bluuebunny/crossref_metadata_2025_split huggingface dataset:
Colophony: an in vitro model for the induction of sensitization
Authors: Elms  , Allan  , Pengelly  , Fishwick  , Beckett  , Curran  
Published: March 2003

BackgroundThe potential of colophony fumes from soldering flux to induce asthma has been known since the 1970s, however, no direct in vitro or in vivo evidence has been reported. The present study investigated the potential of colophony to stimulate human phagocytic cells to produce reactive oxygen species.MethodsThe human cell line HL‐60 was differentiated to produce cells with a monocyte‐like and a neutrophil‐like phenotypes. A number of procedures were used to confirm the phenotype of these differentiated cells including morphology, esterase activity, flow cytometry and phagocytosis. The potential of colophony to stimulate human phagocytic cells to produce reactive oxygen species was monitored using flow cytoenzymology.ResultsWe were able to show that intracellular peroxide levels were increased in both monocyte‐like and neutrophil‐like cells, but not in undifferentiated HL‐60 cells following the addition of colophony.ConclusionsThe resin acid epoxides and hydroperoxides which have been suggested to be sensitizers in contact allergy, are degraded during the soldering process. However, conditions for the oxidation of colophony may occur in vivo as a result of the colophony‐induced oxidative burst from neutrophils and monocytes. These oxidation products may then interact with body proteins to further initiate immune responses. Therefore for the preparation of low molecular weight chemical (LMWC)–protein conjugates, consideration must be taken to determine whether the LMWC is undergoing a reaction in vivo before it is interacting with body proteins.
Is fungal α‐amylase in bread an allergen?
Authors: Sander  , Raulf‐Heimsoth  , Van Kampen  , Baur  
Published: March 2003

BackgroundThe enzyme α‐amylase from Aspergillus oryzae used in bakeries to improve the bread quality has been identified as an inhalative allergen in baker's asthma. It is doubtful whether this enzyme can induce allergic sensitization in regular bread consumers.ObjectiveTo find out whether fungal α‐amylase in bread and rolls retains its antibody‐binding capacity and allergenicity after the baking procedure.MethodsRabbit antibodies directed to fungal α‐amylase were used for the development of a two‐site enzyme‐linked immunosorbent assay (ELISA). This assay was used to analyse different fractions of bread and rolls baked with the usual amounts of α‐amylase in comparison with control products without added enzyme. Competitive experiments between bakers' sera containing specific immunoglobulin (Ig) E to α‐amylase and the rabbit antibodies were performed. Additionally, specific IgE binding to fungal α‐amylase was inhibited by native or heated α‐amylase.ResultsWith the highly specific two‐site ELISA for native α‐amylase in the crust of bread bottom and sides, 2.3–7 ng antigenic α‐amylase per gram crust were measured. No α‐amylase could be detected in the crumb fractions. Rabbit antibodies to native α‐amylase completely inhibited human IgE binding to α‐amylase allergen disks.ConclusionThe results prove residual antibody‐binding capacity of α‐amylase in bread crusts and in the crust of some rolls. In comparison with the content of α‐amylase in dough, between 0.1 and 20% of the antibody‐binding capacity remained.
Exposure and allergic sensitization to cockroach allergen in East Germany
Authors: Hirsch  , Stappenbeck  , Neumeister  , Weiland  , Von Mutius  , Keil  , Leupold  
Published: March 2003

BackgroundSome studies suggest that the prevalence of sensitization to cockroach allergens may be higher in the United States than in Europe, but there are no comparable data from population‐based studies.ObjectivesTo determine the prevalence of allergic sensitization to German cockroach (GCR) in German schoolchildren and to assess its clinical relevance; and to determine the exposure to the major GCR allergen Bla g 2 in non‐selected homes and nurseries.MethodsThe prevalence of allergic sensitization to GCR and other allergens was determined by measurement of specific IgE and skin‐prick tests in a cross‐sectional study of 2993 children aged 5–11 years in Dresden, Germany. The prevalence of atopic disease was determined by questionnaire, and pulmonary function and bronchial hyperresponsiveness to hypertonic saline were measured. Bla g 2 exposure was determined on floors of 187 kitchens and 47 nurseries by a commercial sandwich ELISA.ResultsOne hundred and twenty‐seven (4.2%) of the children had specific IgE (> 0.7 kU/L) against GCR. Among children with current wheeze, 8.4% were GCR‐sensitized. Compared to data from the United States, the prevalence of sensitization to cockroach was similar in children without asthma (3.9%), but less frequent in asthmatic children from Dresden (6.1%). After adjustment for positive reactions to other allergens (SX1 test) no significant impact of GCR sensitization on wheeze or other symptoms and diagnoses was found. Bla g 2 was detected in 29% of the kitchens and 43% of the nurseries. None of these sites had exposure levels above the proposed threshold for causing disease of 80 ng/g dust.ConclusionThe data suggest that allergic sensitization to GCR is less frequent in asthmatics from Dresden, Gemany than in US cities. The data indicate that GCR sensitization is not an independent risk factor for asthma and other atopic diseases in 5–11‐year‐olds from this city.
Der p 1 and Der f 1, the highly related and major allergens from house dust mites, are differentially affected by a plant cystatin
Authors: Pernas  , Sanchez‐Ramos  , Sanchez‐Monge  , Lombardero  , Arteaga  , Castañera  , Salcedo  
Published: March 2003

BackgroundDer p 1 and Der f 1 are highly related allergens from the two main house dust mite species, Dermatophagoides pteronyssinus and Dermatophagoides farinae, respectively. A link between the cysteine proteinase activity of Der p 1 and its allergenicity has recently been demonstrated.ObjectiveTo test the effects of several proteinase inhibitors, mainly a chestnut cystatin (CsC), on the enzymatic activity of Der p 1 and Der f 1, as well as to study the potential acaricide properties of the inhibitors.MethodsInhibition tests were performed using mite extracts, as well as isolated Der p 1 and Der f 1 as targets. Immunodetection after SDS‐PAGE and N‐terminal amino acid sequencing were used to demonstrate the inactivation of chestnut cystatin by Der p 1. Bioassays including different inhibitors in a semisynthetic diet were performed to evaluate a potential effect on larval survival.ResultsCsC inhibited the crude digestive proteinase activity of D. farinae, but it was not active towards the equivalent enzyme from D. pteronyssinus. This differential behaviour was fully explained by testing CsC against the two purified allergens, Der f 1 and Der p 1; the former was highly susceptible, whereas the latter was not affected. In contrast, other cysteine proteinase inhibitors, such as egg white cystatin and E‐64, inhibited the proteinase activity of both mite allergens. Der p 1 inactivated CsC by a specific proteolytic cleavage between Gly 6 and Val 7, thus given rise to a noninhibitory processed protein. Besides the in vitro activity, CsC also showed an in vivo effect on D. farinae, drastically increasing the larval mortality when added to a semisynthetic diet.ConclusionDer p 1 and Der f 1 behave very differently towards a plant cystatin, thus indicating substantial differences in their proteolytic activity. This fact could be significant with regards to the immunogenic properties of both allergens.
Comparison of genetically engineered hypoallergenic rBet v 1 derivatives with rBet v 1 wild‐type by skin prick and intradermal testing: results obtained in a French population
Authors: Pauli  , Purohit  , Oster  , De Blay  , Vrtala  , Niederberger  , Kraft  , Valenta  
Published: March 2003

BackgroundBet v 1, the major allergen in birch pollen, is recognized by more than 90% of patients allergic to birch in northern and central Europe. Immunotherapy is commonly performed with birch pollen extracts. Recently, hypoallergenic derivatives of Bet v 1 (rBet v 1 fragments, rBet v 1 dimer and trimer) were constructed and purified.ObjectiveOur aim was to compare the allergenic activity of wild‐type rBet v 1 with recombinant Bet v 1 derivatives (rBet v 1 fragments, dimer and trimer) with potentially reduced anaphylactic activity by skin testing in a French population.MethodsAmong the 36 birch pollen allergic patients included in the study, 29 were tested by skin prick testing and 30 by intradermal injections with purified monosubstances: rBet v 1 fragments (F1: aa1–74 and F2: aa75–160), Bet v 1 dimer and trimer. Intradermal tests were performed by the end‐point intradermal titration method. Eight of the intradermally‐tested patients were previously hyposensitized. Tests were performed over a period of 6 months (before, during and after birch pollen season); Bet v 1‐specific IgE and IgG4 subclass responses were measured by immunoblotting and ELISA.ResultsAll patients showed lower reactivity with the modified rBet v 1 allergens, both in skin prick and intradermal tests. In 25 and 23 out of 29 patients the lowest concentration of fragment 1 and 2, respectively, resulting in a positive prick test was 100‐fold higher than the lowest concentration of monomer resulting in a positive prick test. For dimer it was 100‐fold or more in 25 out of 29 patients, and for trimer it was 100‐fold or superior in 26 out of 29 patients. By intradermal testing, the end‐point concentration was 160‐fold higher for trimer than for monomer in 24 patients and 40‐fold higher in five patients. For the two fragments the end‐point concentration was 160‐fold higher in 20 out of 22 patients.ConclusionGenetically modified hypoallergenic derivatives of the major birch pollen allergen, Bet v 1 showed reduced capacity to induce immediate type skin reactions. They may represent candidate molecules for immunotherapy of birch pollen allergy with reduced risk of anaphylactic side‐effects.
Recombinant Hev b 1: large‐scale production and immunological characterization
Authors: Rihs  , Chen  , Schumacher  , Rozynek  , Cremer  , Lundberg  , Raulf‐Heimsoth  , Petersen  , Baur  
Published: March 2003

BackgroundHev b 1 represents one of the most important allergens in Hevea brasiliensis latex. It is difficult to get an appropriate amount of native Hev b 1 (nHev b 1) for research purposes.ObjectiveThe aim of this study was to produce sufficient amounts of Hev b 1 by recombinant methods to prove its suitability for latex allergy diagnostics.MethodsWe isolated total RNA of Hevea brasiliensis leaves and synthesized cDNA by RT PCR. Recombinant Hev b 1 (rHev b 1) as well as three fragments (amino acid residues 29–137, 48–137, 78–137) were subcloned and expressed as fusion proteins with Maltose‐binding protein (MBP) in Escherichia coli. The MBP‐rHev b 1 fusion protein was examined by RAST with the CAP method, histamine release test and immunoblots with human sera from spina bifida patients as well as from health care workers with latex allergy and monoclonal antibodies.ResultsHistamine release test and immunoblots revealed the high allergenicity of the MBP‐rHev b 1 construct. By the CAP method, 54 out of 58 serum samples (93%) from latex‐sensitized spina bifida patients previously showing immunoglobulin (Ig) E to nHev b 1 exhibited IgE‐binding to rHev b 1. Among 71 latex‐allergic health care workers tested, 16 (22.5%) had IgE antibodies to rHev b 1. The analysis of the fusion proteins carrying rHev b 1 fragments revealed that the loss of the N‐terminal 28 amino acid residues did not affect IgE‐binding. In contrast, the lack of the first 47 amino acid residues led to decreased IgE‐binding reactivity in two out of four sera tested, whereas the absence of the N‐terminal 77 residues abolished IgE‐binding in these two sera.ConclusionThe MBP‐rHev b 1 fusion protein exhibits a corresponding IgE‐binding reactivity to nHev b 1 and may therefore substitute natural Hev b 1 for both in vitro diagnostics and research purposes.
Reduced IFNγ production in response to IL‐12 stimulation and/or reduced IL‐12 production in atopic patients
Authors: Matsui  , Kaneko  , Teramoto  , Fukao  , Inoue  , Kasahara  , Takemura  , Seishima  , Kondo  
Published: March 2003

BackgroundSeveral studies have shown that interleukin (IL)‐4 and interferon‐gamma (IFNγ) are important for the regulation of IgE production and that IL‐12 induces IFNγ.ObjectiveIFNγ production in response to IL‐12 stimulation and IL‐12 production were investigated in peripheral blood mononuclear cells (PBMCs) of atopic patients with various levels of serum IgE.MethodsCytokine production from PBMCs was measured following stimulation with a nonspecific stimulator (phytohemagglutinin: PHA), a specific stimulator (Der f 1) and IL‐12 in 17 healthy controls and 23 atopic patients with various serum IgE levels.ResultsThe IFNγ production by IL‐12‐stimulated PBMCs in the atopic group was lower than that in the control group. Furthermore, the serum IgE level was negatively correlated with IFNγ production by PBMCs stimulated with IL‐12 (P < 0.001), and with IL‐12 production by PBMCs stimulated with Der f 1 (P < 0.001). Although the IFNγ concentrations by PHA‐stimulated PBMCs were correlated with those by IL‐12‐stimulated PBMCs, there were differences in several patients.ConclusionsOur results indicated that atopic patients may have some abnormality in the IL‐12‐IFNγ loop. It was shown that the elevation in IgE levels in atopic patients may be due to reduced IFNγ production in response to IL‐12 stimulation and/or due to reduced IL‐12 production.
A moderate and unspecific release of cysteinyl leukotrienes by aspirin from peripheral blood leucocytes precludes its value for aspirin sensitivity testing in asthma
Authors: Pierzchalska M. , Mastalerz L. , Sanak M. , Zazula M. , Szczeklik A. 
Published: March 2003

Aspirin‐induced asthma (AIA) is a clinical syndrome related to cysteinyl leukotriene overproduction in airways. The confirmation of the diagnosis requires inconvenient provocation tests with acetyl salicylic acid (ASA).A study was performed to evaluate whether measurement in vitro of cysteinyl leukotrienes (cys‐LTs) release by isolated peripheral blood leucocytes, stimulated with ASA, can be of use for diagnosis of AIA.A cellular allergen stimulation test, CAST, was adapted to measure leukotriene release from leucocytes of 32 aspirin‐tolerant and 26 aspirin‐intolerant asthmatics. The cells were stimulated with Lys‐ASA, N‐formyl‐methionyl‐leucyl‐phenylalanine (fMLP), or both fMLP and Lys‐ASA, in a buffer containing IL‐3, and results compared with human leukaemia cell line (Hl‐60) response to Lys‐ASA. Cys‐LTs were measured in cell supernatant fluids by ELISA.ASA had a rather week stimulatory effect on cys‐LTs release in both groups of patients. Contrary to some previous studies, no significant differences were found between cys‐LTs release by leucocytes from AIA and ATA, or by differentiated Hl‐60 cells.Measurement of cysteinyl‐leukotriene release by peripheral blood leucocytes pre‐treated with aspirin has no value for diagnosis of AIA.
Microflora‐associated characteristics in faeces from allergic and nonallergic infants
Authors: Böttcher M. F. , Nordin E. K. , Sandin A. , Midtvedt T. , Björkstén B. 
Published: March 2003

Background The prevalence of allergic diseases has increased particularly over the past 30–40 years. A reduced microbial stimulation during infancy may result in a development of a disturbed balance between Th1‐ and Th2‐like immunity. The gut flora is, quantitatively, the most important source for such stimulation.Objective The aim of the study was to compare the gut microbial flora in 25 allergic and 47 nonallergic 13‐month‐old infants (range 11–18), through analysing microflora‐associated biochemical markers in faeces.Methods Microflora associated characteristics (MACs) were assessed by determining the concentrations of eight different short chain fatty acids and the conversion of cholesterol to coprostanol by gas chromatography. Faecal tryptic activity was analysed spectrophotometrically.Results The allergic infants had lower levels of propionic, i‐butyric, butyric, i‐valeric and valeric acid. In contrast, they had higher levels of the rarely detected i‐caproic acid, which has been associated with the presence of Clostridium difficile. Furthermore, the allergic infants had higher relative distribution of acetic and i‐caproic acid. None of the other parameters differed between the groups.Conclusion The results demonstrate differences in the MACs between allergic and nonallergic infants, indicating differences in the composition of the gut flora that may disturb the development of a normal Th1‐/Th2‐balance in allergic children.
Biologically active recombinant forms of a major house dust mite group 1 allergen Der f 1 with full activities of both cysteine protease and IgE binding
Authors: Yasuhara T. , Takai T. , Yuuki T. , Okudaira H. , Okumura Y. 
Published: March 2003

Background Group 1 allergens from mite faeces, Der f 1 and Der p 1, are the most significant in‐door allergens. Therefore, they are the most important component in the standardization of house dust mite extract for diagnosis and allergen‐specific immunotherapy (AIT). Although their cDNAs have been cloned, efforts to prepare biologically active recombinant forms in expression systems using bacteria or yeast have failed.Objective Our purpose is to establish an efficient system to prepare recombinant Der f 1(rDer f 1), identical in quality to native Der f 1.Methods The preproforms of Der f 1 and a mutant N53Q, whose consensus motif for N‐glycosylation was disrupted, were expressed in yeast Pichia pastoris. Cysteine protease activity and IgE reactivity were analysed using synthetic substrates and by RAST‐EIA, respectively.Results The proforms of the two rDer f 1 molecules were efficiently secreted into culture medium. Their prosequences were removed autocatalytically by dialysis against acidic buffer. Although the wild‐type rDer f 1 was more highly glycosylated than native Der f 1, N53Q had almost the same apparent molecular weight as native Der f 1 on SDS‐PAGE. Both the protease and IgE binding activities of the mature rDer f 1 molecules were the same as those of native Der f 1, whereas the proforms had no or markedly reduced activities.Conclusion The efficient system to prepare active rDer f 1s established in this study is useful for diagnosis and standardized AIT for house dust mite allergy. Furthermore, the system would be a tool for analysis of IgE epitopes, determination of tertiary structure, allergen engineering for safer and more effective AIT, resolving the relation between the enzymatic activity and pathogenesis, and the development of therapeutic inhibitors.
Identification of some rabbit allergens as lipocalins
Authors: Baker J. , Berry A. , Boscato L. M. , Gordon S. , Walsh B. J. , Stuart M. C. 
Published: March 2003

Rabbits are frequently used as laboratory animals or kept as domestic pets. Rabbit serum albumin and a 17‐kDa protein referred to as Ory c 1 have previously been reported as allergens. Several other allergenic proteins have been recognized by crossed immuno‐electrophoresis but have not been characterized.The aim of this study was to characterize the allergenic proteins present in rabbit saliva, urine and fur on the basis of molecular size and, where possible, to determine their amino acid sequences.Extracts from the male New Zealand white rabbit were used for developing specific direct RAST and RAST inhibition assays. Proteins in the extracts were separated by SDS‐PAGE and the individual allergens identified by immunoblotting with serum from rabbit‐allergic individuals. The N‐termini of four allergens were sequenced.Saliva was the most potent extract. In total, 26 protein bands were recognized as allergens in the three extracts: 12 in saliva, seven in urine and seven in fur. Their molecular weights ranged from an 8‐kDa species in saliva to an 80‐kDa protein in urine. The N terminal sequences of an 18 kDa and a 21‐kDa species in saliva, were identified as lipocalins with sequence similarity to a recently described odourant binding protein.This is the first evidence that allergens from the rabbit are members of the lipocalin superfamily of proteins, suggesting that similar mechanisms may be involved in eliciting the allergic response to rabbits. The 18 kDa allergen from saliva may be the previously named rabbit allergen, Ory c 1.
Diagnostic value of skin‐prick and patch tests and serum eosinophil cationic protein and cow's milk‐specific IgE in infants with cow's milk allergy
Authors: Saarinen K. M. , Suomalainen H. , Savilahti E. 
Published: March 2003

The diagnosis of cow's milk allergy is based on a clinical response to an elimination‐challenge test with cow's milk.We studied the usefulness of the skin‐prick and patch tests and measurement of cow's milk‐specific IgE and eosinophil cationic protein in serum as diagnostic tools for cow's milk allergy in a cohort of 6209 unselected infants followed from birth for the development of cow's milk allergy.Of the 239 infants challenged with cow's milk, 118 showed a positive and 121 a negative response at a mean age of 6.9 months. A positive reaction to a skin‐prick test with cow's milk ( 3 mm) was seen in 72 (61%) and 29 (24%) infants with positive and negative challenges, elevated serum cow's milk‐specific IgE ( 0.7 kU/L) in 52 (45%) and 15 (13%) infants, a positive reaction to patch test with cow's milk protein fractions in 26 (26%) and eight (8%) infants, and elevated serum eosinophil cationic protein ( 20 μg/L) in 22 (21%) and seven (13%) infants, respectively. Parallel use of the four tests with the above‐mentioned cut‐off values correctly classified 73% of the infants with a sensitivity of 0.76 and a specificity of 0.67. An immediate reaction to cow's milk challenge correlated with skin prick test positivity and elevated serum milk‐specific IgE, and tended to correlate with patch test positivity.No single test or parallel use of the four tests could predict the challenge outcome acceptably in this prospectively followed, unselected cohort of 6209 infants. A positive reaction to one or more tests needs to be confirmed by a challenge test and a negative response to all four tests does not rule out the possibility of cow's milk allergy.