House dust mite-specific immunotherapy alters the natural course of atopic march

An atopic dermatitis-like murine model by skin-brushed cockroach Per a 2 and oral tolerance induction by Lactococcus lactis-derived Per a 2

Atopic dermatitis (AD) is a complex, chronic inflammatory skin disease. An estimated 57.5% of asthmatic patients and 50.7% of rhinitis patients are allergic to cockroaches in Taiwan. However, the role of cockroaches in the pathogenesis of AD is undetermined. Oral tolerance might be another strategy for protecting against AD and allergic inflammation by regulating T helper 2 (Th2) immune responses. Aim to examine the underlying immunologic mechanism, we developed an AD-like murine model by skin-brushing with cockroach Per a 2. We also investigated whether the systemic inflammation of AD in this murine model could be improved by specific tolerance to Lactococcus lactis-expressing Per a 2, which was administered orally. Repeated painting of Per a 2 without adjuvant to the skin of mice resulted in increased total IgE, Per a 2-specific IgE, and IgG1, but not IgG2a. In addition, epidermal thickening was significantly increased, there were more scratch episodes, and there were increases in total white blood cells (eosinophil, neutrophil, and lymphocyte) and Th2 cytokines (Interleukin (IL)-4, IL-5, IL-9, and IL-13) in a dose-dependent manner. The results revealed that oral administration of L. lactis-Per a 2 ameliorated Per a 2-induced scratch behavior and decreased the production of total IgE, Per a 2-specific IgE, and IgG1. Furthermore, L. lactis-Per a 2 treatment also suppressed inflammatory infiltration, expressions of thymic stromal lymphopoietin (TSLP) and IL-31 in skin lesions, and downregulated splenic IL-4 and IL-13 in Per a 2-induced AD mice. This study provides evidence supporting that repeated brushing of aeroallergens to the skin leads to atopic dermatitis phenotypes and oral allergen-specific immune tolerance can ameliorate AD-like symptoms and systemic inflammation and prevent progression of atopic march.

The Effectiveness of Allergen Immunotherapy in Adult Patients with Atopic Dermatitis Allergic to House Dust Mites

Background and objectives: Allergen immunotherapy (AIT) is not a first-line therapy in atopic dermatitis (AD) and its effectiveness has been criticised. Objectives: The efficacy and safety of AIT in adult patients with AD and monosensitisation to house dust mites (HDMs) were investigated. Materials and Methods: A total of 37 patients were included in this double-blind, placebo-controlled study. Patients were eligible if they were diagnosed with AD; had moderate-to-severe AD according to the Eczema Area and Severity Index (EASI) with at least 7.1 points, the % BSA (body surface area) scale with at least 16 points, and the IsGA (investigator global assessment) scale with 3 points; had positive skin prick tests (SPTs); and were positive for the specific immunoglobulin E (sIgE) response to D. pteronyssinus and D. farinae extracts, as well as Der p 1 and Der f1. The patients received Purethal mites (20,000 AUeq/mL, HAL Allergy, Leiden, The Netherlands) with the extract allergens D. pteronyssinus and D. farinae (50/50%) or a placebo for 12 months. The primary outcomes included changes in EASI, % BSA, and IsGA due to SCIT between the start and after 12 months of therapy. Results: In the study group, significant improvement was observed in terms of the EASI score from 43 ± 8.2 to 21 ± 5.9 points, % BSA from 72 ± 18 to 28 ± 11 points, and IsGA from 4.5 ± 0.5 to 1.5 ± 0.5 points in comparison with the placebo after 1 year of AIT. Additionally, the proportion of patients who achieved success in the IsGA (IsGA < 2) was significantly better in comparison to the placebo with 13/20 (65%) vs. 4/14 (29%), respectively (p < 0.05). Conclusions: HDM-AIT effectively improved atopic dermatitis in patients that strictly qualified for desensitisation with a confirmed monovalent mite allergy.

Efficacy and safety of subcutaneous immunotherapy with a mixture of glutaraldehyde-modified extracts of Dermatophagoides pteronyssinus, Dermatophagoides farinae , and Blomia tropicalis

Background

Allergen Immunotherapy (AIT) is an effective treatment of allergic respiratory diseases induced by the inhalation of house dust mite allergens.

Objectives

To evaluate the efficacy and safety of glutaraldehyde polymerized allergen extracts using a mixture of Dermatophagoides pteronyssinus, D. farinae and Blomia tropicalis in mite allergic individuals residing in Colombia.

Methods

Two hundred and fifty (250) patients with allergic rhinoconjunctivitis with, or without asthma and sensitized to D. pteronyssinus, D. farinae and B. tropicalis were included. A glutaraldehyde-modified extract containing a mixture of D. pteronyssinus, D. farinae and B. tropicalis was employed, using a cluster up-dosing schedule followed by a monthly maintenance dose. The primary endpoints to evaluate the clinical impact were the Combined Symptom and Medication Scores (CSMS) for allergic rhinitis, the Asthma Control Test (ACT) and the reduction in medication consumption.

Results

Significant improvement was found after 3 months of treatment regarding CSMS (p < 0.0001) and ACT (p < 0.0001). Additionally, a significant decrease in medication consumption was found after 3 months of treatment (p < 0.0001). Adverse reactions, either local or systemic were mild and no severe reactions related to the vaccines were observed.

Conclusion

After 12 months of allergen immunotherapy, glutaraldehyde-modified mixture of D. pteronyssinus, D. farinae and B. tropicalis proved to be safe and effective in the treatment of patients with rhinoconjunctivitis with or without asthma due to allergy to mites.

Sublingual immunotherapy for pediatric patients with mite allergies

Sublingual immunotherapy (SLIT) has been increasingly used instead of subcutaneous immunotherapy. SLIT was initially approved for use among adults; however, it has become more widely accepted for children. Few studies have evaluated the effectiveness of SLIT in the treatment of dust mite allergies among children, including adverse effects. This study aimed to investigate the effectiveness of SLIT in children with dust mite allergies, as well as its adverse effects, at a pediatric general outpatient clinic.I analyzed the data of 181 patients aged 4 to 12 years who tested positive for mite antigen-specific immunoglobulin E, exhibited nasal and/or eye symptoms, and received Miticure. Symptoms were evaluated using the Japanese rhino-conjunctivitis quality of life (QOL) questionnaire no. 1. Wilcoxon tests were used to compare the pretreatment and post-treatment symptom scores. Adverse events were tallied, and Kaplan-Meier curves and Wilcoxon tests were used to assess the proportion of dropouts.The mean QOL score at the baseline was 2.17 (standard deviation [SD] 1.45). After 1 week, the mean symptom QOL score was 1.63 (SD 1.32); the lowest mean score was found in week 41 (0.48, SD 0.63). A significant decline in the occurrence of all symptoms, including sneezing, nasal discharge, nasal congestion, itchy eyes, and teary eyes, was observed. Adverse effects were observed in 76 (42.0%) patients; the most common adverse effect was itchy mouth.SLIT improves symptoms with minimal adverse effects in pediatric patients.

Effectiveness and safety of oral lactococci-based vaccine encoding triple common allergens to prevent airway allergy in mice

Allergic airway disease is the most common chronic airway inflammatory disorder in developed countries. House dust mite, cockroach, and mold are the leading allergens in most tropical and subtropical countries, including Taiwan. As allergen avoidance is difficult for patients allergic to these perennial indoor allergens, allergen-specific immunotherapy (ASIT) is the only available allergen-specific and disease-modifying treatment. However, for patients sensitized to multiple allergens, ASIT using each corresponding allergen is cumbersome. In the present study, we developed a recombinant L. lactis vaccine against the three most common indoor aeroallergens and investigated its effectiveness for preventing respiratory allergy and safety in mice. Three recombinant clones of Der p 2 (mite), Per a 2 (roach), and Cla c 14 (mold) were constructed individually in pNZ8149 vector and then electroporated into host strain L.lactis NZ3900. BALB/c mice were fed with the triple vaccine 5 times per week for 4 weeks prior to sensitization. The effectiveness and safety profile were then determined. Oral administration of the triple vaccine significantly alleviated allergen-induced airway hyper-responsiveness in the vaccinated mice. The allergen-specific IgG2a was upregulated. IL-4 and IL-13 mRNA expressions as well as inflammatory cell infiltration in the lungs decreased significantly in the vaccinated groups. No body weight loss or abnormal findings in the liver and kidneys were found in any of the groups of mice. This is the first report to describe a triple-aeroallergen vaccine using a food-grade lactococcal expression system. We developed a convenient oral delivery system and intend to extend this research to develop a vaccination that can be self-administered at home by patients.

Sublingual immunotherapy with Dermatophagoides farinae drops for pediatric atopic dermatitis

BACKGROUND

We evaluated the clinical effect and safety of sublingual immunotherapy (SLIT) with Dermatophagoides farinae drops for pediatric atopic dermatitis (AD).

METHODS

We enrolled children aged 4-13 years with AD and grouped them into the SLIT and control groups using the random number table method. We subdivided each group based on treatment duration (1-, 2-, and 3-year subgroups). The SLIT group received Dermatophagoides farinae drops, and both groups received conventional treatment (topical glucocorticoids, skin moisturizers, oral antihistamines, and allergen avoidance). Effective rate and effect were compared between groups after 1, 2, and 3 years of treatment.

RESULTS

We assessed 309 SLIT cases (male, 192; age, 4-13 years) and 131 controls (male, 79; age 4-13 years). The effective rate and curative effect after 2 and 3 years of treatment were significantly different between the groups (P < 0.05). The effect and effective rates between corresponding SLIT and control group treatment duration subgroups were significantly different (P < 0.05). SLIT group duration subgroups showed significant differences in the effect and effective rates (P < 0.05). Posttreatment Scoring Atopic Dermatitis (SCORAD) scores in the SLIT group duration subgroups were significantly lower than those of the corresponding control subgroups (P < 0.05). Upon follow-up at 1 year post treatment completion, the SLIT group's SCORAD score was significantly lower than its baseline score and the control group's follow-up score (P < 0.05).

CONCLUSION

SLIT with Dermatophagoides farinae drops for pediatric AD is safe and effective; effectiveness is maintained after treatment cessation, and prolonged treatment improves efficacy.

[Systemic reactions to subcutaneous immunotherapy for bronchial asthma and/or allergic rhinitis in children and their risk factors]

OBJECTIVE

To investigate the incidence of systemic reactions (SR) to subcutaneous immunotherapy (SCIT) for bronchial asthma and/or allergic rhinitis in children and their risk factors.

METHODS

A retrospective analysis was performed on 198 children with bronchial and/or allergic rhinitis. According to the presence or absence of SR and local reactions (LR) during SCIT, the patients were divided into two groups: SR (with SR and LR, n=31) and control (without SR or LR, n=142). A multivariate logistic regression analysis was used to determine the risk factors associated with SR.

RESULTS

Among the 198 patients who received 8 157 injections of SCIT, 25 (12.6%) experienced SR (31 times, 0.38%), including grade I SR (18 times, 58%), grade II SR (10 times, 32%), grade III SR (3 times, 10%), and no grade IV SR. The multivariate logistic regression analysis showed that multiple sensitization with both food and inhaled allergens, specific IgE to dust mites (grade 6), total IgE (grade 6), and a history of LR were independent risk factors for SR (P<0.05).

CONCLUSIONS

SCIT is a safe treatment for bronchial asthma and/or allergic rhinitis in children, with a low incidence of SR. Children with multiple sensitization with both food and inhaled allergens, a hypersensitive state (specific IgE to dust mites, grade 6; total IgE, grade 6), and a history of LR have an increased risk of SR to SCIT.

Allergen Immunotherapy in Pediatric Asthma: A Pragmatic Point of View

To date, the only disease-modifying treatment strategy for allergic rhinitis and asthma is allergen immunotherapy (AIT). There is evidence that AIT improves allergic rhinitis and asthma, such as reducing symptom severity and medication use and improving of quality of life, with a long-lasting effect after the end of the course. The recent clinical trials evidenced AIT effectiveness and safety in allergic asthma. Consequently, the current version of the GINA (Global Initiative for Asthma) guidelines recommend AIT as an add-on therapy for asthma. There is also evidence that AIT may exert preventive activity on the possible progression from allergic rhinitis to asthma in children and the onset of new sensitizations. The present review provides a pragmatic summary of the clinical indications of AIT in pediatric asthma, including the immunological mechanisms, the predictive biomarkers, and the safety issues in clinical practice.