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In vivo animal models can provide worthy information on various aspects of asthma mechanism and pathogenesis. The genetic predisposition and phenotype of mice may affect the immune response itself. Here we compare the early immune response to Der p 2 or HDM allergen extract upon injection and inhalation in BALB/c and C57BL/6 mice. Female C57BL/6 and BALB/c mice were immunized with Der p 2 allergen subcutaneously followed by inhalation of Der p 2 or HDM extract. After challenge, the mice were euthanized; blood, bronchoalveolar lavage (BAL), spleens and lungs were collected. Cells from BAL were identified by May-Grünwald Giemsa staining and lung leukocyte populations were analyzed by flow cytometry. Serum antibody levels of Der p 2 specific IgE, IgG, IgG1 and IgG2a were assessed by ELISA, and cytokine secretion (IL-4, IFN-γ and IL-10) was evaluated upon stimulation with Der p 2 or HDM extract. The Th2 immune response was confirmed by elevated allergen-specific immunoglobulin E (IgE) and the allergic reaction was evidenced by infiltration of eosinophils and/or neutrophils into BAL. We found that BALB/c mice were inefficient in integrating local with systemic immune response, evidenced by almost no IgG or IgE production upon one subcutaneous injection and subsequent inhalation of Der p 2 allergen; also, the bronchoalveolar lavage infiltrate in these mice consisted of neutrophil infiltration, unlike C57BL/6 mice in which eosinophilic infiltrate predominated. The differences between BALB/c and C57BL/6 mice strains could be exploited for generating different types of responses to the Der p 2 allergen.

The aim of this study was to identify short digestion-resistant peptides (SDRPs) released by pepsin digestion of the whole cow’s milk and examine their IgE reactivity and allergenicity. Raw milk was subjected to simulated gastric digestion. SDRPs were fractionated from the digests and identified by MS. Milk SDRPs were evaluated for aggregability, propensity to compete for IgE binding with individual milk allergens, and ability to bind IgG4 from allergic and milk-tolerant individuals. The majority of milk SDRPs originated from caseins (97% of peptides) and overlapped with the known IgE epitopes of cow’s milk allergens. SDRPs competed with milk proteins for binding to human IgE and readily formed aggregates. The average peptide length was 10.6 ± 3.5 amino acids. The ability to provoke allergenic in vivo responses was confirmed by skin-prick testing (SPT) in five milk-allergic subjects. This was attributed to the peptide ability to aggregate into non-covalent complexes. SDRPs are able to induce response in SPT, but only in 50% of the sera SDRPs were able to inhibit IgG4 binding to caseins. Hence, SDRPs corresponding to the mainly continuous epitopes of milk proteins induce allergenic in vivo responses in milk-allergic subjects due to aggregation.

Background and objectives: The relationship between air pollen quantity and the sensitization of allergic patients is crucial for both the diagnosis and treatment of allergic diseases. Weather conditions influence the distribution of allergenic pollen and increases in pollen concentration may negatively affect the health of allergic patients. The aim of this study was to analyze the implementation of allergen immunotherapy with regard to air pollen concentration. Material and Methods: Here we examined the relationship between Betula air pollen concentration and the usage of Betula verrucosa allergen immunotherapy in Serbia. Examination covered the period from 2015 to 2018. Measurement of airborne pollen concentration was performed with Lanzoni volumetric pollen traps. The evidence of the usage of sublingual allergen immunotherapy (SLIT) was gathered from patients with documented sensitization to specific pollen. Results: During this period tree pollens were represented with 58% &plusmn, 21% of all measured air pollen species, while Betula pollen represented 15% &plusmn, 8% of all tree pollens. Betula pollination peaked in April. Allergen immunotherapy to Betula verrucosa in Serbia is entirely conducted as sublingual immunotherapy and represents 47.1% &plusmn, 1.4% of issued tree pollen SLIT. The use of pollen SLIT increased by 68% from 2015 to 2018, with an even greater increase in usage recorded for Betula SLIT&mdash, 80%. Conclusions: This analysis shows a clear causative relationship between pollination and the type/prevalence of applied allergen immunotherapy. Information about the flowering seasons of allergenic plants is very important for people who suffer from allergy, for clinical allergologists, as well as for governing authorities. The presented data is of practical importance to the proper timing of immunotherapy initiation and of importance for urban landscaping. The obtained data can be the starting point for the instatement of a thorough epidemiological study and the inclusion of Serbia on the pollen map of Europe.

BackgroundMost food allergens sensitizing via the gastrointestinal tract are stable proteins that are resistant to pepsin digestion, in particular major peanut allergens, Ara h 2 and Ara h 6. Survival of their large fragments is essential for sensitizing capacity. However, the immunoreactive proteins/peptides to which the immune system of the gastrointestinal tract is exposed during digestion of peanut proteins are unknown. Particularly, the IgE reactivity of short digestion-resistant peptides (SDRPs; lt 10kDa) released by gastric digestion under standardized and physiologically relevant invitro conditions has not been investigated. ObjectiveThe aim of this study was to investigate and identify digestion products of major peanut allergens and in particular to examine IgE reactivity of SDRPs released by pepsin digestion of whole peanut grains. MethodsTwo-dimensional gel-based proteomics and shotgun peptidomics, immunoblotting with allergen-specific antibodies from peanut-sensitized patients, enzyme-linked immunosorbent inhibition assay and ImmunoCAP tests, including far ultraviolet-circular dichroism spectroscopy were used to identify and characterize peanut digesta. ResultsAra h 2 and Ara h 6 remained mostly intact, and SDRPs from Ara h 2 were more potent in inhibiting IgE binding than Ara h 1 and Ara 3. Ara h 1 and Ara h 3 exhibited sequential digestion into a series of digestion-resistant peptides with preserved allergenic capacity. A high number of identified SDRPs from Ara h 1, Ara h 2 and Ara h 3 were part of short continuous epitope sequences and possessed substantial allergenic potential. Conclusion and Clinical RelevancePeanut grain digestion by oral and gastric phase enzymes generates mixture of products, where the major peanut allergens remain intact and their digested peptides have preserved allergenic capacity highlighting their important roles in allergic reactions to peanut. This is the peer-reviewed version of the article: Prodić, I.; Stanić-Vučinić, D.; Apostolović, D.; Mihailović-Vesić, J.; Radibratović, M.; Radosavljević, J.; Burazer, L. M.; Milčić, M. K.; Smiljanić, K.; van Hage, M.; Ćirković-Veličković, T. Influence of Peanut Matrix on Stability of Allergens in Gastric-Simulated Digesta: 2S Albumins Are Main Contributors to the IgE Reactivity of Short Digestion-Resistant Peptides. Clinical and Experimental Allergy 2018, 48 (6), 731–740. [https://doi.org/10.1111/cea.13113]. Supplementary material: [https://cherry.chem.bg.ac.rs/handle/123456789/3225]

Phenolic composition of Ambrosia artemisiifolia L. pollen and sub-pollen particles (SPP) aqueous extracts was determined, using a novel extraction procedure. Total phenolic and flavonoid content was determined, as well as the antioxidative properties of the extract. Main components of water-soluble pollen phenolics are monoglycosides and malonyl-mono- and diglycosides of isorhamnetin, quercetin and kaempferol, while spermidine derivatives were identified as the dominant polyamides. SPP are similar in composition to pollen phenolics (predominant isorhamnetin and quercetin monoglycosides), but lacking small phenolic molecules ( lt 450 Da). Ethanol-based extraction protocol revealed one-third lower amount of total phenolics in SPP than in pollen. For the first time in any pollen species, SPP and pollen phenolic compositions were compared in detail, with an UHPLC/ESI-LTQ-Orbitrap-MS-MS approach, revealing the presence of spermidine derivatives in both SPP and pollen, not previously reported in Ambrosia species. (C) 2014 Elsevier Ltd. All rights reserved.

Actinidin, a cysteine protease accounting for more than 50% of the soluble proteins in kiwifruit pulp, has shown promise as a milk-clotting agent. In this study, the potential use of kiwifruit pulp extract as a clotting agent was investigated. It was shown that three kiwifruit extracts made from the pulp of a single fruit have significantly different levels of active actinidin, depending on the extraction buffer employed. Kiwifruit extract prepared at pH 5.0 had the best milk-clotting properties, with a nearly 30% better ratio of clotting activity to proteolytic activity than purified actinidin. This extract produced a casein coagulum clearly separated from the whey proteins, and was shown to be stable at room temperature for up to two months. This extract has the potential to be employed as an efficient and low-cost milk-clotting agent in the production of dairy products. Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3502]

Modified allergens are a safer and more efficient alternative to natural allergens for specific immunotherapy. As the modification of an allergen can diminish its immunogenicity due to the alteration of T-cell epitopes, in this paper we study the effects of a reversible chemical modification of Art v 1, the main allergen of mugwort pollen, on its allergenicity and immunogenicity. Modification of Art v 1 by cis-aconitylation into a polyanionic derivative (CAA) did not result in any significant structural alteration. However, IgE-binding epitopes on CAA were blocked, resulting in a reduced IgE-binding and basophil activation. Both proteins induced proliferation of CD3(+)CD4(+) T-cells in mugwort-allergic patients, but only unmodified allergens increased IL-4, IL-5 and IL-10 production. Rabbit and mouse anti-CAA antibodies exhibited cross-reactivity with native allergens and blocked human IgE-binding to Art v 1. Degradation of CAA by lysosomal fraction enzymes resulted in a similar set of peptides, harboring MHC class II-binding peptides, as unmodified proteins. Thus, cis-aconitylation modified Art v 1 had a significantly reduced allergenicity, whereas its immunogenicity was completely preserved. Acid-environment-responsive modification, which releases a full repertoire of native allergen epitopes within a particular site, can be considered a smart drug delivery system, which is able to deliver a therapeutically-effective dose in a controlled manner, and minimizes adverse side effects. Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3528]

For the heterologous production of a banana glucanase in Escherichia coli, its gene (GenBank GQ268963) was cloned into a pGEX-4T expression vector as a fusion protein with glutathione-S-transferase (GST). BL21 cells transformed with the GST-Mus a 5 construct were employed for the protein production induced by 1 mM of isopropyl-?-D-tiogalactopyranoside (IPTG). Conditions for the protein expression were optimized by varying the temperature (25?C, 30?C, and 37?C) and duration of protein expression (3h, 6h and 12h). The level of protein production was analyzed by densitometry of sodium dodecyl sulfate - polyacrylamide gel (SDS-PAG) after electrophoretic resolution of respective cell lysates. The optimal protein expression for downstream processing was obtained after 12h of cell growth under 25?C upon addition of IPTG. Recombinant GST-Mus a 5 purified by glutathione affinity chromatography revealed a molecular mass of about 60 kDa. The IgE and IgG reactivity of rGST-Mus a 5 was confirmed by dot blot analysis with individual patient?s sera from subjects with banana allergy and polyclonal rabbit antibodies against banana extract, respectively. Purified recombinant glucanase is a potential candidate for banana allergy diagnosis.

The thermal stability of recombinant mannose-specific banana lectin (rBanLec), as well as its stability under conditions of simulated gastro-intestinal fluid (SGF), was investigated. rBanLec was heterologously produced in Escherichia coli, Molecular mass of rBanLec, assessed by ESI-TOF mass spectrometry, was 15972.2 Da. Thermodynamic parameters for rBanLec denaturation, obtained by differential scanning calorimetry (DSC), revealed a transition maximum temperature (T(m)) of 60.8 degrees C, calorimetric enthalpy (H(cal)) of 136.17 kcal/mol and van't Hoff enthalpy (H(VH)) of 50.27 kcal/mol. rBanLec was stable following an incubation for 2 h in SGF, and then for I h, in the simulated intestinal fluid (SIF). Intact primary structure, biological and immunological reactivity of rBanLec were all preserved following treatment under SGF and SIF conditions. In conclusion, rBanLec is a good candidate for the novel bioadhesive lectin-based drug delivery systems to the gastro-intestinal tract (GIT). (C) 2009 Elsevier Ltd. All rights reserved.

Allergen-specific immunotherapy with house dust mite (HDM) allergen extracts can effectively alleviate the symptoms of allergic rhinitis and asthma. The efficacy of the immunotherapeutic treatment is highly dependent on the quality of house dust mite vaccines. This study was performed to assess the stability of house dust mite allergen vaccines prepared for sublingual immunotherapy. Lyophilized Dermatophagoides pteronyssinus (Dpt) mite bodies were the starting material for the production of sublingual vaccines in four therapeutic concentrations. The stability of the extract for vaccine production, which was stored below 4 degrees C for one month, showed consistence in the protein profile in SDS PAGE. ELISA-inhibition showed that the potencies of Dpt vaccines during a 12 month period were to 65-80 % preserved at all analyzed therapeutic concentrations. This study showed that glycerinated Dpt vaccines stored at 4 degrees C preserved their IgE-binding potential during a 12 month period, implying their suitability for sublingual immunotherapeutic treatment of HDM allergy. Alergen-specifična imunoterapija predstavlja postupak koji može da promeni tok bolesti kod alergijskog rinitisa i astme. Kvalitet vakcine pripremljene od kućnih grinja značajno utiče na efikasnost imunoterapeutskog tretmana. Ispitivanje je imalo za cilj procenu stabilnosti vakcine kućnih grinja namenjene za sublingvalnu imunoterapiju. Telo liofilozovanih Dermatophagoides pteronyssinus grinja (Dpt-grinja) upotrebljeno je kao polazni materijal za proizvodnju sublingvalne vakcine u 4 različita terapeutska razblaženja. Potentnost Dpt vakcina praćena ELISA-inhibicijom u 4 terapeutska razblaženja, nakon 12 meseci zadržan je u svim razblaženjima u opsegu 65-80%. Ispitivanje je pokazalo da glicerolom stabilizovane Dpt vakcine za subligvalnu imunoterapiju, uz čuvanje na 4°C zadržavaju alergeni potencijal ( gt 65%) nakon 12 meseci od njihove pripreme, i kao takve mogu se koristiti za tretman alergije na kućne grinje.

BACKGROUND: It is thought that food sensitisers must be able to reach the intestine in order to sensitise patients. Pectin is a gel-forming plant polysaccharide that can protect allergens from in vivo gastric digestion and in vitro pepsin digestion. The aim of this study was to examine if pectin gel formed in the acidic environment of the stomach can protect labile allergen from in vitro gastrointestinal digestion. RESULTS: Pectin forms a gel in the acidic conditions of gastric fluid up to a concentration of 1.0 ± 0.14 g L−1. Four allergenic fruits (kiwi, cherry, apple and banana) form gels in the same manner at the dilutions 14.8 ± 0.4; 8.4 ± 0.2, 9.4 ± 0.35 and 29.1 ± 0.2, respectively. The time necessary for dissolution of 50 g L−1 pectin gel in intestinal fluid was found to be 70 ± 0.2 min. Pectin gel formed in situ was able to protect Act c 1 from pepsin digestion for 1 h and from further intestinal digestion for one additional hour. CONCLUSION: Pectin gel in an acidic environment protects Act c 1 from pepsin digestion and dissolves slowly in the slightly basic environment of the intestine allowing the survival of fruit allergen for additional time and possible interaction with the gut immune system. Copyright © 2008 Society of Chemical Industry

Art v 1 is the major allergen of mugwort (Artemisia vulgaris) pollen, a significant cause of hay fever all over Europe. Specific immunotherapy is the only treatment modality for allergic disease. Application of modified allergens makes the treatment safer and more efficient. In this work, two out of three (citraconic anhydride, cis-aconitic anhydride, 2,3-dimethylmaleic anhydride) tested anhydrides were proven to be suitable for chemical modifications of allergens. Art v 1 was modified by cis-aconitylation and citraconylation in order to obtain derivatives of Art v 1 that may be suitable for further immunological testing. Acylation of Art v 1 gave derivatives (caaArt v 1 and citArt v 1) with about 80 % modified amino groups. The derivatives were in the monomeric form and had dramatically reduced pI values. Both derivatives were relatively stable at neutral pH values, while the acyl groups undergo hydrolysis under acidic conditions. Modification of allergens by cis-aconitylation and citraconylation could be a new tool for obtaining allergoids. Art v1 je glavni alergen polena crnog pelina (Artemisia vulgaris), značajnog uzročnika polenske groznice širom Evrope. Alergen-specifična imunoterapija je za sada jedini delotvoran način za tretiranje alergija, pri čemu primena modifikovanih alergena čini ovakav tretman bezbednijim i efikasnijim. U ovom radu, dva od tri (anhidrid cis-akonitne, citrakonske i 2,3-dimetilmaleinske kiseline) ispitivana anhidrida su se pokazala pogodnim za hemijske modifikacije alergena. Art v 1 je modifikovan cis-akonitilovanjem i citrakonilovanjem u cilju dobijanja derivata Art v 1 pogodnih za dalje imunološke testove. Acilovanjem Art v 1 dobijeni su derivati (caaArt v 1 i citArt v 1) sa oko 80 % izmodifikovanih amino grupa. Dobijeni derivati su monomerni, sa molekulskom masom sličnom nativnom Art v 1, ali sa dramatično smanjenim pI vrednostima. Oba derivata su relativno stabilna u neutralnoj, dok se u kiseloj sredini acil grupe hidrolizuju. Modifikacija alergena cis-akonitilovanjem i citrakonilovanjem može biti novi način za dobijanje alergoida.

House dust mites (HDM) represent a major source of allergens, contributing to the increasing incidence of type I hypersensitivity disease worldwide. Over 30 different IgE-binding proteins from the HDM extract were detected. Although group 1 and 2 have been identified as major allergens, due to the safety and efficacy of allergy diagnosis and immunotherapy, there is a need to carefully evaluate the clinical relevance of other allergens present in the HDM extract. In regard to this, a high molecular mass allergen of about 68 kD was purified from the HDM extract using a combination of gel permeation chromatography and reversed-phase chromatography. The IgG and IgE reactivity of the purified protein were preserved during the purification process, as confirmed by Western blot analysis with polyclonal rabbit antibodies and dot blot analysis with a pool of sera from subjects with house dust mite allergy, respectively. In addition, the IgE reactivity was confirmed using ELISA testing with nine patient sera. The biological potency of the 68 kD allergen was confirmed by skin prick testing in five allergic subjects, suggesting that the high molecular mass allergen is a good candidate for component-resolved diagnosis of house dust mite allergy and eventual therapeutic treatment. Grinje iz kućne prašine predstavljaju jedan od glavnih izvora alergena koji su u značajnoj meri doprineli porastu prvog tipa preosetljivosti. Preko 30 IgE-vezujućih proteina iz kućne prašine je detektovano do danas. Alergeni grupe 1 i 2 označeni su kao glavni alergeni kućne prašine. Međutim, da bi se poboljšala sigurnost i efikasnost dijagnoze i terapije alergijskih oboljenja izazvanih grinjama iz kućne prašine, neophodno je odrediti klinički značaj svih alergena iz ovog alergenskog izvora. U ovom radu izolovan je alergen visoke molekulske mase od 68 kD iz ekstrakta kućne prašine kombinovanjem gel-permeacione hromatografije i reversno-fazne hromatografije. IgG i IgE reaktivnost prečišćenog proteina je proverena u 'Western blot'-u i 'dot blot'-u sa poliklonskim zečijim antitelima na ekstrakt kućne prašine i 'pool'-om seruma osoba alergičnih na kućnu prašinu, redom. 64 % pacijenata je pokazalo IgE reaktivnost na prečišćeni protein u ELISA testu. Biološka reaktivnost prečišćenog alergena je potvrđena u kožnim probama na pet pacijenata, ukazujući da je prečišćen alergen dobar kandidat za dijagnozu alergije na kućnu prašinu pojedinačnim komponentama i eventualni terapeutski tretman.

Chemically modified allergens (allergoids) have found use in both traditional and novel forms of immunotherapy of allergic disorders. Novel forms of immunotherapy include local allergen delivery, via the gastrointestinal tract. This study conveys the gastrointestinal stability of three types of mugwort pollen allergoids under simulated conditions of the gut. Allergoids of the pollen extract of Artemisia vulgaris were obtained by means of potassium cyanate, succinic and maleic anhydride. Gastrointestinal tract conditions (saliva, and gastric fluid) were simulated in accordance with the EU Pharmacopoeia. The biochemical and immunochemical properties of the derivatives following exposure to different conditions were monitored by determining the number of residual amino groups with 2,4,6-trinitrobenzenesulfonic acid, SDS PAGE, immunoblotting and inhibition of mugwort-specific IgE. Exposure to saliva fluid for 2 min did not influence the biochemical and immunochemical properties of the derivatives. In the very acidic conditions of the simulated gastric fluid, the degree of demaleylation and desuccinylation, even after 4 h exposure, was low, ranging from 10 to 30 %. The digestion patterns with pepsin proceeded rapidly in both the unmodified and modified samples. In all four cases, a highly resistant IgE-binding protein the Mwof which was about 28-35 kD, was present. Within the physiological conditions, no new IgE binding epitopes were revealed, as demonstrated by immunoblot and CAP inhibition of the mugwort specific IgE binding. An important conclusion of this study is the stability of the modified derivatives in the gastrointestinal tract of patients, within physiological conditions. The means that they are suitable for use in much higher concentrations in local forms of immunotherapy than unmodified ones. U ovom radu su prikazani rezultati ispitivanja stabilnosti tri tipa alergoida polena pelina u simuliranom želudačnom soku. Koristeći kalijum-cijanat anhidrid ćilibarne i anhidrid maleinske kiseline, napravljeni su alergoidi polena pelina (Artemisia vulgaris). Saliva i želudačni sok su simulirani na osnovu evropske farmakopeje. Biohemijske i imunohemijske osobine derivata posle izlaganja različitim uslovima, praćene su: određivanjem broja slobodnih amino grupa u reakciji sa TNBS, SDS PAG elektroforezom, imunoblotom i određivanjem pelin-specifičnog imunoglobulina E (IgE). Izlaganje salivi u trajanju od 2 minuta ne utiče na biohemijske i imunohemijske osobine derivata. U kiseloj sredini želudačnog soka ne dolazi do značajnog demaleilovawa i desukcinilovanja. Čak i posle četvoročasovnog izlaganja, taj procenat je u opsegu 10-30 %. Alergoidi pelina se trenutno digestuju pepsinom, sa izuzetkom visoko rezistentne proteinske trake molekulske mase 28-35 kD, koja odgovara važnom IgE-vezujućem proteinu polena pelina. Imunoblotom i CAP-inhibicijom je pokazano da, u okviru fizioloških uslova, ne dolazi do stvaranja novih IgE-vezujućih epitopa. Hemijska stabilnost modifikovanih derivata u simuliranim uslovima želudačnog soka omogućuje da se tokom imunoterapije mogu primenjivati veće doze alergoida nego nemodifikovanog ekstrakta polena pelina.

Drug hypersensitivity syndrome is a severe form of hypersensitivity to the antiepileptic agent carbamazepine, particularly in presence of visceral and hematological manifestations that must be evidenced and treated in time. Two cases of female patients with carbamazepine-induced hypersensitivity syndrome are reported. Both patients had prominent general complaints (febricity, weakness). The first patient had leukopenia, lymphadenopathy and rash, while the other one had urticaria, angioedema and hepatitis after administration of carbamazepine. Hypersensitivity reactions induced by antiepileptics widely applied in the practice may be severe and life-threatening if blood elements are involved via the immune or nonimmune mechanisms and if they result in hepatitis.

This study considers the influence of exposure to simulated gastrointestinal conditions (saliva, gut, intestine and acidic conditions of the gut) on IgG binding of unmodified allergens and three types of LMW allergoids of Artemisia vulgaris pollen extract obtained by means of potassium cyanate succinic and maleic anhydride. It also concerns the optimization of a self-developed ELISA assay for comparison of the specific IgG binding of mugwort pollen extract and modified mugwort pollen derivatives. The ELISA was conducted with a mugwort pollen extract coupled to the plate, using the sera from 12 mugwort- pollen allergic patients. The exposure to saliva fluid for 2 min did not influence the IgG binding properties of allergens and allergoids. Exposure of mugwort pollen allergens and LMW allergoids to the acidic conditions of the gut did not dramatically change their IgG binding properties. By exposing mugwort pollen extract and LMW derivatives to the SGF conditions for 1 h, the percent of IgG binding epitopes was reduced to a half of its starting value in the extract and to about 30%in all the allergoid samples. After prolonged exposure only the carbamyl derivative showed reduced IgG binding. Changes of the IgG binding potential of all four samples after exposure in SIF followed a similar pattern. Predmet ovog rada je ispitivanje promena IgG vezivanja nemodifikovanih alergena polena A. vulgaris i tri tipa alergoida malih molekulskih masa dobijenih tretmanom sa kalijum-cijanatom, i anhidridima ćilibarne i meleinske posle izlaganja uslovima gastrointestinalnog trakta (saliva, želudac, tanko crevo i kisela sredina želudačnog soka) i optimizacija domaćeg ELISA testa za određivanje IgG vezivanja alergena i alergoida polena pelina.UELISA testu je za pločicu kuplovan ekstrakt polena pelina i korišćeni su serumi 12 pacijenata alergičnih na pelin. Izlaganje salivi u trajanju od 2 minuta ne utiče na IgG vezujuće osobine alergena i alergoida. Izlaganje kiseloj sredini želudačnog soka značajno ne utiče na IgG vezujuće osobine alergena i alergoida polena pelina. Posle izlaganja simuliranom želudačnom soku alergena i derivata u trajanju od 1 sata, procenat IgG vezujućih epitopa u nemodifikovanom uzorku se smanjuje na polovinu početne vrednosti i na oko 30 % kod sva tri derivata. Jedino se kod karbamil-derivata % IgG vezivanja dodatno smanjuje sa produžavanjem izlaganja SGF-u.Promene u IgG vezujućem potencijalu sva 4 uzorka posle izlaganja simuliranim uslovima tankog creva prate sličan obrazac.

According to the data obtained from in vivo and in vitro testing in Serbia, a significant number of patients have allergic symptoms caused by grass pollen. We examined the protein composition of grass pollens (Dactylis glomerata, Lolium perenne and Phleum pratense) and cross-reactivity in patients allergic to grass pollen from our region. The grass pollen allergen extract was characterized by SDS-PAGE, while cross-reactivity of single grass pollens was revealed by immunoblot analysis. A high degree of cross-reactivity was demonstrated for all three single pollens in the sera of allergic patients compared to the grass pollen extract mixture. Confirmation of the existence of cross-reactivity between different antigenic sources facilitates the use of monovalent vaccines, which are easier to standardize and at the same time prevent further sensitization of patients and reduces adverse reactions. [Projekat Ministarstva nauke Republike Srbije, br. 172049 i br. 172024]

Common ragweed (Ambrosia atremisiifolia) is one of the most frequent causes of pollen-induced allergic reactions both in humans and dogs. It has not been defined yet, what is the major allergen(s) to which most dogs allergic to ragweed show a positive result on intradermal skin test (IDST). In the present study sensitization to Ambrosia artemisiifolia pollen allergens in dogs with atopic dermatitis was examined with both in vivo and in vitro tests, including IDST and serum allergen specific IgE test. Detection of specific-IgE antibodies against ragweed allergens by immunoblotting in the sera of allergic dogs was optimized, as well. Dogs that were positive, as judged by IDST reactions to ragweed pollen allergens, also had alergen specific IgE antibodies in their sera. Results indicate that major allergens of A. artemisifolia pollen in dogs are Amb a 1 and Amb a 2. Further characterization of ragweed allergens is needed before they could potentially be used in intradermal testing or allergen immunotherapy in affected dogs. Also, we evaluated new Favrots diagnostic criteria for canine atopic dermatitis in dogs allergic to Ambrosia atremisiifolia pollen. It might be concluded that proposed criteria are of great assistance for seting up suspected diagnosis of canine atopic dermatitis, after ruling out other pruritic dermatoses. Kratka ambrozija (Ambrosia artemisiifolia) je jedan od najčešćih uzročnika alergijskih reakcija izazvanih polenom kod ljudi i pasa. Još uvek nije definisano koji je glavni alergen (i), na koji, većina pasa alergičnih na polen ambrozije, ispoljava pozitivnu reakciju na intradermalnom testu. U ovoj studiji je ispitana senzibilizacija na polen ove biljke kod pasa sa simptomima atopijskog dermatitisa in vivo i in vitro testovima, uključujući intradermalni test i dokazivanje prisustva alergen specifičnih IgE antitela u serumu. Optimizovani su uslovi za detekciju IgE specifičnih antitela iz seruma pasa alergičnih na polen ambrozije imunoblot tehnikom. Psi koji su imali pozitivnu reakciju na polen ove biljke na intradermalnom testu, takođe su imali specifična IgE antitela u serumu. Dobijeni rezultati ukazuju da su glavni alergeni Ambrosia artemisiifolia kod pasa Amb a 1 i Amb a 2. Neophodna je dalja karakterizacija alergena ambrozije kako bi se oni mogli primeniti pri rutinskom intradermalnom testiranju ili u alergen specifičnoj imunoterapiji obolelih pasa. Takođe je razmatrana i validnost Favrotovih dijagnostičkih kriterijuma kod pasa alergičnih na polen ambrozije. Može se zaključiti da su predloženi kriterijumi od velike pomoći u postavljanju suspektne dijagnoze atopijskog dermatitisa pasa, nakon isključenja drugih pruritičnih dermatoza.

Plant proteinase inhibitors are considered important defense molecules against insect and pathogen attack. The cysteine proteinase inhibitor (CPI) from green kiwifruit (Actinidia deliciosa) belongs to the cystatin family and shows potent antifungal activity (in vitro and in vivo). However, the low abundance of this molecule in fruit (6 mu g/g of fresh fruit) seems to limit further investigations on the interaction between phytocystatin and photopathogenic fungi. In this paper the cDNA of the kiwi CPI was expressed in Escherichia coli. Fifteen N-terminal amino acids were identified by Edman degradation, and 77% of the rCPI primary structure was confirmed by mass fingerprint. The structural homology of recombinant CPI (rCPI) to its natural counterpart has been clearly demonstrated in immunological assays (immunoblot and ELISA inhibition). Biological activity of rCPI was demonstrated in inhibition assay with cysteine proteinase papain (EC50 2.78 nM). In addition, rCPI reveals antifungal properties toward pathogenic fungi (Alternaria radicina and Botrytis cinerea), which designates it as an interesting model protein for the exploration of plant phytocystatins - pathogen interactions. Understanding the molecular mechanisms of natural plant resistance could lead to the development of ecologically safe fungicides for controlling post-harvest diseases and maintaining food quality.

Actinidin, an abundant cysteine protease from kiwifruit, is a specific biomarker of isolated allergy to kiwifruit. This study evaluates the IgE-binding properties of biologically active and thermally inactivated actinidin. Employing two different activity assays (caseinolytic assay and zymogram with gelatin) we showed that actinidin obtained from kiwifruit extract under native conditions represents a mixture of inactive and active enzyme. The structural integrity of actinidin was confirmed by SDS-PAGE. Edman degradation, mass fingerprint and Western blot with polyclonal antibodies. Although it was capable of inducing positive skin prick test reactions, we failed to detect IgE reactivity of active actinidin in Western blot with patient sera. Thermally inactivated actinidin exhibited IgE reactivity both in vivo and in vitro, indicating that heat processed kiwifruit products may induce clinical reactivity. These findings imply that apart from the allergenic epitopes on its surface, actinidin also contains hidden epitopes inside the protein which become accessible to IgE upon thermal treatment. (C) 2011 Elsevier Ltd. All rights reserved.

BACKGROUND: The major whey protein beta-lactoglobulin (BLG) has been widely studied for its functional properties. The aim of this study was to develop an efficient, inexpensive and rapid one-step method for the isolation and purification of BLG while preserving its native structure. RESULTS: BLGwas purified fromdefattedwheyobtainedfromrawcow's milkbyanionexchangechromatography. Protein purity and identitywere determined using reverse phase high-performance liquid chromatography andmass spectrometry. Total BLG yield was 80% with protein purity from 97 to 99%. BLG isoforms A and B were separated into fractions of 91 and 99% purity respectively. The structure and native conformation of the isolated BLGwere compared with those of standard commercial BLG by circular dichroism spectrometry, susceptibility to various crosslinking enzymes and enzyme-linked immunosorbent assay inhibition. CONCLUSION: Theproposedmethodis veryuseful for the rapid preparationofBLGsuitable for studying antigenicandmolecular characteristics of this protein, aswell as the effect of food processing on these properties. The procedure requires only 1 day for the purification of about 300 mgof BLG from a single run using a small column (2.5 cmx20 cm) of diethylaminoethyl Sephadex and has potential for scaling up. (C) 2011 Society of Chemical Industry This is the peer-reviewed version of the article: (1) Stojadinović, M. M.; Burazer, L. M.; Ercili-Cura, D.; Sancho, A.; Buchert, J.; Ćirković-Veličković, T.; Stanić-Vučinić, D. One-Step Method for Isolation and Purification of Native Beta-Lactoglobulin from Bovine Whey. Journal of the Science of Food and Agriculture 2012, 92 (7), 1432–1440. [https://doi.org/10.1002/jsfa.4722]. Published version: [https://cherry.chem.bg.ac.rs/handle/123456789/1275]

House dust mite (HDM) allergy has different clinical and immunological patterns in different geographic regions. The impact of raw material of commercial Dermatophadoides pteronyssinus (Acari: Pyroglyphidae) mite bodies on the quality of allergen extracts for allergy diagnosis in the Serbian population has not been previously evaluated. House dust mite bodies obtained from manufacturers in Europe, South America and Australia were used in the preparation of allergen extracts for in vivo diagnosis and serological analysis in a group of 14 HDM-allergic adults. In the group of mite-allergic patients, there was no statistically significant difference in skin test reactivity (Wilcoxon matched pairs test) among the three HDM body extract preparations. In a CAP inhibition assay, two extracts (A and C) achieved maximum inhibition of gt 90%, whereas extract B demonstrated a different inhibition slope and lower inhibition potential (80%). However, a remarkable difference in immunoglobulin E reactivity using Western blot analysis with individual patients' sera was observed in one of the preparations (extract B). These findings emphasize the need for the careful selection of starting material for the preparation of HDM diagnostic reagents intended for use in patients from geographically distinct regions as these preparations can have implications on the selection criteria for patient-tailored immunotherapy of HDM allergy.

Kiwifruit has become a frequent cause of fruit allergy in the recent years. The molecular basis of type I hypersensitivity to kiwifruit is attributed to 11 IUIS allergens, with Act d 1, Act d 2 and Act d 5 characterized in extenso. Evaluation of the allergenic properties of Act d 4, a cysteine proteinase inhibitor from green kiwifruit (Actinidia deliciosa) was performed in this study. Identity of the purified glycoprotein was determined by Edman degradation and by mass fingerprint whereby more than 90% of the primary structure of the mature kiwifruit cystatin was confirmed. Using MALDI TOF analysis, molecular masses of 10902.5 and 11055.2 Da were detected for Act d 4, respectively. Positive skin prick reactivity with Act d 4 was induced in three kiwifruit allergic patients, as well as the upregulation of CD63 and CD203c molecules in the basophile activation assay. The IgE reactivity was detected in dot blot analysis while Western blot analysis was negative using sera from six kiwifruit patients, suggesting the presence of conformational IgE epitopes on the Act d 4 molecule. As activator of effector cells in type I hypersensitivity Act d 4 is a functional allergen contributing to the clinical symptoms of kiwifruit allergy.

Treating allergies with modified allergens is an approach to make the treatment safer and more efficient. Art v 1 is the most prominent allergen of mugwort pollen and a significant cause of hayfever around Europe. The aim of this study was to reduce the allergenicity of Art v 1 by acetylation, and to investigate the capacity of the modified protein to generate blocking antibodies. The reduction of allergenicity of Art v 1 following acetylation was monitored by immunoblot, ELISA inhibition using a pool of sera from mugwort pollen allergic patients, basophil activation assay and by skin prick testing of mugwort-allergic patients. Rabbits were immunized against Art v 1 and acetylated Art v 1 (acArt v 1) and the rabbit antisera were tested for their capacity to block human IgE binding in ELISA. Human T cell proliferation against Art v 1 and acArt v 1 was examined in peripheral blood mononuclear cells (PBMCs) of mugwort pollen allergic patients and cytokine release in PBMC cultures was monitored. Acetylation of Art v 1 gave a derivative of reduced allergenicity in the in vitro and ex vivo tests applied. The skin test reactivity to acArt v 1 was significantly reduced in 19 patients when compared with the reactivity to Art v 1. Rabbit antibodies to acArt v 1 and Art v 1 showed similar capacity to block human IgE binding to Art v 1 in inhibition ELISA. Both proteins were able to induce proliferation of PBMCs and CD3/CD4(+) cells of mugwort-allergic patients. Release of IL-5 was significantly reduced in cultures stimulated with acArt v 1. Art v 1 modified by acetylation had a significantly reduced allergenicity in vitro and in vivo, while its immunogenicity was retained. Modification of allergens by acetylation could be a new strategy for allergen-specific immunotherapy. Cite this as: I. Perovic, M. Milovanovic, D. Stanic, L. Burazer, D. Petrovic, N. Milcic-Matic, G. Gafvelin, M. van Hage, R. Jankov and T. Cirkovic Velickovic, Clinical and Experimental Allergy, 2009 (39) 435-446.

The use of enzymes may improve the functional properties of various food ingredients. The aim of this study was to examine the effects of proteolytic contaminants in phenol oxidases on beta-lactoglobulin (BLG). In the presence of Trametes versicolor laccase and Agaricus bisporus tyrosinase, both variants of BLG (A and B) underwent removal of a peptide from the N-terminus. The truncated forms were more susceptible to digestion by pepsin. The truncation of BLG resulted from contaminating proteases and not due to the action of phenol oxidases. The removal of N-terminal peptides proceeded quickly, while the rest of the globular protein remained resistant to proteolysis for up to 3 h. In the case of the application of enzymes in food bioprocessing, it may be important to carefully monitor the effects of contaminating proteases in enzyme preparations used. (C) 2009 Elsevier Ltd. All rights reserved.

A simple ion-exchange HPLC-UV method was developed for determination of major allergens from mugwort pollen and kiwi fruit extracts in mass-units. The separation of Art v 1 and Act c 1 from other components in the extracts was achieved in one step. The extinction coefficients used in the study here theoretically determined and compared to the extinction coefficients determined by gravimetry. We also reported a close correlation of the major allergen contents with the overall allergenic potency of the extracts determined by inhibition ELISA. This method could be a useful tool for standardization of allergenic extracts for clinical use. (c) 2007 Elsevier B.V. All rights reserved.

Background: It is a general belief that a food allergen should be stable to gastric digestion. Various acidic plant polysaccharides, including pectin, are ubiquitous in fruit matrixes and can form hydrogels under low-pH conditions. Objective: The purpose of this study was to investigate the effect of hydrogel forming polysaccharide-rich fruit matrixes on in vivo gastric and in vitro pepsic digestion of fruit allergens. Methods: Fruit extract proteins (kiwi, banana, apple and cherry) and a purified major kiwi allergen Act c 2 were digested with simulated gastric fluid in accordance with the US Pharmacopeia. In vivo experiments on kiwi fruit digestion were performed on four healthy non-atopic volunteers by examining the gastric content 1 h after ingestion of kiwi fruit. The Act c 2 and kiwi proteins were detected in immunoblots using monoclonal anti-Act c 2 antibodies and rabbit polyclonal antisera. Results: Crude fruit extracts were resistant to digestion by pepsin when compared with commonly prepared extracts. In the gastric content of all volunteers, following kiwi fruit ingestion and immunoblotting, intact Act c 2 was detected with anti-Act c 2 monoclonal antibodies, while kiwi proteins of higher molecular weights were detected using rabbit polyclonal antisera. Addition of apple fruit pectin (1.5% and 3%) to the purified kiwi allergen was able to protect it from pepsin digestion in vitro. Conclusion: The matrix effect in pectin-rich fruits can influence the digestibility of food proteins and thereby the process of allergic sensitization in atopic individuals.

Background: Kiwi fruit allergy, as well as its association with hypersensitivity to other foods and to pollen, has been extensively reported in the last few years. Several IgE-binding components have been detected in kiwi extract, but only one 30-kd allergen has been isolated; it was identified as actinidin (Act c 1). Recently, we have reported a 24-kd kiwi protein to be a potential major allergen in a group of patients with oral allergy syndrome (OAS). Objective: The aim of this study was to purify and characterize the 24-kd kiwi allergen biochemically. Methods: Seven polysensitized patients with OAS to kiwi were used in this study. The kiwi allergen was isolated by using a combination of gel permeation, ion exchange, and immobilized metal ion affinity chromatography. Its biochemical characterization included determination of its isoelectric point, molecular weight, N-terminal sequencing, concanavalin A – binding ability, digestibility in simulated gastric fluid, and antifungal activity. Western blotting, 2-dimensional PAGE immunoblotting, and skin prick tests were performed to characterize the isolated protein immunochemically. Results: All 7 patients recognized the isolated 24-kd kiwi protein as an allergen. The isolated protein consisted of 2 isoforms with isoelectric points of 9.4 and 9.5 migrated as one protein band of 20 kd after SDS-PAGE under nonreducing conditions or at 24 kd under reducing conditions. The partial N-terminal sequence revealed that it is a thaumatin-like protein (TLP) with concanavalin A – binding ability. The protein showed antifungal activity toward Saccharomyces carlsbergensis , and Candida albicans . The protein was degraded by the simulated gastric fluid within 1 minute. Both isoforms bound IgE from a pool of sera in a 2-dimensional PAGE immunoblot. The TLP elicited positive skin prick test responses in 4 (80 % ) of 5 patients with OAS. Conclusion: This study reported isolation and full characterization of a new kiwi allergen, TLP (isoelectric points of 9.4 and 9.5 and molecular weight of 24 kd), which belongs to the family of pathogenesis-related proteins. The isolated protein expressed antifungal activity toward S carlsbergensis and C albicans . (J Allergy Clin Immunol 2002;110:805-10.)

Background: Reaction of e-amino groups of lysine with potassium cyanate, maleic, or succinic anhydride leads to allergoids of low molecular weight. No study has been performed to compare their properties and investigate the influence of a residual group on allergenicity and human IgE- and IgG-binding of these derivatives. Methods: Allergoids of a pollen extract of Artemisia vulgaris were obtained by means of potassium cyanate, and succinic and maleic anhydride. Biochemical properties were investigated by determination of amino groups, enzyme activity, isoelectric focusing IEF and SDS–PAGE. IgE- and IgG-binding was determined using immunoblots and ELISA inhibition. Allergenicity was investigated by skin prick tests (SPT) on a group of 52 patients, of which 6 were control subjects, 30 were patients with no previous immunotherapy (IT), and 16 were patients undergoing immunotherapy. Results: The same degree of amino-group modification (more than 85%), residual enzyme activity (less then 15%), IEF, and SDS–PAGE pattern were noted. In the immunoblots of IgE-binding, there was more pronounced reduction in the succinyl and maleyl derivatives than in the carbamyl one. IgG-binding was less affected by carbamylation than by acid anhydride modification. The SPT showed that the succinylated derivative had the most reduced allergenicity (98% showed a reduced wheal diameter when tested with the succinyl derivative, 87% with the maleyl allergoid, and 83% with the carbamyl allergoid). The most significant difference among allergoids could be seen in the group of patients with high skin reactivity (83% of patients showed no reaction to the succinyl derivative when compared to the value of 28% for the carbamyl derivative or 22% for the maleyl derivative). Conclusions: According to our results, all three modification procedures yielded allergoids with a similar extent of modification. No single biochemical parameter investigated in the study could predict the degree of reduced allergenicity in vivo. The most reduced allergenicity was seen in the succinyl derivative while the preservation of IgG binding epitopes was of the highest degree for the carbamyl derivative.

An association between pollution (e.g., from traffic emissions) and the increased prevalence of respiratory allergies has been observed. Field-realistic exposure studies provide the most relevant assessment of the effects of the intensity and diversity of urban and industrial contamination on pollen structure and allergenicity. The significance of in-depth post-translational modification (PTM) studies of pollen proteomes, when compared with studies on other aspects of pollution and altered pollen allergenicity, has not yet been determined; hence, little progress has been made within this field. We undertook a comprehensive comparative analysis of multiple polluted and environmentally preserved Phleum pratense (Timothy grass) pollen samples using scanning electron microscopy, in-depth PTM profiling, determination of organic and inorganic pollutants, analysis of the release of sub-pollen particles and phenols/proteins, and analysis of proteome expression using high resolution tandem mass spectrometry. In addition, we used quantitative enzyme-linked immunosorbent assays (ELISA) and immunoglobulin E (IgE) immunoblotting. An increased phenolic content and release of sub-pollen particles was found in pollen samples from the polluted area, including a significantly higher content of mercury, cadmium, and manganese, with irregular long spines on pollen grain surface structures. Antioxidative defense-related enzymes were significantly upregulated and seven oxidative PTMs were significantly increased (methionine, histidine, lysine, and proline oxidation; tyrosine glycosylation, lysine 4-hydroxy-2-nonenal adduct, and lysine carbamylation) in pollen exposed to the chemical plant and road traffic pollution sources. Oxidative modifications affected several Timothy pollen allergens; Phl p 6, in particular, exhibited several different oxidative modifications. The expression of Phl p 6, 12, and 13 allergens were downregulated in polluted pollen, and IgE binding to pollen extract was substantially lower in the 18 patients studied, as measured by quantitative ELISA. Quantitative, unrestricted, and detailed PTM searches using an enrichment-free approach pointed to modification of Timothy pollen allergens and suggested that heavy metals are primarily responsible for oxidative stress effects observed in pollen proteins. Keywords: Timothy grass pollen, Label free relative quantification, Oxidative post-translational modification, Air-related traffic pollution, Allergy, Heavy metal pollution