The impact of type 2 immunity and allergic diseases in atherosclerosis.

Allergic diseases are allergen-induced immunological disorders characterized by the development of type 2 immunity and IgE responses. The prevalence of allergic diseases has been on the rise alike cardiovascular disease (CVD), which affects arteries of different organs such as the heart, the kidney and the brain. The underlying cause of CVD is often atherosclerosis, a disease distinguished by endothelial dysfunction, fibrofatty material accumulation in the intima of the artery wall, smooth muscle cell proliferation, and Th1 inflammation. The opposed T-cell identity of allergy and atherosclerosis implies an atheroprotective role for Th2 cells by counteracting Th1 responses. Yet, the clinical association between allergic disease and CVD argues against it. Within, we review different phases of allergic pathology, basic immunological mechanisms of atherosclerosis and the clinical association between allergic diseases (particularly asthma, atopic dermatitis, allergic rhinitis and food allergy) and CVD. Then, we discuss putative atherogenic mechanisms of type 2 immunity and allergic inflammation including acute allergic reactions (IgE, IgG1, mast cells, macrophages and allergic mediators such as vasoactive components, growth factors and those derived from the complement, contact and coagulation systems) and late phase inflammation (Th2 cells, eosinophils, type 2 innate-like lymphoid cells, alarmins, IL-4, IL-5, IL-9, IL-13 and IL-17).

Profilin-mediated food-induced allergic reactions are associated with oral epithelial remodeling.

BACKGROUND: In areas of high exposure to grass pollen, allergic patients are frequently sensitized to profilin, and some experience severe profilin-mediated food-induced reactions. This specific population of patients is ideal to study the relationship between respiratory and food allergies. OBJECTIVE: We sought to determine the role of oral mucosal epithelial barrier integrity in profilin-mediated allergic reactions. METHODS: Thirty-eight patients with profilin allergy stratified into mild or severe according to their clinical history and response to a profilin challenge test and 6 nonallergic subjects were recruited. Oral mucosal biopsies were used for measurement of CD11c, CD3, CD4, tryptase, claudin-1, occludin, E-cadherin, and vascular endothelial growth factor A levels; Masson trichrome staining; and POSTN, IL33, TPSAB, TPSB, and CMA gene expression analysis by using quantitative RT-PCR. Blood samples were used for basophil activation tests. RESULTS: Distinct features of the group with severe allergy included the following: (1) impaired epithelial integrity with reduced expression of claudin-1, occludin, and E-cadherin and decreased numbers of epithelial cells, which is indicative of acanthosis, higher collagen deposition, and angiogenesis; (2) inflammatory immune response in the mucosa, with an increased number of CD11c+ and CD4+ infiltrates and increased expression of the cytokine genes POSTN and IL33; and (3) a 10-fold increased sensitivity of basophils to profilin. CONCLUSIONS: Patients with profilin allergy present with significant damage to the oral mucosal epithelial barrier, which might allow profilin penetration into the oral mucosa and induction of local inflammation. Additionally, severely allergic patients presented with increased sensitivity of effector cells.

Egg OIT in clinical practice (SEICAP II): Maintenance patterns and desensitization state after normalizing the diet.

BACKGROUND: It is unknown which are the most suitable maintenance pattern and egg consumption to maintain the desensitization state after ending the oral immunotherapy (OIT). This multicenter, randomized, controlled trial compared two OIT maintenance patterns with pasteurized egg white (PEW), evaluating the egg consumption effect on the desensitization state after ending the OIT. METHODS: One hundred and one children with confirmed egg allergy were randomized: 25 to an egg-free diet (CG) and 76 to an OIT year with PEW and two maintenance patterns, 38 patients to daily 3.3 g proteins (AG) and 38 to every two days (BG). PEW challenge (DBPCFC), adverse reactions, and immune markers were assessed at baseline, at the end of the OIT, and at 6 and 12 months later on ad libitum egg consumption (T0, T12, T18, and T24). A questionnaire evaluated the egg consumption at T18. RESULTS: At T12, 64 of 76 (84.21%) OIT patients had reached total desensitization (32 AG and 32 BG) vs 4 of 25 (16.00%) CG who passed the PEW DBPCFC. Thirty (93.75%) AG vs 25 (78.12%) BG patients completed an OIT year. At T18, 27 of 29 (93.1%) AG vs 20 of 24 (83.3%) BG passed the PEW DBPCFC, 96% consuming at least two egg servings/week. At T24, 97.43% OIT patients passed the challenge. Most patients had adverse reactions, more frequent in the BG patients; frequency and severity of reactions decreased through the study. PEW skin prick test wheal and sIgE antibody serum levels similarly decreased in AG or BG, but AG patients had greater increase in PEW sIgG4 (P < 0.05). CONCLUSIONS: Daily OIT maintenance achieves better adherence, effectiveness, and safety. Two egg servings/week ensure maintained desensitization after the end of an OIT year.

Egg oral immunotherapy in children (SEICAP I): Daily or weekly desensitization pattern.

BACKGROUND: Studies are required before incorporating egg oral immunotherapy (OIT) into clinical practice. The Spanish Society of Pediatric Allergy, Asthma and Clinical Immunology (SEICAP) conducted a multicenter, randomized controlled study assessing the effectiveness and safety of the OIT using pasteurized egg white (PEW) in egg-allergic children. METHODS: One hundred and one egg-allergic children (6-9 years) were randomized for 1 year: 25 to an egg-free-diet (CG) and 76 to OIT (target dose 3.3 g PEW proteins), PI (30% weekly plus 5% daily increments) or PII (only 30% weekly increments) buildup patterns. Egg skin prick test, sIgE and sIgG4 serum levels, PEW double-blind placebo-controlled food challenge (DBPCFC), and dosing adverse reactions (DARs) were evaluated in all patients from inclusion (T0) until completing 1 year of follow-up (T12). At T12, egg-allergic control patients could start OIT. The effectiveness and safety of OIT and the effect of the buildup pattern were analyzed. RESULTS: At T12, 4/25 (16.0%) CG patients passed the PEW DBPCFC vs 64/76 (84.2%) OIT that reached total desensitization (P = 0.000); 12 egg-allergic control patients started OIT. Finally, 72/88 (81.81%) patients reached total desensitization, 96.15% PI vs 75.80% on PII (P = 0.01). Induction period (121.12 ± 91.43, median 98.00 days) was longer in patients on PII buildup pattern, and those with allergic asthma, minor threshold dose, or higher egg sIgE (P < 0.05). Most patients (89.06%) developed DARs: 74.53% were mild; 21.90% moderate; and 3.5% requiring adrenaline-treatment. Moderate reactions and those requiring adrenaline were more frequent in patients with allergic asthma, PII pattern, or higher egg sIgE serum antibody levels (P < 0.05). CONCLUSIONS: PEW OIT is an effective treatment for children with persistent egg allergy. A 30% weekly plus 5% daily increment pattern could be more effective and safer than one with only 30% weekly increments.

Efficacy and safety of oral desensitization in children with cow's milk allergy according to their serum specific IgE level.

BACKGROUND: Oral desensitization in children allergic to cow's milk proteins is not risk free. The analysis of factors that may influence the outcome is of utmost importance. OBJECTIVE: To analyze the efficacy and safety of the oral desensitization according to specific IgE (sIgE) level and adverse events during the maintenance phase. METHODS: Thirty-six patients allergic to cow's milk (mean age, 7 years) were included in an oral desensitization protocol. Patients were grouped according to sIgE levels (ImmunoCAP) into groups 1 (sIgE <3.5 kU/L), 2 (3.5-17 kU/L), and 3 (>17-50 kU/L). Nineteen children were included as a control group. Serum sIgE levels to cow's milk and its proteins were determined at inclusion and 6 and 12 months after finishing the desensitization protocol. RESULTS: Thirty-three of 36 patients were successfully desensitized (200 mL): 100% of group 1 and 88% of groups 2 and 3. Desensitization was achieved in a median of 3 months (range, 1-12 months); 90% of the patients in group 1, 50% of the patients in group 2, and 30% of the patients in group 3 achieved tolerance in less than 3 months (P = .04). In the control group only 1 child tolerated milk in oral food challenge after 1 year. During the induction phase, there were 53 adverse events in 27 patients (75%). Patients of groups 2 and 3 had more severe adverse events compared with group 1. During the maintenance phase, 20 of 33 patients (60%) had an adverse event. CONCLUSION: Oral desensitization is efficacious. Tolerance is achieved earlier when sIgE is lower. Severe adverse events are frequent, especially in patients with higher sIgE levels.