Food-specific IgG4-guided diet elimination improves allergy symptoms in children.

Allergic diseases in children are major public health concerns due to their widespread and rising prevalence. Food-specific immunoglobulin G4(FS-IgG4) has been detected in patients with allergic diseases, but its clinical significance is still debated. In the present study, 407 children with allergic diseases were recruited and categorized into three groups according to the different systems involved: the respiratory system group, the skin system group, and a multiple system group, with the collection of clinical symptoms and serum antibodies, including total immunoglobulin E (IgE), house dust mite (HDM) IgE, food-specific IgE (FS-IgE), and FS-IgG4. Part of these patients were followed up with the intervention of FS-IgG4-guided diet elimination with or without add-on probiotics supplement. The analysis at baseline revealed distinct serum levels of different antibodies. The positive rate of FS-IgG4 in all groups was more than 80%, and the proportion of total IgE and FS-IgG4 both positive in the multi-system group was the highest (p=0.039). Egg and milk were the foods with the highest positive rate of FS-IgG4 in all groups. After diet elimination for more than 3 months, serum FS-IgG4 in children significantly decreased (P<0.05) along with the improvement of clinical symptoms, regardless of the add-on of probiotics. However, the intervention did not impact the serum levels of total IgE, FS-IgE, and HDM IgE. There was no further decrease of serum FS-IgG4 level in children followed up for more than 1 year, which may be related to noncompliance with diet elimination. Multivariate regression analysis revealed that the decline of serum FS-IgG4 was an independent predictable factor for the improvement of clinical symptoms (adjusted OR:1.412,95%CI 1.017-1.96, p=0.039). The add-on of probiotics showed less efficiency in reducing the FS-IgG4 level in more patients with relief of clinical symptoms. Our results confirmed the correlation between FS-IgG4 and allergic diseases, and the decreased FS-IgG4 could be a useful predictor for the improvement of allergic symptoms. FS-IgG4-guided diet elimination is an efficient treatment for allergic diseases. Our study adds solid data to the clinical significance of FS-IgG4 in allergic diseases.

Successful treatment of dupilumab in Kimura disease independent of IgE: A case report with literature review.

Kimura disease (KD) is a rare and benign chronic inflammatory disease of unknown cause. It is characterized by subcutaneous granuloma of soft tissues in the head and neck region, increased eosinophil count, and elevated serum IgE. Currently, no definitive treatments are recommended. A 57-year-old Chinese man was diagnosed with KD after 7 years of slow subcutaneous masses growth. The patient underwent treatment of oral glucocorticoids for 1 year, but the masses recurred as the dosage was tapered down. Subsequent anti-IgE therapy of omalizumab administered subcutaneously at 450 mg/day at a 4-week interval did not show improvement. The size of masses and serum IgE and circulating eosinophils did not decrease significantly after 19 cycles of continuous treatment. Ultimately, switched strategy of dupilumab was applied at an initial dose of 600 mg, followed by 300 mg every 2 weeks for 4 months. This treatment demonstrated dramatical effects with reduced masses in each area and fast dropdown of eosinophil counts, while the high level of serum IgE remained without changes. Recently, different biologics including anti-IgE, anti-IL-5, and anti-IL-4/IL-13 have been applied to treat KD with satisfied results and help to explore the pathogenesis of this rare disease. To our knowledge, this is the first report that demonstrates the effects of two different biologics in the same patient and reveals the impressive clinical efficacy of dupilumab to treat KD independent of IgE. Therefore, further investigation of the underlying mechanism and the development of diagnosis and treatment of KD is valuable.

Evaluation of the Role of IgE Responses to Der p 1 and Der p 2 in Chinese House Dust Mite-Allergic Patients.

BACKGROUND: The role of specific IgE (sIgE) against Der p 1 and Der p 2 in Chinese patients with house dust mite (HDM) allergy has not yet been well investigated. METHODS: One hundred patients were enrolled, based on sensitization and doctor-diagnosed allergy to HDM. Questionnaires were administered to document demographic and clinical characteristics. Serum IgE reactivity to Dermatophagoides pteronyssinus (Dp) extract, Der p 1, Der p 2 and Der p 10 was measured by ImmunoCAP. RESULTS: Almost all patients were sensitized to Der p 1 (95%) and Der p 2 (93%), with both allergens together being largely responsible for the total anti-HDM IgE response. No evidence for a significant role of Der p 10 was found. Overall, IgE responses to HDM and its 2 major allergens were higher in children than in adults in this cross-sectional study. With increasing age, IgE responses to Der p 2 become more important. A positive correlation was observed between the reaction of sIgE against Dp, Der p 1 and Der p 2 and the number of organs (including the eyes, nose, lungs and skin) that were affected in patients. CONCLUSIONS: In China, Der p 1 and Der p 2 are the dominant allergens in patients with HDM allergy. The relative importance of Der p 1 and Der p 2 changes with age, in favor of Der p 2. Overall, sIgE titers were positively associated with the number of organs affected.

Sleep-related hypoxemia aggravates systematic inflammation in emphysematous rats.

BACKGROUND: Sleep disturbance is common in patients with emphysema. This study aimed to develop a novel model of sleep-related hypoxemia (SRH) in emphysema (SRHIE) with rats, and to explore the inflammatory status of SRHIE in lung, liver, pancreas, carotid artery and whole blood. METHODS: Seventy-five male Wistar rats were assigned to 5 groups with 15 per group according to the exposure conditions. The protocols varied with the degree of hypoxia exposure and severity of pre-existing emphysema caused by cigarette smoke exposure: (1) SRH control (SRHCtrl) group, sham smoke exposure (smoke exposure, exposed to smoke of 15 cigarettes twice everyday, 16 weeks) and SRH exposure (12.5% O2, 3 hours, SRH exposure, divide total hypoxia time (1.5 hours or 3 hours) into 4 periods evenly (22.5 minutes or 45 minutes) and distribute these hypoxia periods evenly into physiological sleep time of rats identified by electroencephalogram, week 9 to week 16); (2) Emphysema control (ECtrl) group, smoke exposure and sham SRH exposure (21% O2, 3 hours); (3) Short SRH in emphysema (SRHShort) group, smoke exposure and short SRH exposure (12.5% O2, 1.5 hours); (4) Mild SRH in emphysema (SRHMild) group, smoke exposure and mild SRH exposure (15% O2, 3 hours); (5) Standard SRH in emphysema (SRHStand) group, smoke exposure and SRH exposure (12.5% O2, 3 hours). ECtrl, SRHShort, SRHMild and SRHStand groups were groups with emphysematous rats. Two days before the end of exposure, 5 rats in each group were randomly selected for arterial blood gas analysis. In the rest 10 rats in each group, we obtained blood samples and bronchoalveolar lavage fluid (BALF) for routine tests. We also obtained tissue blocks of lung, liver, pancreas, and right carotid artery for pathologic scoring and measurements of liver oxidative stress (measuring hepatic oxidative stress enzymes, superoxide dismutase (SOD) activity, catalase (CAT) activity and malondialdehyde (MDA) concentration). RESULTS: Emphysematous groups had higher mean linear intercept (MLI) and mean alveolar number (MAN) values than SRHCtrl group. MLI values in SRHStand group were the highest (all P < 0.05). O2Sat in SRHStand rats when SRH exposure was (83.45 ± 1.76)%. Histological scores of lung, liver, pancreas and right carotid artery were higher in emphysematous groups than SRHCtrl group, and SRHStand group were the highest (all P < 0.05) (SOD and CAT values were lower and MDA values were higher in groups with emphysema than without and in SRHStand group than in ECtrl group (all P < 0.05)). MDA values were the highest in SRHStand group (all P < 0.05). Total cellular score in BALF and White blood cell (WBC) in whole blood were the highest in SRHStand group (all P < 0.05). Lymphocyte ratios were the highest in SRHStand group both in BALF and blood (all P < 0.05). Red blood cell (RBC) and hemoglobin in emphysematous groups were higher than that in SRHCtrl group, and SRHStand group were higher than ECtrl group (all P < 0.05). CONCLUSIONS: With a proper novo model of SRHIE with Wistar rats, we have demonstrated SRH may aggravate the degree of emphysematous changes, polycythemia, oxidative stress and systematic inflammation. SRH and emphysema may have a synergistic action in causing systematic damages, and lymphocyte may be playing a central role in this process. Longer duration and more severe extent of SRHIE exposure also seem to result in more serious systematic damages. The mechanisms of all these concerned processes remain to be studied.