined here, but we did not find any significant moderations. Overall, this experiment revealed a novel physiological mechanism affecting emotion-based dehumanization.

Intranasal delivery of imaging agents to the brain.

The potential of intranasal administered imaging agents to altogether bypass the blood-brain barrier offers a promising non-invasive approach for delivery directly to the brain. This review provides a comprehensive analysis of the advancements and challenges of delivering neuroimaging agents to the brain by way of the intranasal route, focusing on the various imaging modalities and their applications in central nervous system diagnostics and therapeutics. The various imaging modalities provide distinct insights into the pharmacokinetics, biodistribution, and specific interactions of imaging agents within the brain, facilitated by the use of tailored tracers and contrast agents. Methods: A comprehensive literature search spanned PubMed, Scopus, Embase, and Web of Science, covering publications from 1989 to 2024 inclusive. Starting with advancements in tracer development, we going to explore the rationale for integration of imaging techniques, and the critical role novel formulations such as nanoparticles, nano- and micro-emulsions in enhancing imaging agent delivery and visualisation. Results: The review highlights the use of innovative formulations in improving intranasal administration of neuroimaging agents, showcasing their ability to navigate the complex anatomical and physiological barriers of the nose-to-brain pathway. Various imaging techniques, MRI, PET, SPECT, CT, FUS and OI, were evaluated for their effectiveness in tracking these agents. The findings indicate significant improvements in brain targeting efficiency, rapid uptake, and sustained brain presence using innovative formulations. Conclusion: Future directions involve the development of optimised tracers tailored for intranasal administration, the potential of multimodal imaging approaches, and the implications of these advancements for diagnosing and treating neurological disorders.

Comparison of intranasal ketamine with intranasal midazolam and dexmedetomidine combination in pediatric dental patients for procedural sedation: A crossover study.

BACKGROUND: The main goal of the pediatric dentist is to address and reduce children's fear and anxiety during the dental treatment, especially when conventional behavior-guiding strategies fail. In such cases, the use of pharmacological agents becomes an essential factor to consider. OBJECTIVE: The objective of the study was to compare the efficacy, safety, and acceptability of intranasal ketamine (INK) with the combination of intranasal midazolam and dexmedetomidine (INMzD) in pediatric dental patients for the procedural sedation. PATIENTS AND METHODS: Forty-seven children aged 3-9 years who required dental procedures such as extractions, pulpectomy, and restorations were randomly distributed into two groups using the envelope drawing method. Group INK received 7 mg/kg INK, whereas Group INMzD received a combination of midazolam spray (0.3 mg/kg) and atomized dexmedetomidine (3 µg/kg). RESULTS: INK showed faster onset, faster recovery, and shorter discharge time than INMzD. Both groups had acceptable physiological parameters and no postoperative complications. INK was more accepted by the patients than INMzD. CONCLUSIONS: In terms of efficacy, safety, and acceptability, INK outperformed the combination of INMzD for the procedural sedation.

PLGA Nanoparticles Based Mucoadhesive Nasal In Situ Gel for Enhanced Brain Delivery of Topiramate.

Oral Topiramate therapy is associated with systemic adverse effects including paresthesia,abdominal pain, and fluctuations in plasma levels. The purpose of this research was to develop an intranasal in situ gel based system comprising Topiramate polymeric nanoparticles and evaluate its potential both in vitro and in vivo. Poly (lactic-co-glycolic acid) (PLGA)nanoparticles prepared by nanoprecipitation method were added into the in situ gelling system of Poloxamer 407 and HPMC K4M. Selected formulation (TG5) was evaluated for physicochemical properties, nasal permeation and in vivo pharmacokinetics in rats. PLGAnanoparticles (O1) exhibited low particle size (~ 144.4 nm), good polydispersity index (0.202), negative zeta potential (-12.7 mV), and adequate entrapment efficiency (64.7%). Developed in situ gel showed ideal pH (6.5), good gelling time (35 s), gelling temperature(37℃), suitable viscosity (1335 cP)and drug content of 96.2%. In vitro drug release conformedto Higuchi release kinetics, exhibiting a biphasic pattern of initial burst release and sustained release for 24 h. Oral administration of the drug to Sprague-Dawley rats (G3) showed higher plasma Cmax(504 ng/ml, p < 0.0001) when compared to nasal delivery of in situ gel (G4) or solution (G5). Additionally, AUC0-α of G3 (8786.82 ng/ml*h) was considerably higher than othergroups. Brain uptake data indicates a higher drug level with G4 (112.47 ng /ml) at 12 h when compared to G3. Histopathological examination of groups; G1 (intranasal saline), G2(intranasal placebo), G3, G4, and G5 did not show any lesions of pathological significance. Overall, the experimental results observed were promising and substantiated the potential of developed in situ gel for intranasal delivery.

Use of intranasal and sublingual analgesia in children and adolescents in the paediatric emergency department.

BACKGROUND: Despite evidence showing that the intranasal and sublingual routes are safe and effective in providing analgesia, no data are available about their day-to-day use in the emergency department (ED). The aim of this study was to assess the frequency of the use of the intranasal and sublingual routes, and the clinical characteristics of the patients receiving analgesia through these routes. METHODS: A multicentre study was performed in the EDs participating in the Pain in Paediatric Emergency Room research group. It included a survey and a retrospective data collection in which the medical records of all patients who received analgesia from 1 April 2022 to 31 May 2022 were collected. RESULTS: 48 centres (91%) answered the survey. The intranasal and sublingual routes were used in 25 centres (52%). 13 centres (27%) used both routes, 9 centres (19%) used only the sublingual and 3 centres (6%) used only the intranasal route.12 centres (48%) participated in the retrospective study. Data about 3409 patients, median age 9 years (IQR 5-12), were collected. Among them, 337 patients (9.6%) received sublingual analgesia, and 87 patients (2.5%) received intranasal analgesia. The intranasal route was employed for injuries in 79 (90.8%) cases, and fentanyl was the drug delivered in 85 (97.7%) cases. The sublingual route was used mainly for injuries (57.3%), but also for abdominal pain (15.4%), musculoskeletal pain (14.5%) and headache (10.7%). Paracetamol, ketorolac and tramadol were administered through this route. CONCLUSIONS: The use of the intranasal and sublingual routes for analgesia in the paediatric ED is still limited.

Intranasal HD-Ad-FS vaccine induces systemic and airway mucosal immunities against SARS-CoV-2 and systemic immunity against SARS-CoV-2 variants in mice and hamsters.

The outbreak of coronavirus disease 19 (COVID-19) has highlighted the demand for vaccines that are safe and effective in inducing systemic and airway mucosal immunity against the aerosol transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study, we developed a novel helper-dependent adenoviral vector-based COVID-19 mucosal vaccine encoding a full-length SARS-CoV-2 spike protein (HD-Ad-FS). Through intranasal immunization (single-dose and prime-boost regimens), we demonstrated that the HD-Ad-FS was immunogenic and elicited potent systemic and airway mucosal protection in BALB/c mice, transgenic ACE2 (hACE2) mice, and hamsters. We detected high titers of neutralizing antibodies (NAbs) in sera and bronchoalveolar lavages (BALs) in the vaccinated animals. High levels of spike-specific secretory IgA (sIgA) and IgG were induced in the airway of the vaccinated animals. The single-dose HD-Ad-FS elicited a strong immune response and protected animals from SARS-CoV-2 infection. In addition, the prime-boost vaccination induced cross-reactive serum NAbs against variants of concern (VOCs; Beta, Delta, and Omicron). After challenge, VOC infectious viral particles were at undetectable or minimal levels in the lower airway. Our findings highlight the potential of airway delivery of HD-Ad-FS as a safe and effective vaccine platform for generating mucosal protection against SARS-CoV-2 and its VOCs.

Harnessing the potential of the NALT and BALT as targets for immunomodulation using engineering strategies to enhance mucosal uptake.

Mucosal barrier tissues and their mucosal associated lymphoid tissues (MALT) are attractive targets for vaccines and immunotherapies due to their roles in both priming and regulating adaptive immune responses. The upper and lower respiratory mucosae, in particular, possess unique properties: a vast surface area responsible for frontline protection against inhaled pathogens but also simultaneous tight regulation of homeostasis against a continuous backdrop of non-pathogenic antigen exposure. Within the upper and lower respiratory tract, the nasal and bronchial associated lymphoid tissues (NALT and BALT, respectively) are key sites where antigen-specific immune responses are orchestrated against inhaled antigens, serving as critical training grounds for adaptive immunity. Many infectious diseases are transmitted via respiratory mucosal sites, highlighting the need for vaccines that can activate resident frontline immune protection in these tissues to block infection. While traditional parenteral vaccines that are injected tend to elicit weak immunity in mucosal tissues, mucosal vaccines (i.e., that are administered intranasally) are capable of eliciting both systemic and mucosal immunity in tandem by initiating immune responses in the MALT. In contrast, administering antigen to mucosal tissues in the absence of adjuvant or costimulatory signals can instead induce antigen-specific tolerance by exploiting regulatory mechanisms inherent to MALT, holding potential for mucosal immunotherapies to treat autoimmunity. Yet despite being well motivated by mucosal biology, development of both mucosal subunit vaccines and immunotherapies has historically been plagued by poor drug delivery across mucosal barriers, resulting in weak efficacy, short-lived responses, and to-date a lack of clinical translation. Development of engineering strategies that can overcome barriers to mucosal delivery are thus critical for translation of mucosal subunit vaccines and immunotherapies. This review covers engineering strategies to enhance mucosal uptake via active targeting and passive transport mechanisms, with a parallel focus on mechanisms of immune activation and regulation in the respiratory mucosa. By combining engineering strategies for enhanced mucosal delivery with a better understanding of immune mechanisms in the NALT and BALT, we hope to illustrate the potential of these mucosal sites as targets for immunomodulation.

Mucoadhesive in situ nasal gel of amoxicillin trihydrate for improved local delivery: Ex vivo mucosal permeation and retention studies.

Orally administered amoxicillin is recommended as the first-line treatment of acute bacterial rhinosinusitis (ABR) and given in a high-dose regimen. However, the risk of various systemic adverse reactions and low oral bioavailability are unbearable, increasing the threat of antibiotic resistance. Therefore, nasal delivery of amoxicillin can be a potential approach for effectively treating ABR locally, as well as overcoming those drawbacks. In a way to guarantee the effectiveness for local therapy in nasal cavity, the permeation and retention properties are of significant importance considerations. Accordingly, the present work aimed to investigate the characteristics with respect to the nasal applicability of the in situ gelling amoxicillin trihydrate (AMT) and further evaluate its permeability and retention properties through human nasal mucosa. The lyophilized formulations were characterized utilizing the Differential Scanning Calorimetry (DSC) and X-ray Powder Diffraction (XRPD), and also evaluated for its polarity, reconstitution time, droplet size distribution, mucoadhesive properties, and ex vivo permeability and retention studies. The results confirmed that the in situ gelling AMT formulations possess adequate mucoadhesive behavior, especially the formulation containing 0.3 % of gellan gum. Substantially, the in situ gelling AMT formulations were able to retain the drug on the surface of nasal mucosa instead of permeating across the membrane; thus, suitable for treating nasal infections locally. Altogether, the in situ gelling systems demonstrates promising abilities as a delivery platform to enhance local application of AMT within the nasal cavity.

An intranasal cationic liposomal polysaccharide vaccine elicits humoral immune responses against Streptococcus pneumoniae.

Diseases caused by S. pneumoniae are the leading cause of child mortality. As antibiotic resistance of S. pneumoniae is rising, vaccination remains the most recommended solution. However, the existing pneumococcal polysaccharides vaccine (Pneumovax® 23) proved only to induce T-independent immunity, and strict cold chain dependence of the protein conjugate vaccine impedes its promotion in developing countries, where infections are most problematic. Affordable and efficient vaccines against pneumococcus are therefore in high demand. Here, we present an intranasal vaccine Lipo+CPS12F&αGC, containing the capsular polysaccharides of S. pneumoniae 12F and the iNKT agonist α-galactosylceramide in cationic liposomes. In BALB/cJRj mice, the vaccine effectively activates iNKT cells and promotes B cells maturation, stimulates affinity-matured IgA and IgG production in both the respiratory tract and systemic blood, and displays sufficient protection both in vivo and in vitro. The designed vaccine is a promising, cost-effective solution against pneumococcus, which can be expanded to cover more serotypes and pathogens.

Syncope after live attenuated influenza vaccine: Reports to the Vaccine Adverse Event Reporting System (2003-2024).

Vasovagal syncope, or fainting, can be triggered by various stimuli, including medical procedures. Syncope after vaccination has been reported, most commonly among adolescents, and can result in injuries. Using the Vaccine Adverse Event Reporting System (VAERS), we reviewed and summarized reports of syncope after live attenuated influenza vaccine, intranasal (LAIV) administered as the sole vaccine (i.e., no concomitant injections). From June 17, 2003 (date of LAIV licensure in the US) through May 31, 2024, VAERS received 50 reports of syncope after LAIV. Nearly half (23; 46 %) pertained to individuals 10-19 years of age. While the vast majority of reports (35; 70 %) did not describe any injuries, 15 people (30 %) were injured, most commonly by falling and hitting their head or face. Twenty-two people (44 %) required evaluation in the emergency department or doctor's office, including an individual who lost consciousness while he was driving home from the vaccination appointment. He did not report any injuries, but the car was severely damaged. Nearly three-quarters of people (37; 74 %) developed syncope within 15 min after vaccination, but fewer than half of reports (24; 48 %) stated that the patient had waited in the observation area for at 15 min. Based on approximately 111.9 million doses of LAIV distributed in the US during the same time period, the reporting rate is approximately 0.4 per million doses, suggesting that syncope following LAIV is rare. The information summarized here may enable clinicians, patients, and caregivers to make a more informed decision regarding preventing injuries that may occur following LAIV-related syncope.