Profilin sensitisation in a Mediterranean population

Recombinant Art v4.01 protein produces immunological tolerance by subcutaneous immunotherapy in a wormwood pollen-driven allergic asthma female mouse model

Art v4.01 is a well-known profilin protein belonging to the pan-allergens group and is commonly involved in triggering allergic asthma, polyallergy, and cross-sensitization. It is also referred to as Wormwood due to its origin. Crude wormwood extracts are applied for allergen-specific immunotherapy (AIT). Whether the recombinant Art v4.01 (rArt v4.01) can produce in vivo immunological tolerance by subcutaneous immunotherapy (SCIT) remains elusive. In this study, to investigate the in vivo immunological response of rArt v4.01, Th2, Th1, Treg, Th17 type-related cytokines and phenotypes of immune cells were tested, facilitating the exploration of the underlying mechanisms. The expression and purification of Art v4.01 were carried out using recombinant techniques. Allergic asthma female BALB/c mice were induced by subcutaneous sensitization of wormwood pollen extract and intranasal challenges. SCIT without adjuvant was performed using the rArt v4.01 and wormwood pollen extract for 2 weeks. Following exposure to challenges, the levels of immunoglobulin E (IgE), cytokines, and inflammatory cells were assessed through enzyme-linked immunosorbent assay (ELISA) and histological examination of sera, bronchoalveolar lavage fluid (BALF), and lung tissue. These parameters were subsequently compared between treatment groups receiving rArt v4.01 and wormwood pollen extract. The rArt v4.01 protein was expressed, which had a high purity (>90%) and an allergenic potency. Compared with the pollen extract, rArt v4.01 was superior in terms of reducing the number of white blood cells (WBCs), total nucleated cells (TNCs), and monocytes (MNs) in BALF and the degree of lung inflammation (1.77±0.99 vs. 2.31±0.80, P > 0.05). Compared with the model group, only rArt v4.01 reduced serum IgE level (1.19±0.25 vs. 1.61±0.17 μg/ml, P = 0.062), as well as the levels of Th2 type-related cytokines (interleukin-4 (IL-4) (107.18±16.17 vs. 132.47±20.85 pg/ml, P < 0.05) and IL-2 (19.52±1.19 vs. 24.02±2.14 pg/ml, P < 0.05)). The study suggested that rArt v4.01 was superior to pollen extract in reducing the number of inflammatory cells in BALF, pneumonitis, levels of pro-inflammatory cytokines, and serum IgE level. These findings confirmed that Art v4.01 could be a potential candidate protein for allergen-specific immunotherapy.

Immunoproteomic identification of allergenic proteins in pecan (Carya illinoinensis) pollen

Pecan (C. illinoinensis) pollen is an important cause of allergic respiratory disease. Pecan is distributed worldwide as shade, ornamental or cultivation tree. To date three well known pecan food allergens have been reported, however, pollen allergens have not been identified. Here, we describe the first identification of IgE recognized pecan pollen proteins, for which proteins were analyzed by 2-DE and immunoblotting using a pool of 8 sera from pecan sensitive patients as primary antibody. IgE recognized protein spots were analyzed by LC-MS/MS and identified using a database of translated protein sequences obtained by the assembly of C. illinoinensis public transcriptomic information. This study has identified 17 IgE binding proteins from pecan pollen including proteins widely recognized as allergens and panallergens. These findings will contribute to develop specific diagnosis and treatment of pecan pollen allergy. SIGNIFICANCE: Pecan is a tree highly valued for its fruits that have a great commercial value. To date three pecan seed storage proteins have been officially recognized by the WHO/IUIS allergen nomenclature subcommittee as food allergens (Car i 1, Car i 2 and Car i 4). Pecan tree pollen is highly allergenic and a clinically relevant cause of allergies in North America (USA and Mexico) and regions where the tree is extensively cultivated (Israel, South Africa, Australia, Egypt, Peru, Argentina, and Brazil). Here, we describe the first identification of IgE recognized pollen proteins using an immunoproteomics approach and a protein database created by the assembly of pecan public transcriptomic information. The findings described here will allow the development of new diagnostic and therapeutic modalities for pecan pollen allergy.

Study of the Expected Impact of Palm Pollen on Human Respiratory Tract Allergy

&lt;b&gt;Background and Objective:&lt;/b&gt; Date-Palm trees (&lt;i&gt;Phoenix dactylifera&lt;/i&gt; L.) are the most abundant crop in Saudi Arabia. Date Palm Pollen (DPP) are considered an important allergens. The reasons for the increase in susceptibility to allergy are not clear. This investigation aimed to link the size, shape, moisture contents and biogenic contents of the collected pollens to susceptibility. &lt;b&gt;Materials and Methods:&lt;/b&gt; Pollens were collected from three different regions in the Kingdom. Date palm pollen sizes were determined in wet and dry states by Microtrac. A microscope with a camera was used to image the forms of date palm pollens. The biogenic amines were determined after extraction using HPLC. Data were analyzed by one-way analysis of variance (ANOVA), using SPSS version 16.0. &lt;b&gt;Results:&lt;/b&gt; There was a variation in the sizes of pollens from different regions ranging between 3.3-704 μm. Most pollen grains are spherical. The concentrations of six biogenic amines were detected in all samples but with different concentrations. They included B-phenyl ethylamine, Putrescine, Cadaverine, Histamine, Tyramine and Spermidine. &lt;b&gt;Conclusion:&lt;/b&gt; The shape and size of the pollen grains studied were variable and will not facilitate deep penetration into the respiratory system but their biogenic contents were very high and suggested to cause allergy.

The Role of Enolases in Allergic Disease

Enolase is one of the most abundant cytosolic enzymes as well as an important glycolytic metalloenzyme highly conserved among organisms from different taxonomical groups. Participation of enolase in processes in which its enzymatic activity is not required has been widely reported. Some of these processes provide special qualities to microorganisms, which favor, in some cases, their pathogenicity. Remarkably, enolase has been reported as an allergen by itself, it is well recognized as allergenic in molds and yeasts, whereas it has also been recognized by the immune system of susceptible individuals acting as a food and inhaled allergen from other diverse sources such as insects, birds, fishes, and plants. To date, 14 enolases have been officially recognized by the World Health Organization/International Union of Immunological Societies Allergen Nomenclature Subcommittee. The use of discovery proteomics has also uncovered novel allergenic enolases, particularly from pollen sources. Here, we review the relevance of enolases as sensitizers and as nonsensitizing cross-reactive allergens in allergic disease.

A robust method for the estimation and visualization of IgE cross-reactivity likelihood between allergens belonging to the same protein family

Among the vast number of identified protein families, allergens emanate from relatively few families which translates to only a small fraction of identified protein families. In allergy diagnostics and immunotherapy, interactions between immunoglobulin E and allergens are crucial because the formation of an allergen-antibody complex is necessary for triggering an allergic reaction. In allergic diseases, there is a phenomenon known as cross-reactivity. Cross-reactivity describes a situation where an individual has produced antibodies against a particular allergenic protein, but said antibodies fail to discriminate between the original sensitizer and other similar proteins that usually belong to the same family. To expound the concept of cross-reactivity, this study examines ten protein families that include allergens selected specifically for the analysis of cross-reactivity. The selected allergen families had at least 13 representative proteins, overall folds that differ significantly between families, and include relevant allergens with various potencies. The selected allergens were analyzed using information on sequence similarities and identities between members of the families as well as reports on clinically relevant cross-reactivities. Based on our analysis, we propose to introduce a new A-RISC index (Allergens’–Relative Identity, Similarity and Cross-reactivity) which describes homology between two allergens belonging to the same protein family and is used to predict the likelihood of cross-reactivity between them. Information on sequence similarities and identities, as well as on the values of the proposed A-RISC index is used to introduce four categories describing a risk of a cross-reactive reaction, namely: high, medium-high, medium-low and low. The proposed approach can facilitate analysis in component-resolved allergy diagnostics, generation of avoidance guidelines for allergic individuals, and help with the design of immunotherapy.

Prevalence of Skin Sensitization to Pollen of Date Palm in Marrakesh, Morocco

Background. Date palm's pollen has been identified as a source of allergy; the rate of sensitization of this pollen is between 6 and 29%. Objective. To determine the prevalence of sensitization to date palm in Marrakesh and to identify the clinical profile. Patients and Methods. This study is based on a questionnaire and the prick test on 7 allergens, in population aged 5 years and above with clinical symptoms suggesting allergic diseases, from November 2012 to February 2013 in Marrakech. Results. We included 468 patients (women: 79.5%). The prick tests were considered interpretable in 467 cases. The prevalence of skin sensitization to pollen of date palm was 6.6%. The 31 cases of sensitization to date palm involved 7 men and 24 women with an average age of 37.5 years. Cutaneous monosensitization to date palm's pollen was observed in 2 cases. Asthma, rhinitis, and conjunctivitis were recorded, respectively, in 48.4%, 93.5%, and 67.7%. Conclusion. Skin sensitization to pollen of date palm does not seem unusual among allergic patients in Marrakech and is comparable to that found in Casablanca (7%), Barcelona (6.6%), and Cartagena (6.1%).

How relevant is panallergen sensitization in the development of allergies?

Panallergens comprise various protein families of plant as well as animal origin and are responsible for wide IgE cross-reactivity between related and unrelated allergenic sources. Such cross-reactivities include reactions between various pollen sources, pollen and plant-derived foods as well as invertebrate-derived inhalants and foodstuff. Here, we provide an overview on the most clinically relevant panallergens from plants (profilins, polcalcins, non-specific lipid transfer proteins, pathogenesis-related protein family 10 members) and on the prominent animal-derived panallergen family, tropomyosins. In addition, we explore the role of panallergens in the sensitization process and progress of the allergic disease. Emphasis is given on epidemiological aspects of panallergen sensitization and clinical manifestations. Finally, the issues related to diagnosis and therapy of patients sensitized to panallergens are outlined, and the use of panallergens as predictors for cross-reactive allergy and as biomarkers for disease severity is discussed.

Profilin desensitization: A case series

The role of profilin as an allergen has long been questioned. The capacity of profilin to induce respiratory symptoms has recently been demonstrated; moreover, over 50% of patients sensitized to profilin experienced symptoms after the ingestion of plant-derived foods, suggesting that profilin should be considered as a clinically relevant food allergen.We describe the cases of seven allergic patients with oral allergy syndrome and other adverse reactions after eating plant-derived food, that have been undergone to profilin desensitization treatment.The protocol started with a drop of profilin solution (50 µg/mL) diluted 1:10(18) in water until the highest dose of 10 drops of undiluted solution three times a week. At the end of the treatment we observed a decreased mean diameter of profilin wheal in skin prick test (SPT) in five of the seven participants and in profilin specific IgE values in six patients that repeated the test. Regarding basophil activation test (BAT) and the detection of IgG4, we do not have significant results because the tests have to be repeated in some patients. Regarding the double-blind placebo-controlled challenges, after about 10 months of induction phase all the patients showed tolerance to several foods that they previously did not tolerate.Moreover, the immunotherapy with profilin has proved to be safe because no serious adverse events have been reported in our patients.In summary, the results of this exploratory study of sublingual immunotherapy (SLIT) for profilin allergy show that it can be a promising therapeutic option that could modify the clinical reactivity of the patients to the intake of plant-derived food.

Adverse reactions to immunotherapy are associated with different patterns of sensitization to grass allergens

The aim of the study was to investigate whether adverse drug reactions (ADRs) during immunotherapy with a grass extract (AVANZ® Phleum, ALK-Abelló) are related to the different patterns of sensitization of patients to grass allergens. A total of 192 patients with rhinitis and/or asthma sensitized to grass pollen received a 4-week updosing with five injections. ADRs were evaluated following EAACI guidelines. A total of 432 ADRs in 133 (69%) patients were recorded, 64% local and 31% systemic. There was a significant association between the number of grass allergens that sensitized the patients and the total number of ADRs (P = 0.004) occurred locally (P = 0.003) and systemically (P = 0.01). Sensitization to Phl p1 + Phl p5 or Phl p1 + Phl p5 + Phl p12 was significantly associated with a higher frequency of local or systemic reactions (P = 0.001, both). Different patterns of sensitization to grass allergens may potentially be considered a risk marker to the development of ADRs to immunotherapy.