59 research outputs found

    Optimization of the heterologous expression of banana glucanase in Escherichia coli (vol 77, pg 43, 2012)

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    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 production of the protein induced by 1 mM isopropyl-beta-D-thiogalactopyranoside (IPTG). The conditions for protein expression were optimized by varying the temperature (25, 30 and 37 C) and duration of protein expression (3, 6 and 12 h). The level of protein production was analyzed by densitometry of the sodium dodecyl sulfate-polyacrylamide gel (SDS-PAG) after electrophoretic resolution of the respective cell lysates. The optimal protein expression for downstream processing was obtained after 12 h of cell growth at 25 degrees 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 the rGST-Mus a 5 was confirmed by dot blot analysis with sera of individual patients from subjects with banana allergy and polyclonal rabbit antibodies against banana extract, respectively. The purified recombinant glucanase is a potential candidate for banana allergy diagnosis.Za potrebe proizvodnje u Escherichia coli gen glukanaze iz banane (GenBank GQ268963) je ukloniran u ekspresioni vektor pGEX-4T sa glutation-S-transferazom (GST). Proizvodnja ovog proteina u ćelijama je indukovana 1 mM izopropil-Ī²-D-tiogalaktopiranozidom (IPTG). Uslovi za ekspresiju proteina su optimizovani variranjem temperature (25, 30 i 37Ā°C) i dužine trajanja proteinske sinteze (3, 6 i 12 h). Nivo proizvodnje proteina je analiziran denzitometrijom SDS-PA gela nakon elektroforetskog razdvajanja ćelijskih lizata. Optimalna proizvodnja proteina za njegovo dalje procesovanje je dobijena gajenjem ćelija nakon dodatka IPTG na 25Ā°C tokom 12 h. Rekombinantni GST-Mus a 5 prečiŔćen afinitetnom hromatografijom sa glutationom pokazuje molekulsku masu od 60 kDa. IgE i IgG reaktivnost izolovane glukanaze potvrđena je u 'dot blot' sa pojedinačnim serumima osoba alergičnih na bananu, i sa poliklonskim zečijim antitelima na ekstrakt banane, redom. PrečiŔćena rekombinantna glukanaza je potencijalan kandidat za dijagnozu alergije na bananu

    Optimizacija heterologe proizvodnje glukanaze iz banane u E. coli

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    For the heterologous production of a banana glucanase in Escherichia coli, its gene (GenBank GQ268963) was cloned into a pG EX-4T expression vector as a fusion protein with glutathione-S-transferase (GST). BL21 cells transformed with the GST-Mus a 5 con struct were employed for production of the protein induced by 1 mM isopropyl-Ī²-D-thiogalactopyranoside (IPTG). The conditions for protein expression were optimized by varying the temperature (25, 30 and 37Ā°C) and duration of protein expression (3, 6 and 12 h). The level of protein production was analyzed by densitometry of the sodium dodecyl sulfate-polyacrylamide gel (SDS-PAG) after electrophoretic resolution of the respective cell lysates. The optimal protein expression for downstream processing was obtained after 12 h of cell growth at 25Ā°C upon addition of IPTG. Recombinant GST-Mus a 5 purified by glutathione affinity chromatography revealed a molecular mass of a bout 60 kDa. The IgE and IgG reactivity of the rGST-Mus a 5 was confirmed by dot blot an analysis with sera of individual patients from subjects with banana allergy and polyclonal rabbit antibodies against banana extract, respectively. The purified recombinant glucanase is a potential candidate for banana allergy diagnosis.Za potrebe proizvodnje u Escherichia coli gen glukanaze iz banane (GenBank GQ268963) je ukloniran u ekspresioni vektor pGEX-4T sa glutation-S-transferazom (GST). Proizvodnja ovog proteina u ćelijama je indukovana 1 mM izopropil-Ī²-D-tiogalaktopiranozidom (IPTG). Uslovi za ekspresiju proteina su optimizovani variranjem temperature (25, 30 i 37Ā°C) i dužine trajanja proteinske sinteze (3, 6 i 12 h). Nivo proizvodnje proteina je analiziran denzitometrijom SDS-PA gela nakon elektroforetskog razdvajanja ćelijskih lizata. Optimalna proizvodnja proteina za njegovo dalje procesovanje je dobijena gajenjem ćelija nakon dodatka IPTG na 25Ā°C tokom 12 h. Rekombinantni GST-Mus a 5 prečiŔćen afinitetnom hromatografijom sa glutationom pokazuje molekulsku masu od 60 kDa. IgE i IgG reaktivnost izolovane glukanaze potvrđena je u 'dot blot' sa pojedinačnim serumima osoba alergičnih na bananu, i sa poliklonskim zečijim antitelima na ekstrakt banane, redom. PrečiŔćena rekombinantna glukanaza je potencijalan kandidat za dijagnozu alergije na bananu

    Allergenic potency of kiwi fruit during fruit development

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    Food allergies, including kiwi fruit allergy, have been the subject of extensive research in the last few years. The aim of this study was to examine a possible relationship between the developmental stage of kiwi fruit and its allergenic potency. The protein and allergen patterns of kiwi fruit extracts in September, October, November and December fruit in the period from 2000-2002 were analysed. One of the factors that may contribute to the difficulties in proposing well-defined and standardized fruit extracts should also be the time of fruit harvesting. In this particular case, when the kiwi fruit was edible throughout November and December, we showed discrepancies in allergen content and potencies both in qualitative and quantitative terms. Two major allergens of kiwi fruit, Act c 1 and Act c 2, mainly accounted for the highest allergenic potential of November kiwi extract in vivo and in vitro. Not only the content of major allergens, but also the ratio of different proteins and even isoforms of the same allergen (Act c 2) change with fruit ripening. These findings should be taken into account during preparation of extracts for allergy diagnosis

    Izolovanje i karakterizacija 68 kD alergena iz ekstrakta kućnih grinja

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    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 praÅ”ine predstavljaju jedan od glavnih izvora alergena koji su u značajnoj meri doprineli porastu prvog tipa preosetljivosti. Preko 30 IgE-vezujućih proteina iz kućne praÅ”ine je detektovano do danas. Alergeni grupe 1 i 2 označeni su kao glavni alergeni kućne praÅ”ine. Međutim, da bi se poboljÅ”ala sigurnost i efikasnost dijagnoze i terapije alergijskih oboljenja izazvanih grinjama iz kućne praÅ”ine, 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 praÅ”ine kombinovanjem gel-permeacione hromatografije i reversno-fazne hromatografije. IgG i IgE reaktivnost prečiŔćenog proteina je proverena u 'Western blot'-u i 'dot blot'-u sa poliklonskim zečijim antitelima na ekstrakt kućne praÅ”ine i 'pool'-om seruma osoba alergičnih na kućnu praÅ”inu, redom. 64 % pacijenata je pokazalo IgE reaktivnost na prečiŔćeni protein u ELISA testu. BioloÅ”ka reaktivnost prečiŔćenog alergena je potvrđena u kožnim probama na pet pacijenata, ukazujući da je prečiŔćen alergen dobar kandidat za dijagnozu alergije na kućnu praÅ”inu pojedinačnim komponentama i eventualni terapeutski tretman

    Digestomics of Cow's Milk: Short Digestion-Resistant Peptides of Casein Form Functional Complexes by Aggregation

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    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

    Rana alergijska reakcija na metilprednizolon sa tolerancijom drugih kortikosteroida

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    Introduction. In spite of the wide usage of corticosteroids for the treatment of a plethora of diseases, sometimes they can induce immediate hypersensitivity reactions, which are however uncommon. Case Outline. We report a case of immediate allergic reaction induced by intravenous methylprednisolone given before operation for surgical repair of an arm contracture as a sequel of burns, which the child had tolerated a month before. Six weeks later the patient repeated the anaphylactic reaction during skin testing to methylprednisolone. In addition, basophile activation test with methylprednisolone (BAT) was positive. Conclusion. This case report describes a patient who experienced intraoperative anaphylaxis and anaphylactic reaction induced by skin testing. This is the first report on induction of both anaphylactic reactions by methylprednisolone in the same child. Clinical findings, positive BAT and positive skin tests with methylprednisolone imply that the child developed type-I hypersensitivity. The lack of cross-reactivity with other corticosteroids emphasizes that the reactions were caused by the steroid molecule.Uvod. Uprkos Ŕirokoj primeni kortikosteroida u lečenju od različitih bolesti, oni ponekad mogu izazvati ranu alergijsku reakciju. Prikaz bolesnika. Kod dvanaestogodiŔnjeg dečaka doŔlo je do rane alergijske reakcije izazvane intravenskom primenom metilprednizolona neposredno pre hirurŔke intervencije, tačnije, korekcije kontrakture Ŕake koja se javila kao komplikacija opekotine. Mesec dana pre pojave alergijske reakcije dete je primalo metilprednizolon i dobro ga podnosilo. Šest nedelja posle operacije ponovo se javila anafilaktička reakcija tokom kožnog testiranja metilprednizolonom. Primenjen je i test aktivacije bazofila (BAT) ovim lekom, čiji je nalaz bio pozitivan. Zaključak. Ovo je prvi prikaz dve vrste anafilaktičke reakcije izazvane metilprednizolonom kod iste osobe. Klinička slika, pozitivni nalaz BAT i pozitivne kožne probe na metilprednizolon pokazuju da se kod deteta razvio prvi tip hipersenzitivne reakcije. Nedostatak unakrsne reaktivnosti s ostalim kortikosteroidima ukazuje na to da je alergijska reakcija izazvana steroidnim molekulom

    Izolovanje i karakterizacija 68 kD alergena iz ekstrakta kućnih grinja

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    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 praÅ”ine predstavljaju jedan od glavnih izvora alergena koji su u značajnoj meri doprineli porastu prvog tipa preosetljivosti. Preko 30 IgE-vezujućih proteina iz kućne praÅ”ine je detektovano do danas. Alergeni grupe 1 i 2 označeni su kao glavni alergeni kućne praÅ”ine. Međutim, da bi se poboljÅ”ala sigurnost i efikasnost dijagnoze i terapije alergijskih oboljenja izazvanih grinjama iz kućne praÅ”ine, 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 praÅ”ine kombinovanjem gel-permeacione hromatografije i reversno-fazne hromatografije. IgG i IgE reaktivnost prečiŔćenog proteina je proverena u 'Western blot'-u i 'dot blot'-u sa poliklonskim zečijim antitelima na ekstrakt kućne praÅ”ine i 'pool'-om seruma osoba alergičnih na kućnu praÅ”inu, redom. 64 % pacijenata je pokazalo IgE reaktivnost na prečiŔćeni protein u ELISA testu. BioloÅ”ka reaktivnost prečiŔćenog alergena je potvrđena u kožnim probama na pet pacijenata, ukazujući da je prečiŔćen alergen dobar kandidat za dijagnozu alergije na kućnu praÅ”inu pojedinačnim komponentama i eventualni terapeutski tretman

    Digestibilnost alergoida polena pelina u simuliranim uslovima gastrointestinalnog trakta

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    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 fizioloÅ”kih 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
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