Nasal Lavage Research Articles

Identification and characterization of microplastics in nasal irrigation fluids: A preliminary study.

Microplastics were identified in nasal irrigations Polypropylenes, which were the main component of the nozzle, were commonly identified Additional studies are needed to understand the biological relevance of microplastics in nasal irrigations.

Mucosal SARS-CoV-2 Nanoparticle Vaccine Based on Mucosal Adjuvants and Its Immune Effectiveness by Intranasal Administration.

SARS-CoV-2 is a respiratory virus that causes significant threats to human health. Mucosal immunity provides a first-line defense to prevent the infection of SARS-CoV-2 in the respiratory tract. Because most SARS-CoV-2 vaccines could not stimulate mucosal immunity in the respiratory tract, appropriate mucosal adjuvants or delivery systems are needed for mucosal vaccine development. Mannan, polyarginine, and 2',3'-cGAMP are three mucosal adjuvants that could stimulate mucosal immunity. In the present study, the three adjuvants were assembled with a receptor-binding domain (RBD) by electrostatic interaction to generate a nanoparticle vaccine (RBD-MP-cG). RBD-MP-cG elicited mucosal IgA and IgG response in bronchoalveolar lavage and nasal lavage by intranasal administration. It induced a robust RBD-specific antibody response, high levels of protective neutralizing antibody, and ACE2-blocking activity in the mouse sera. It stimulated the splenic secretion of high levels of Th1-, Th2-, and Th17-type cytokines. Thus, RBD-MP-cG elicited strong mucosal immunity and systematic immunity by intranasal administration. RBD-MP-cG was expected to act as a safe, effective, and easily produced mucosal nanoparticle vaccine to combat the infection of SARS-CoV-2.

Comparison of intranasal medication delivery devices before and after functional endoscopic sinus surgery using Phacon sinus surgery models.

Functional endoscopic sinus surgery for chronic rhinosinusitis improves sinus drainage and intranasal medication delivery. This study compares medication delivery with commonly used devices in normal and altered anatomy (post functional endoscopic sinus surgery) using sinus surgery models (Phacon). Medication delivery was simulated via nasal drops, nasal spray and an irrigation device (Neilmed Sinus Rinse). Coverage was then calculated from endoscopic pictures taken at various anatomical sites in the normal nose and post functional endoscopic sinus surgery. In the normal nose, nasal spray did not penetrate the sphenoid sinus, and drops bypassed the vestibule anteriorly. Neilmed Sinus Rinse provided superior coverage at the sphenoid site following sphenoidectomy and the frontal site following Draf III. After ethmoidectomy, nasal drops overall provided less coverage than the other methods. Neilmed Sinus Rinse generally provided the best distribution, followed by the nasal spray and then nasal drops. The type and extent of surgery also affects medication delivery.

Development and Dynamic Responsiveness of the Acute Asthma Exacerbation Survey in Patients With Moderate to Severe Disease

The recall periods and response scales of existing surveys of asthma control are poorly suited for studying acute exacerbations. To develop an instrument able to predict exacerbations after the onset of acute symptoms and with a recall window sufficiently short to study recovery. We developed the six-item Acute Asthma Exacerbation Survey (AAES). Data were collected at baseline, acute, and recovery visits within an established longitudinal protocol for participants with severe asthma. Participants scheduled acute study visits at the first sign of a cold. Nasal lavage samples and lung function measurements were also collected. The AAES data were analyzed using Cronbach α, Spearman correlations, and Kruskal-Wallace methods. We used logistic regression for predictors of bursts of oral corticosteroids (OCS). Of 130 participants studied at baseline, 52 returned for an acute visit. The AAES scores were elevated at the acute visit and returned to baseline after recovery independently of respiratory virus detection. Cronbach α for the AAES was 0.853, 0.822, and 0.889 at the three respective visits. Compared with participants not needing burst OCS, those with exacerbations had higher acute AAES scores (16 [13.5-18] vs 11.5 [8.2-14], median [interquartile range];P= .017) and a larger reduction from baseline in lung function. For each 3-point increase in AAES scores, the odds ratio for burst OCS use was 1.64 (95% CI, 1.04-2.57; P= .030). The AAES is internally consistent and dynamically responsive during acute asthma exacerbations. Additional validation studies are warranted to support future trials and aid in clinical decision-making.

Airway and systemic biomarkers of health effects after short-term exposure to indoor ultrafine particles from cooking and candles – A randomized controlled double-blind crossover study among mild asthmatic subjects

BackgroundThere is insufficient knowledge about the systemic health effects of exposure to fine (PM2.5) and ultrafine particles emitted from typical indoor sources, including cooking and candlelight burning. We examined whether short-term exposure to emissions from cooking and burning candles cause inflammatory changes in young individuals with mild asthma. Thirty-six non-smoking asthmatics participated in a randomized controlled double-blind crossover study attending three exposure sessions (mean PM2.5 µg/m3; polycyclic aromatic hydrocarbons ng/m3): (a) air mixed with emissions from cooking (96.1; 1.1), (b) air mixed with emissions from candles (89.8; 10), and (c) clean filtered air (5.8; 1.0). Emissions were generated in an adjacent chamber and let into a full-scale exposure chamber where participants were exposed for five hours. Several biomarkers were assessed in relation to airway and systemic inflammatory changes; the primary outcomes of interest were surfactant Protein-A (SP-A) and albumin in droplets in exhaled air – novel biomarkers for changes in the surfactant composition of small airways. Secondary outcomes included cytokines in nasal lavage, cytokines, C-reactive protein (CRP), epithelial progenitor cells (EPCs), genotoxicity, gene expression related to DNA-repair, oxidative stress, and inflammation, as well as metabolites in blood. Samples were collected before exposure start, right after exposure and the next morning.ResultsSP-A in droplets in exhaled air showed stable concentrations following candle exposure, while concentrations decreased following cooking and clean air exposure. Albumin in droplets in exhaled air increased following exposure to cooking and candles compared to clean air exposure, although not significant. Oxidatively damaged DNA and concentrations of some lipids and lipoproteins in the blood increased significantly following exposure to cooking. We found no or weak associations between cooking and candle exposure and systemic inflammation biomarkers including cytokines, CRP, and EPCs.ConclusionsCooking and candle emissions induced effects on some of the examined health-related biomarkers, while no effect was observed in others; Oxidatively damaged DNA and concentrations of lipids and lipoproteins were increased in blood after exposure to cooking, while both cooking and candle emissions slightly affected the small airways including the primary outcomes SP-A and albumin. We found only weak associations between the exposures and systemic inflammatory biomarkers. Together, the results show the existence of mild inflammation following cooking and candle exposure.

Detection of microplastics in patients with allergic rhinitis.

We aimed to investigate the relationship between microplastics, which are a worldwide health and environmental issue, and their relationship to allergic rhinitis. A total of 66 patients participated in this prospective study. The patients were divided into two groups. While there were 36 patients with allergic rhinitis in group 1, there were 30 healthy volunteers in group 2. The participants' age, gender and Score for Allergic Rhinitis results were noted. Microplastics were examined in the nasal lavage fluids of the patients and their numbers noted. The groups were compared on these values. There was no significant difference between the groups in terms of age and gender. There was a significant difference between the allergic rhinitis group and the control group in terms of the Score for Allergic Rhinitis results (p < 0.001). In the allergic rhinitis group, the microplastic density in the nasal lavage was significantly higher than in the control group (p = 0.027). Microplastics were detected in all participants. We found more microplastics in allergic rhinitis patients. According to this result, we can say that there is a relationship between allergic rhinitis and microplastics.

A Hypertonic Seawater Nasal Irrigation Solution Containing Algal and Herbal Natural Ingredients Reduces Viral Load and SARS-CoV-2 Detection Time in the Nasal Cavity.

Nasal irrigation is thought to decrease the viral load present in the nasal cavity. Our aim was to assess the effect of a hypertonic seawater solution [with algal and herbal natural ingredients (Sinomarin®)] on the viral load of nasopharynx in patients hospitalized with severe COVID-19 pneumonia. We conducted a prospective, randomized, controlled trial from June 2022 to December 2022. We allocated 56 patients with COVID-19 pneumonia into two groups (28 in each group)-the hypertonic seawater group [nasal irrigations with a hypertonic seawater solution (Sinomarin®) every 4 h for 16 h per day, for two consecutive days] and the control group (no nasal irrigations). A second nasopharyngeal swab was collected 48 h after the baseline nasopharyngeal swab (8 h after the last wash in the hypertonic seawater group) to estimate the SARS-CoV-2 viral load as determined by cycle threshold (Ct) values. In the hypertonic seawater group, the mean Ct values significantly increased two days after the initial measurement [ΔCt 48-0 h = 3.86 ± 3.03 cycles, p < 0.001 (95%CI: 2.69 to 5.04)]. No significant differences in the Ct values were observed in the control group [ΔCt 48-0 h = -0.14 ± 4.29, p = 0.866 (95%CI: -1.80 to -1.52)]. At follow-up, 17 patients from the hypertonic seawater group had negative test results compared to only 9 patients from the control group (p = 0.03). Nasal irrigations with a hypertonic seawater solution containing algal and herbal natural ingredients significantly decreased nasopharyngeal viral load and the detection time of SARS-CoV-2 in the nasal cavity.

Myricetin alleviates ovalbumin-induced allergic rhinitis in mice by regulating Th1/Th2 balance

Objective: To evaluate the effect of myricetin on ovalbumin (OVA)-induced allergic rhinitis in mice. Methods: Mice were sensitized and challenged using OVA (5%, 500 mL) intraperitoneally and intranasally, respectively, on an alternative day for 14 days, followed by administration of myricetin (50, 100, and 200 mg/kg) till day 21. Nasal symptoms, biochemical parameters, protein expressions, and histopathology were observed. Results: OVA-induced increased nasal symptoms including rubbing, sneezing, and discharge were significantly reduced by myricetin (100 and 200 mg/kg) (P&lt;0.05). Myricetin also protected against histamine challenge and attenuated elevated serum immunoglobulin E (IgE; total and OVA-specific), total IgG1, and β-hexosaminidase levels, as well as leukotriene C4 and interleukins levels in nasal lavage fluid (P&lt;0.05). Western blot analysis showed that myricetin significantly upregulated the protein expression of T-box expressed in T cells, while downregulating the protein expression of GATA binding protein 3, NF-κB, and 1κВ-α (P&lt;0.05). Additionally, OVA-induced histopathological abberations in the nasal mucosa was markedly ameliorated by myricetin treatment (P&lt;0.05). Conclusions: Myricetin exerts anti-allergic effects against OVA-induced allergic rhinitis via regulating Th1/Th2 balance.

Intranasal VLP-RBD vaccine adjuvanted with BECC470 confers immunity against Delta SARS-CoV-2 challenge in K18-hACE2-mice

As the COVID-19 pandemic transitions into endemicity, seasonal boosters are a plausible reality across the globe. We hypothesize that intranasal vaccines can provide better protection against asymptomatic infections and more transmissible variants of SARS-CoV-2. To formulate a protective intranasal vaccine, we utilized a VLP-based platform. Hepatitis B surface antigen-based virus like particles (VLP) linked with receptor binding domain (RBD) antigen were paired with the TLR4-based agonist adjuvant, BECC 470. K18-hACE2 mice were primed and boosted at four-week intervals with either VLP-RBD-BECC or mRNA-1273. Both VLP-RBD-BECC and mRNA-1273 vaccination resulted in production of RBD-specific IgA antibodies in serum. RBD-specific IgA was also detected in the nasal wash and lung supernatants and were highest in VLP-RBD-BECC vaccinated mice. Interestingly, VLP-RBD-BECC vaccinated mice showed slightly lower levels of pre-challenge IgG responses, decreased RBD-ACE2 binding inhibition, and lower neutralizing activity in vitro than mRNA-1273 vaccinated mice. Both VLP-RBD-BECC and mRNA-1273 vaccinated mice were protected against challenge with a lethal dose of Delta variant SARS-CoV-2. Both vaccines limited viral replication and viral RNA burden in the lungs of mice. CXCL10 is a biomarker of severe SARS-CoV-2 infection and we observed both vaccines limited expression of serum and lung CXCL10. Strikingly, VLP-RBD-BECC when administered intranasally, limited lung inflammation at early timepoints that mRNA-1273 vaccination did not. VLP-RBD-BECC immunization elicited antibodies that do recognize SARS-CoV-2 Omicron variant. However, VLP-RBD-BECC immunized mice were protected from Omicron challenge with low viral burden. Conversely, mRNA-1273 immunized mice had low to no detectable virus in the lungs at day 2. Together, these data suggest that VLP-based vaccines paired with BECC adjuvant can be used to induce protective mucosal and systemic responses against SARS-CoV-2.

Effect of nasal irrigation on eosinophil and recurrence in allergic rhinitis

Until now, the treatment of allergic rhinitis has not been satisfactory. Patients with allergic rhinitis are highly dependent on medical pharmacological treatment. Nasal irrigation is expected to help reduce symptoms due to decreased eosinophil counts and recurrence of allergic rhinitis. This study aims to determine the effect of nasal irrigation on eosinophils and the recurrence of allergic rhinitis—experimental research by pre – post-test group design. Twenty samples of allergic rhinitis patients were trained to wash their nose once a day at home—nasal mucosal secretion was collected to count eosinophils before and after intervention. The degree of recurrence was assessed based on the symptoms of nasal congestion, runny nose, sneezing, and itchy nose. The degree is divided into three groups: decrease, remain, and increase. The statistical analysis used in this study for bivariate analysis was Wilcoxon Test. There was a significant decrease in eosinophil count (p = 0.00) and recurrence of nasal congestion (p = 0.00), runny nose (p = 0.00), sneezing (p = 0.001) and itchy nose (p = 0.00) in allergic rhinitis after nasal irrigation intervention. Nasal irrigation treatment can help decrease eosinophil count and recurrence of allergic rhinitis.

Immunological efficacy of cavitated solutions in the complex therapy of chronic rhinitis

Quantitative and qualitative indicators of nasal lavages in patients with chronic rhinitis have been studied. The results of the study have shown that an increase in the number of viable neutrophilic granulocytes and in their lysosomal activity, a decrease in the activity and intensity of phagocytosis, inhibition of biocidal properties according to the spontaneous HCT test, and a decrease in the content of secretory IgA are recorded in patients with chronic rhinitis. The use of a 0.9 % sodium chloride cavitated solution led to the restoration of quantitative and qualitative indicators of innate immunity and some indicators of adaptive immunity in patients’ nasal secretions.

Genome-wide DNA methylation sequencing identifies epigenetic perturbations in the upper airways under long-term exposure to moderate levels of ambient air pollution

While the link between exposure to high levels of ambient particulate matter (PM) and increased incidences of respiratory and cardiovascular diseases is widely recognized, recent epidemiological studies have shown that low PM concentrations are equally associated with adverse health effects. As DNA methylation is one of the main mechanisms by which cells regulate and stabilize gene expression, changes in the methylome could constitute early indicators of dysregulated signaling pathways. So far, little is known about PM-associated DNA methylation changes in the upper airways, the first point of contact between airborne pollutants and the human body. Here, we focused on cells of the upper respiratory tract and assessed their genome-wide DNA methylation pattern to explore exposure-associated early regulatory changes. Using a mobile epidemiological laboratory, nasal lavage samples were collected from a cohort of 60 adults that lived in districts with records of low (Simmerath) or moderate (Stuttgart) PM10 levels in Germany. PM10 concentrations were verified by particle measurements on the days of the sample collection and genome-wide DNA methylation was determined by enzymatic methyl sequencing at single-base resolution. We identified 231 differentially methylated regions (DMRs) between moderately and lowly PM10 exposed individuals. A high proportion of DMRs overlapped with regulatory elements, and DMR target genes were involved in pathways regulating cellular redox homeostasis and immune response. In addition, we found distinct changes in DNA methylation of the HOXA gene cluster whose methylation levels have previously been linked to air pollution exposure but also to carcinogenesis in several instances. The findings of this study suggest that regulatory changes in upper airway cells occur at PM10 levels below current European thresholds, some of which may be involved in the development of air pollution-related diseases.

Effect of Nasal Irrigation in Children With Omicron Variant of COVID-19 Infection.

Objective: To explore the effect of nasal irrigation on the disappearance of symptoms and nucleic acid conversion in children with Omicron variant. Methods: This quasi-experimental study included children diagnosed with asymptomatic, mild, and moderate Omicron variant infection during the isolation observation period in the Shandong Public Health Clinical Center between April 1, 2022 and May 1, 2022. The children were divided into a routine group (received Lianhua Qingwen (LhQw) Granules), isotonic saline group (received LhQw Granules combined with isotonic saline nasal irrigation), and hypertonic saline group (received LhQw Granules combined with 3% hypertonic saline nasal irrigation), respectively. The primary outcomes were the time of symptom disappearance and nucleic acid conversion time. The secondary outcomes were peripheral white blood cell count (WBC), lymphocyte count (LYM), neutrophil count (NEU), and C-reactive protein (CRP) levels. Results: A total of 60 children (7.26 ± 3.15years old) were included (20 per group). The average time of nucleic acid conversion in the 2 saline nasal irrigation groups was significantly reduced compared with the routine group (all P < 0.001), while the fever time and cough duration among the 3 groups were comparable (all P > 0.05). LYM count in the 2 saline nasal irrigation groups was significantly increased after treatment compared to before treatment and was significantly higher than in the routine group (all P < 0.05). There was no significant difference in LYM count between the isotonic and hypertonic saline groups (P = 0.76). Additionally, all children in the saline group well tolerated the treatment, and no adverse events occurred in the isotonic saline group. Conclusions: Timely use of saline nasal irrigation may promote nucleic acid conversion in children with Omicron virus infection.

Saline nasal irrigation and gargling in COVID-19: a multidisciplinary review of effects on viral load, mucosal dynamics, and patient outcomes.

With unrelenting SARS-CoV-2 variants, additional COVID-19 mitigation strategies are needed. Oral and nasal saline irrigation (SI) is a traditional approach for respiratory infections/diseases. As a multidisciplinary network with expertise/experience with saline, we conducted a narrative review to examine mechanisms of action and clinical outcomes associated with nasal SI, gargling, spray, or nebulization in COVID-19. SI was found to reduce SARS-CoV-2 nasopharyngeal loads and hasten viral clearance. Other mechanisms may involve inhibition of viral replication, bioaerosol reduction, improved mucociliary clearance, modulation of ENaC, and neutrophil responses. Prophylaxis was documented adjunctive to personal protective equipment. COVID-19 patients experienced significant symptom relief, while overall data suggest lower hospitalization risk. We found no harm and hence recommend SI use, as safe, inexpensive, and easy-to-use hygiene measure, complementary to hand washing or mask-wearing. In view of mainly small studies, large well-controlled or surveillance studies can help to further validate the outcomes and to implement its use.

Validation of a Droplet Digital PCR (ddPCR) Assay to Detect Cyanobacterial 16S rDNA in Human Lung Tissue.

Cyanobacteria produce a variety of secondary metabolites, including toxins that may contribute to the development of disease. Previous work was able to detect the presence of a cyanobacterial marker in human nasal and broncoalveolar lavage samples; however, it was not able to determine the quantification of the marker. To further research the relationship between cyanobacteria and human health, we validated a droplet digital polymerase chain reaction (ddPCR) assay to simultaneously detect the cyanobacterial 16S marker and a human housekeeping gene in human lung tissue samples. The ability to detect cyanobacteria in human samples will allow further research into the role cyanobacteria plays in human health and disease.

Do variations in nasal irrigation recipes and storage effect the risk of bacterial contamination? - ERRATUM.

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Histamine-releasing factor in severe asthma and rhinovirus-associated asthma exacerbation

Histamine-releasing factor (HRF) is implicated in allergic diseases. We previously showed its pathogenic role in murine models of asthma. We aim to present data analysis from 3 separate human samples (sera samples from asthmatic patients, nasal washings from rhinovirus [RV]-infected individuals, and sera samples from patients with RV-induced asthma exacerbation) and 1 mouse sample to investigate correlates of HRF function in asthma and virus-induced asthma exacerbations. Total IgE and HRF-reactive IgE/IgG as well as HRF in sera from patients with mild/moderate asthma or severe asthma (SA) and healthy controls (HCs) were quantified by ELISA. HRF secretion in culture media from RV-infected adenovirus-12 SV40 hybrid virus transformed human bronchial epithelial cells and in nasal washings from experimentally RV-infected subjects was analyzed by Western blotting. HRF-reactive IgE/IgG levels in longitudinal serum samples from patients with asthma exacerbations were also quantified. HRF-reactive IgE and total IgE levels were higher in patients with SA than in HCs, whereas HRF-reactive IgG (and IgG1) level was lower in asthmatic patients versus HCs. In comparison with HRF-reactive IgElow asthmatic patients, HRF-reactive IgEhigh asthmatic patients had a tendency to release more tryptase and prostaglandin D2 on anti-IgE stimulation of bronchoalveolar lavage cells. RV infection induced HRF secretion from adenovirus-12 SV40 hybrid virus transformed bronchial epithelial cells, and intranasal RV infection of human subjects induced increased HRF secretion in nasal washes. Asthmatic patients had higher levels of HRF-reactive IgE at the time of asthma exacerbations associated with RV infection, compared with those after the resolution. This phenomenon was not seen in asthma exacerbations without viral infections. HRF-reactive IgE is higher in patients with SA. RV infection induces HRF secretion from respiratory epithelial cells both invitro and invivo. These results suggest the role of HRF in asthma severity and RV-induced asthma exacerbation.

Schistosoma japonicum-derived peptide SJMHE1 ameliorates allergic symptoms and responses in mice with allergic rhinitis.

Helminth derived excretory/secretory molecules have shown efficacy in the treatment of allergic asthma in mice, but their roles in allergic rhinitis (AR) are little known. In this study, we aimed to determine the intervention effect of SJMHE1, a Schistosoma japonicum derived small molecular peptide, on ovalbumin (OVA)-induced AR mice and investigate its possible mechanism. AR was induced in BALB/c mice, following which the mice were treated with phosphate-buffered saline (PBS), OVA323-339 and SJMHE1 respectively. SJMHE1 treatment improved clinical symptoms (rubbing and sneezing), suppressed infiltrates of inflammatory cells and eosinophils in nasal mucosa, modulated the production of type-2 (IL-4 and IL-13) and anti-inflammatory (IL-10) cytokines in the nasal lavage fluids (NLF), spleen, and serum. To investigate the underlying mechanism, fluorescein isothiocyanate (FITC)-labeled SJMHE1 was subcutaneously injected into AR mice, and we found that the FITC-SJMHE1 could accumulate in spleen, but not in nasal mucosa. FITC-SJMHE1 mainly bound to CD19 positive cells (B cells), and the SJMHE1 treatment significantly increased the proportion of regulatory B cells (Bregs) and B10 cells, along with the enhancement of PR domain containing protein 1 (Prdm1) protein levels. SJMHE1 may alleviate AR by upregulating Bregs, and has great potential as a new avenue for the AR treatment.

Two MP2CL5 Antigen Vaccines from Naegleria fowleri Stimulate the Immune Response against Meningitis in the BALB/c Model.

Naegleria fowleri is an etiological agent that generates primary amoebic meningoencephalitis; unfortunately, no effective treatment or vaccine is available. The objective of this work was to determine the immunoprotective response of two vaccine antigens, as follows: (i) the polypeptide band of 19 kDa or (ii) a predicted immunogenic peptide from the membrane protein MP2CL5 (Smp145). Both antigens were administered intranasally in mice using cholera toxin (CT) as an adjuvant. The survival rate and immune response of immunized mice with both antigens and challenged with N. fowleri trophozoites were measured in the nose-associated lymphoid tissue (NALT) and nasal passages (NPs) by flow cytometry and enzyme-linked immunosorbent assay (ELISA). We also determined the immunolocalization of both antigens in N. fowleri trophozoites by confocal microscopy. Immunization with the polypeptide band of 19 kDa alone or coadministered with CT was able to confer 80% and 100% of protection, respectively. The immunization with both antigens (alone or coadministered with CT) showed an increase in T and B lymphocytes. In addition, there was an increase in the expression of integrin α4β1 and IgA in the nasal cavity of protected mice, and the IgA, IgG, and IgM levels were increased in serum and nasal washes. The immunolocalization of both antigens in N. fowleri trophozoites was observed in the plasma membrane, specifically in pseudopod-like structures. The MP2CL5 antigens evaluated in this work were capable of conferring protection which would lead us to consider them as potential candidates for vaccines against meningitis caused by N. fowleri.

Sublingual prophylactic administration of OVA-loaded MSC-derived exosomes to prevent allergic sensitization

AimThis study evaluated the immunomodulatory and delivery potential of adipose tissue-isolated MSC-derived exosomes as a prophylactic regimen through a sublingual route in the ovalbumin (OVA)-induced allergic asthma murine model. Material and methodsBalb/c mice received 10 μg/dose of OVA-enriched MSC-derived exosomes as a prophylactic regimen in six doses during three weeks, and then OVA sensitization was conducted through intraperitoneal and aerosol administration of allergen. The total cells and eosinophils counted in nasal lavage fluid (NALF) and lung tissues were assessed for histopathological analysis. In addition, the secretion of IFN-γ, IL-4, and TGF-β by spleen cells and serum OVA-specific IgE levels were measured via ELISA. ResultsSignificant reduction in the IgE levels and IL-4 production, along with elevated TGF-β levels, were observed. Also, limited cellular infiltrations and perivascular and peribronchiolar inflammation in the lung tissues and normal total numbers of cells and eosinophils in the NALF were reported. ConclusionProphylactic regimen using OVA-enriched MSC-derived exosomes modulated immune responses and inhibited allergic OVA sensitization.