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Keywords: allergens; food allergy; IgE; IgG4; peanut EN allergens food allergy IgE IgG4 peanut 1835 1836 2 07/14/20 20200701 NES 200701 To the Editor, Mose et al1 reopened the discussion on bioavailability of digestion-stable food allergens in human. Their paper elegantly shows that peanut allergen can be detected in serum, minutes to hours following peanut consumption by healthy subjects. [Extracted from the article]

In this paper, we have determined the levels of IgG1 and IgG4 anti-IgE in the sera of 66 asthma patients suffering from mild (n= 24), moderate (n= 23), or severe (n= 19) symptoms, and 20 nonatopic, healthy subjects. The study has revealed that although asthma patients have significantly elevated levels of IgG1 and IgG4 anti-IgE antibodies, the concentration of these autoantibodies is not related to the severity of asthma. This conclusion may be related to the known heterogeneity of autoanti-IgE antibodies in terms of their ability to trigger basophil histamine release. [ABSTRACT FROM AUTHOR]

The article presents abstracts of various research papers to be presented in a conference to be held on September 14, 1993. One of the abstracts is on atopic allergy, which is causally related with selective activation of allergen-specific T helper type 2 (Th2) cells, which produce high amounts of interleukin (IL)-4 and IL-5. The aim of the study is to identify the factors, present during the differentiation of T helper cells that lead to selective outgrowth of Th2 cells. Another abstract is on neuroendocrine peptides which are involved in the regulation of effector cells of allergy. These peptides can also inhibit immunoglobuline synthesis but no data are available concerning human immunoglobulin (Ig) E. Neuroendocrine peptides endogenously modulate human in vitro IgE synthesis and represent eventually the postulated neuroendocrine arm in diseases like atopic dermatitis.

Background: Allergen source‐derived proteases are a critical factor in the formation and development of asthma. The cysteine protease activity of house dust mite (HDM) disrupts the epithelial barrier function. The expression of cystatin SN (CST1) is elevated in asthma epithelium. CST1 inhibits the cysteine protease activity. We aimed to elucidate the role of epithelium‐derived CST1 in the development of asthma caused by HDM. Methods: CST1 protein levels in sputum supernatants and serum of patients with asthma and healthy volunteers were measured by ELISA. The ability of CST1 protein to suppress HDM‐induced bronchial epithelial barrier function was examined in vitro. The effects of exogenous CST1 protein on abrogating HDM‐induced epithelial barrier function and inflammation were examined in mice in vivo. Results: CST1 protein levels were higher in sputum supernatants (142.4 ± 8.95 vs 38.87 ± 6.85 ng/mL, P < 0.0001) and serum (1129 ± 73.82 vs 703.1 ± 57.02 pg/mL, P = 0.0035) in patients with asthma than in healthy subjects. The levels were significantly higher in patients with not well‐ and very poorly controlled asthma than those with well‐controlled asthma. Sputum and serum CST1 protein levels were negatively correlated with lung function in asthma. CST1 protein levels were significantly lower in the serum of HDM‐specific IgE (sIgE)‐positive asthmatics than in sIgE‐negative asthmatics. The HDM‐induced epithelial barrier function disruption was suppressed by recombinant human CST1 protein (rhCST1) in vitro and in vivo. Conclusion: Our data indicated that human CST1 protein suppresses asthma symptoms by protecting the asthmatic bronchial epithelial barrier through inhibiting allergenic protease activity. CST1 protein may serve as a potential biomarker for asthma control. [ABSTRACT FROM AUTHOR]

Background: Chronic rhinosinusitis with a type 2 inflammatory pattern (T2CRS) is believed to be restricted to the nose and sinuses and associated with polyps, without clear serologic markers. Dupilumab is a promising new therapy in difficult to treat T2CRS. No factors are known to predict dupilumab treatment outcome. Methods: Patients undergoing dupilumab treatment were assessed clinically to report ultra‐short‐ and short‐term outcome up to 90 days. Serum samples were taken on day 0 and 30 days of treatment, and proteomic analyses were performed using Olink®. The results were compared with healthy controls (HC). The aim was to identify clinical and serological markers associated with a treatment response to dupilumab. Confirmation of predictive parameters was evaluated in a prospective cohort of 20 T2CRS patients. Results: Thirty patients were included, 80% of which were treatment responders. SinoNasalOutcomeTest‐20 (SNOT‐20) scores and the total nasal polyp score improved significantly (p <.05) on Day 7. An improvement of 2.5 points at the first visit was associated with a favorable outcome with a sensitivity of 86%. Proteomic analyses revealed significant changes compared with HC. Furthermore, we could identify OPG in the serum of dupilumab‐treated patients that may serve as a predictor of the clinical outcome of dupilumab treatment. The predictive value of OPG was confirmed in the second cohort. Conclusion: Clinical response after 1 week of treatment with dupilumab is highly associated with a favorable outcome. High sensitivity proteomic analyses can identify T2CRS‐specific dysregulated proteins in serum. Serum OPG may serve as a predictor for dupilumab treatment outcome before the initiation of any therapy. [ABSTRACT FROM AUTHOR]

Background: Anaphylaxis is the most acute and life‐threatening manifestation of allergic disorders. Currently, there is a need to improve its medical management and increase the understanding of its molecular mechanisms. This study aimed to quantify the extravasation underlying human anaphylactic reactions and propose new theragnostic approaches. Methods: Molecular determinations were performed in paired serum samples obtained during the acute phase and at baseline from patients presenting with hypersensitivity reactions. These were classified according to their severity as Grades 1, 2 and 3, the two latter being considered anaphylaxis. Tryptase levels were measured by ImmunoCAP, and serum protein concentration was quantified by Bradford assay. Human serum albumin (HSA) and haemoglobin beta subunit (HBB) levels were determined by Western blot and polyacrylamide gel electrophoresis, respectively. Results: A total of 150 patients were included in the study. Of them, 112 had experienced anaphylaxis (83 and 29 with Grade 2 and 3 reactions, respectively). Tryptase diagnostic efficiency substantially improved when considering patients' baseline values (33%–54%) instead of the acute value threshold (21%). Serum protein concentration and HSA significantly decreased in anaphylaxis (p <.0001). HSA levels dropped with the severity of the reaction (6% and 15% for Grade 2 and 3 reactions, respectively). Furthermore, HBB levels increased during the acute phase of all hypersensitivity reactions (p <.0001). Conclusions: For the first time, the extravasation underlying human anaphylaxis has been evaluated based on the severity of the reaction using HSA and protein concentration measurements. Additionally, our findings propose new diagnostic and potential therapeutic approaches for this pathological event. [ABSTRACT FROM AUTHOR]

Background: Atopic dermatitis (AD) is the most common inflammatory skin disease in children, with 30% of all those diagnosed developing chronic or relapsing disease by adolescence. Such disease persistence cannot yet be predicted. The aim of the present study was to predict the natural course of AD using clinical parameters and serum proteins. Methods: Sera of 144 children with AD (age 0‐3 years) were analyzed for IgE and 33 cytokines, chemokines, and growth factors. Patient disease course until the age of 7 years was assessed retrospectively. Unsupervised k‐means clustering was performed to define disease endotypes. Identified factors associated with AD persistence at the age of 7 years were validated in children with AD in an independent cohort (LISA Munich; n = 168). Logistic regression and XGBoosting methods followed by cross‐validation were applied to predict individual disease outcomes. Results: Three distinct endotypes were found in infancy, characterized by a unique inflammatory signature. Factors associated with disease persistence were disease score (SCORAD), involvement of the limbs, flexural lesion distribution at the age of 3 years, allergic comorbidities, and disease exacerbation by the trigger factors stress, pollen exposure, and change in weather. Persistence was predicted with a sensitivity of 81.8% and a specificity of 82.4%. Factors with a high impact on the prediction of persistence were SCORAD at the age of 3 years, trigger factors, and low VEGF serum levels. Conclusion: Atopic dermatitis in infancy comprises three immunological endotypes. Disease persistence can be predicted using serum cytokines and clinical variables. [ABSTRACT FROM AUTHOR]

This study describes a microtiter double antibody assay for the measurement of specific IgG, which is believed to be identical with blocking antibodies. The precipitates were harvested on glass fiber filters, and the activity from iodinated antigens fixed in the precipitates was used as a measure of the level of the serum blocking antibodies. [ABSTRACT FROM AUTHOR]

The article presents abstracts of several research papers published in different journals. One of the abstracts is on quantitative studies describing the in vivo behavior of an inhaled protein antigen. Aerosol mists were generated from bovine serum albumin (BSA) solutions. The fate of inhaled BSA in vivo was studied in rabbits by using a paired-isotope technique to quantitative antigen sequestration within organs. The study suggests that antigen inhalation may function primarily as an important physiologic means by which natural immunity to environmental antigens is established. Another abstract discusses relationship of serum theophylline concentration to inhibition of exercise-induced bronchospasm and comparison with cromolyn. The effect of cromolyn in suppressing exercise-induced bronchospasm was generally much less.

Background: The majority of children with cow's milk allergy (CMA) tolerate baked milk. However, reactivity to fermented milk products such as yogurt/cheese has not been previously evaluated. We sought to determine whether children with CMA could tolerate yogurt/cheese and whether a patient's IgE and IgG4‐binding pattern to milk protein epitopes could distinguish clinical reactivity. Methods: Four groups of reactivity were identified by Oral food challenge: baked milk reactive, fermented milk reactive, whole milk reactive, and outgrown. sIgE and sIgG4 binding to milk protein epitopes were assessed with a novel Luminex‐based peptide assay (LPA). Using machine learning techniques, a model was developed to predict different degrees of CMA. Results: The baked milk reactive patients demonstrated the highest degree of IgE epitope binding, which was followed sequentially by fermented milk reactive, whole milk reactive, and outgrown. Data were randomly divided into two groups with 75% of the data utilized for model development (n = 68) and 25% for testing (n = 21). All 68 children used for training were correctly classified with models using IgE and IgG4 epitopes. The average cross‐validation accuracy was much higher for models using IgE plus IgG4 epitopes by LPA (84.8%), twice the performance of the serum component proteins assayed by UniCAP (41.9%). The performance of the model on "unseen data" was tested using the 21 withheld patients, and the accuracy of IgE was 86% (AUC = 0.89) while of IgE+IgG4 model was 81% (AUC = 0.94). Conclusion: Using a novel high‐throughput LPA, we were able to distinguish the diversity of IgE/IgG4 binding to epitopes in the varying CMA phenotypes. LPA is a promising tool to predict correctly different degrees of CMA. The new food challenge sequence and Luminex‐based peptide assay to identify the clinical phenotypes of reactivity to baked, fermented, and whole cow's milk. [ABSTRACT FROM AUTHOR]

Background: Although chronic urticaria (CU) is often regarded as autoimmune in nature, only less than 50% of sera from CU patients contain histamine-releasing autoantibodies. This suggests that other factors may contribute to its pathogenesis. We evaluated the possible involvement of vascular endothelial growth factor (VEGF), one of the major mediators of vascular permeability, in CU. Methods: Eighty consecutive adult patients with CU and 53 healthy subjects were studied. VEGF and prothrombin fragment F1+2 were measured by enzyme immunoassays. Autologous plasma skin test (APST) was performed in CU patients and, in six of them, skin biopsy specimens were taken from wheals to evaluate the immunohistochemical expression of VEGF and eosinophil cationic protein (ECP). Results: Plasma VEGF concentrations were higher in CU patients (8.00 ± 0.90 pmol/l) than in controls (0.54 ± 0.08 pmol/l) ( P = 0.0001) and tended to parallel both the severity of CU and to correlate with F1+2 levels. APST was positive in 85.1% of patients. VEGF concentration was significantly higher in APST-positive than in APST-negative patients ( P = 0.0003). Immunohistochemically, all specimens from patients with CU showed a strong expression of VEGF ( P = 0.002) that colocalized with ECP, a classic eosinophil marker. Conclusions: VEGF plasma levels are elevated in CU and parallel the disease severity. This supports a possible role of this molecule in CU pathophysiology. Eosinophils are the main cellular source of VEGF in CU lesional skin. [ABSTRACT FROM AUTHOR]

Tissue remodelling reported in upper airways include epithelial hyperplasia, increased matrix deposition in the nasal or paranasal lining, matrix degradation and accumulation of plasma proteins. Genetic influences, foetal exposures and early life events may contribute to structural changes such as subepithelial fibrosis from an early age. Other structural alterations are related to duration of the disease and long-term uncontrolled inflammation. Structural changes may increase alteration of the protective functions of the upper airways namely by affecting mucociliary clearance and conditioning of inspired air. The sequences of tissue changes during wound repair of upper airway mucosa after surgery are illustrative of the complexicity of tissue modelling and remodelling and could be considered as an important source of information for a better understanding of the complex relationship between inflammatory reaction, of the subsequent tissue damages and fibroblast metabolism of upper airways. [ABSTRACT FROM AUTHOR]

The constant regions of the antibodies determine the effector functions of antibodies, such as complement fixation, Fe-receptor binding and traversal of basal membranes. IgE is the least abundant immunoglobulin (Ig) isotype in human serum, but it is the most important isotype mediating allergic reactions. IgE probably evolved because of its protective effect against parasitic infections. It is only IgE that can hind to high-affinity IgE receptors expressed on mast cells and basophils. The cross-linking of these receptors by interaction of the allergen and FeRI-bound IgE leads to degranulation of the mast cells and rapid release of mediator molecules, such as histamine, prostaglandins, and leukotrienes, causing allergic symptoms in the target organs.

IgG antibody response to the inhalant allergen Parietaria judaica (Pj) and IgG subclass distribution were studied in 82 normal subjects, divided into three groups according to age (0-1, 1-20, and 20-60 years) and in 32 allergic subjects aged 20-60 years. Both normal and allergic subjects showed an IgG response, and all had IgG 1 antibodies specific for PjE. Serum IgG2, IgG3, and IgG4 against PjE were detectable in 36%, 46%, and 22% of normal subjects, and in 58%, 31%, and 65% of allergic subjects, respectively. A significant difference in class distribution between allergic and age-matched normal subjects was found only for IgG4 antibodies against PjE (65% and 17%; P < 0.01). The ELISA results were also analyzed quantitatively, taking into account the relative proportion of specific antibodies. Thus, in normal subjects IgG 1 antibodies showed a decreasing trend as the age rose, while no differences according to the age of the subject were found for IgG2 and IgG4. When data from allergic subjects (20-60 years) and the age-matched normal group were compared, they were different for the relative percentage of IgG2 only, showing for this a significantly lower value (P < 0.001). The present data indicate that normal and allergic subjects show differences in the IgG iso type distribution depending on their sensitivity and duration of allergen exposure. [ABSTRACT FROM AUTHOR]

Whereas IgE antibodies are linked with allergy, IgG4 antibodies may reflect the state of immunity and protection against a particular antigen. It has been shown that interleukin (IL)-4 is required for induction of IgE synthesis. In order to elucidate the role of IL-4 in the production of IgG4 and to compare IgG4 and IgE regulatory processes, we quantified these immunoglobulin isotypes after in vitro culture of peripheral blood mononuclear cells (PBMC) in the presence of IL-4. The production of IgG4 was increased by IL-4 under the same conditions which are optimal for IgE production but not among PBMC from all donors, depending on the magnitude of spontaneous IgG4 secretion: IL-4 was effective only when the spontaneous secretion of IgG4 was <7% of the total IgG secretion; it had no effect when spontaneous IgG4 production was >7% of total IgG. The IL-4-induced IgE response was consistently obtained when IgG4 was <7% of total IgG but was markedly diminished or absent when IgG4 was >7% of total IgG. If Staphylococcus aureus strain Cowan 1 (SAC) was present during the 48-h preincubation step, spontaneous IgG4 production was increased, but the stimulatory effect of this mitogen on immunoglobulin production, including IgG4, was markedly blocked by the addition of IL-4. In contrast, IL-4-induced IgE synthesis was strongly blocked by the presence of SAC. Finally, secretion of IgG4 (spontaneous and IL-4-induced) was suppressed among cells from most donors by interferon-γ (IFN-γ). These results suggest that IL-4 has opposite effects on in vitro IgG4 production and that the in vitro synthesis of both IgG4 and IgE appears to be regulated similarly by IL-4 and IFN-γ, whereas additional signals promote the production of one isotype in preference to the other. It is possible that activated B cells respond to IL-4 less well than do nonactivated cells. [ABSTRACT FROM AUTHOR]

A double-blind, placebo-controlled study of immunotherapy was conducted in 19 patients with grass-pollen hay fever to evaluate the efficacy and safety of a formalinized depot grass allergoid. The patients were assessed before and during IT by clinical (symptom-medication scores during the grass- pollen season, specific nasal and skin reactivity) and immunological (specific IgE, IgG, IgG1 and IgG4 antibodies) parameters. High doses of grass allergoid, corresponding to a cumulative pre-seasonal dosage of 46,050 PNU, were administered, with only one systemic reaction. The actively treated patients had significantly lower symptom-medication scores than placebo (p < 0.01) during the month of May and showed a significant decrease in specific skin (p < 0.01) and nasal (p < 0.05) reactivity, and a significant early increase in specific IgE (p < 0.01), IgG (p < 0.0005), IgG1 (p < 0.001) and IgG4 (p < 0.05), with a subsequent decrease of IgE and IgG1. No differences were detected in any of these parameters in the placebo group. A correlation was found between high IgG4/IgG1 ratio and the specific skin reactivity decrease (r = 0.691, p < 0.05), whereas a high IgG4/IgG1 ratio was associated with higher symptom-medication scores (r = 0.654, p < 0.05). Possible explanations of these apparent discrepancies are proposed. [ABSTRACT FROM AUTHOR]

Some parameters which might affect RAST results, i.e. incubation length, degree of ligand substitution, and total IgE levels, were examined in a RAST system employing diphenylmethane diisocyanate--human serum albumin (MDI-HSA) conjugates as antigens, both in exposed symptomatic and in non-exposed subjects. The reaction equilibrium was reached after 9 and 18 h. respectively, in the first and the second step of the test. A marked correlation with the degree of ligand substitution was observed, the highest sensitivity being achieved with the lowest (2.9) MDI/HSA molar ratio examined. Higher (up to 50) degrees of substitution resulted in progressively lower levels of radioactivity bound and in a loss of specificity, as confirmed by RAST inhibition experiments. At high levels of ligand substitution, high titers of total serum IgE affected RAST results. [ABSTRACT FROM AUTHOR]

The development of allergen during metamorphosis of chironomids, Chironomus yoshimatsui and Tokunagayusurika akamusi, was studied by means of ELISA inhibition with pooled serum containing high titer of specific IgE to each adult midge. Extracts of C. yoshimatsui larvae and pupae did not inhibit the specific IgE antibody to adult C. yoshimatsui. Mature adult C. yoshimatsui extract had about 10 times more inhibitory substance than the young adult. Hemoglobin, however, was degraded during the metamorphosis as measured by spectrophotometry and HPLC. The inhibitory substance against specific IgE antibody to adult T. akamusi was identified as highest in female body, less in egg, and even less in wing, leg and male body. The size of the substance in egg and female body was estimated at > 500 kD of molecular weight. [ABSTRACT FROM AUTHOR]

Specific antibodies isolated by immunoabsorption on four main insolubilized allergens from Dermatopkagoides puronyssinus (DPT) had the following isotypic distribution: in 16 atopic patients, 52% IgG, 40% IgM, 8% IgA, 0.1% IgE and, in 12 non-atopic individuals, 48% IgG, 46% IgM, 6% IgA, 0.03% IgE. The ratios between geometric means of antibody values in each class (atopic vs non-atopics) were 2.4 for IgG, 2,0 for IgM, 2.8 for IgA and 66.7 for IgE. The amount of anti-DPT antibodies in IgG subclasses did not follow the usual distribution cf total IgG subdasses, i.e., IgGl > IgG2 > IgG3 > IgG4. In atopies the order was IgG2 > IgGl > IgG4 > IgG3 and in non-atopies, IgG4 > IgGl = IgG2 > IgG3 although 6/12 of the latter had no detectable (< 0.5 μg/ml plasma) IgG4. [ABSTRACT FROM AUTHOR]

IgG-binding to the surface of Langerhans cells (LC) is a feature of primary Sjogren's syndrome and might be associated with qualitative and quantitative defects in LC. Fifteen patients with primary' Sjogren's syndrome and 15 healthy controls had a punch biopsy performed from clinically unaffected skin. LC were enumerated in epidermal sheets by an immunoperoxidase technique, as well as demonstrated by immunofluorescence in vertical sections, which were furthermore examined for in vivo deposits of immunoglobulins, fibrinogen and C3. A significant (P < 0.05) reduction in number of LC, measured on epidermal sheets, was found in patients as compared with controls. Examination of vertical sections did not reveal abnormalities in morphology or localisation of epidermal LC. Intraepidermal IgG deposits were demonstrated in 7/15 patients. In vivo deposits were not found in any of the controls, The density of epidermal LC was not correlated to the presence of intraepidermal IgG deposits. [ABSTRACT FROM AUTHOR]

A crossed radioimmunoelectrophoresis (CRIE) method for detection of specific IgG antibodies in patients" sera against horse hair and dander was developed. The unacceptably high non-specific binding encountered when substituting 125l-labelled antihuman IgG for 125l-labelled antihuman IgE in an ordinary CRIE was estimated by the combined use of 125l-labelled Protein A as detector, and F(ab)2-fragments of the allergen-specific rabbit antibodies. The low background binding thus obtained makes the method useful for detection of specific IgG in sera where the ratio between specific and non-specific IgG is low. Therefore the method should also be applicable to other antigen/allergen symptoms. [ABSTRACT FROM AUTHOR]

A further study has been made on the house dust mite extract, Dermatophagoides pteronyssinus, with emphasis on gel-filtrated fraction 2 (F2). The crude mite extract showed at least nine discs on polyacrylamide disc electrophoresis and contained less than 0.25% sialic acid and less than 0.5 mM hexosamine and no detectable uronic acid. From gel filtration of the crude extract a No 2 fraction (F2) with allergenic activity showed at least five components on SDS disc electrophoresis covering a molecular weight range of between 15,000 and 70,000. The major allergenic activity of F2 dissolved in pH 7-8 and 4-5 on an isoelectric focusing column. Affinity chromatography and lectins showed that allergenic activity did not relate to structures of N-acetyl-D-glucosamine or N-acetyl-D-galactosamine. Allergenic activity of the crude extract was no affected by peptic digestion and the mite digest prepared by trypsin and pronase showed a similar fractionation and activity profile as crude extract. [ABSTRACT FROM AUTHOR]

Bee venom obtained by electrical stimulation has been analysed by crossed immunoelectrophoresis against high-titer rabbit antibodies. The antigenic analysis of bee venom revealed that the extract contained 17 antigens, which were detected in the crossed immunoelectrophoresis pattern after staining with Coomassie Brilliant Blue. The crossed immunoelectrophoresis pattern indicated heterogeneity in several of the antigens, as most of the precipitates (exhibiting enzyme and hemolytic activities) represented multiple forms of phospholipase A, hyaluronidase, acid phosphatase and melittin. [ABSTRACT FROM AUTHOR]

The nature and extent of bacterially induced allergies are difficult to define. Since peptidoglycan, the main component of the cell wall of almost all bacteria, has been available in a highly purified, chemically and immunologically well-defined form, investigation of the allergological significance of this cell component is feasible. Intracutaneous tests were carried out on 181 test subjects with five different peptidoglycan (PG) preparations from Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus Pyogenes. The results of the investigation were compared with the result of determination of serum PG antibodies and serum IgE concentrations. It was shown that test subjects with dual and later reactions to three different staphylococcal PGs displayed significantly higher PG antibody titers than test subjects with negative reactions. Such a relationship could not be found with the cutaneous reactions to streptococcal PG. The total serum IgE values were very much higher in test subjects with immediate reactions to staphylococcal PG than in test subjects with a negative reaction. Typical Arthus reaction or late granulomatous reactions were not observed. Humoral antibodies are involved at least in part in the elicitation of dual and late reactions. Thus, there are interesting parallels to allergy to fungal spores and organic dusts. [ABSTRACT FROM AUTHOR]

Bacterial respiratory infections, especially with Haemophilus influenzae and Streptococcus pneumoniae, are frequently associated with an increase of airways obstruction in patients with bronchial asthma. The possible involvement of immediate hypersensitivity in this phenomenon was studied. IgE antibodies to Haemophilus influenzae (HI) and Streptococcus pheumoniae (SPn) were investigated in the serum of 190 adult patients with bronchial asthma. The IgE antibodies were measured using a solid phase radioimmunoassay method. Living bacteria were used as solid phase. A correction of the non-specific binding of IgE was necessary. IgE antibodies to one or both bacteria were present in 55 of the 190 patients (29%). Eighteen patients were sensitive to HI, 33 to SPn and four to both bacteria. Significantly more IgE antibodies to bacteria were found in patients with demonstrable IgE antibodies to various inhalant allergens. However, the IgE antibodies to one or both bacteria were also present in 22% of patients with no other demonstrable IgE mediated hypersensitivity. The total serum IgE level in patients with IgE antibodies to bacteria was not significantly higher than in patients without hypersensitivity to these bacteria. From these data we concluded that immediate hypersensitivity to bacteria may play a role in the infectious exacerbations of bronchial asthma. [ABSTRACT FROM AUTHOR]

Sera from 425 patients were analysed with Phadebas RAST reagents against a panel of 19 allergens and the most commonly positive results were to grass pollen, Dermatophgoides pteronyssinus and cat epithelium. Of the 275 sera RAST-positive to any allergen, 261 were positive by a RAST technique which used a mixture of the three most common U.K. allergens; the remainder were usually positive to a mould. We conclude that 1) when a positive result is obtained after screening by the mixed-allergen RAST and a representative mould RAST, then other positive RAST results are possible, but that the extent of the investigation can be guided by a knowledge of the total serum IgE level and a computer-based history analysis; 2) when the mixed-allergen RAST and a representative mould RAST is negative, then a more specified RAST including all 19 allergens used in this investigation will be negative; 3) a positive mixed-allergen RAST result is likely to be associated with a total serum IgE level over 40 U/ml and a positive symptom pattern score derived from the computer-based history analysis. [ABSTRACT FROM AUTHOR]

Since one of the greatest reservoirs of allergens is the blanket, we assessed mite allergen levels in dust collected from five blankets by vacuuming before and after dry cleaning with perchlorethylene and compared the results with five control blankets. Assays with monoclonal antibodies showed that group I (Der p I and Der f I) mite allergen levels per g dust were 78% lower after dry cleaning. Group I allergen levels per m² of dry-cleaned blankets were 98% Lower. RAST inhibition showed that total allergen levels decreased 70% after dry cleaning. Mite allergens were not denatured by perchlorethylene. The effect of dry cleaning resulted from physical washing out of dust and allergens. [ABSTRACT FROM AUTHOR]

The article presents information on the sources of allergens in animals. In furred animals, fur and dander is commonly regarded as the natural source of allergenic material. Cat serum albumin and another serum-derived protein have been demonstrated to be minor cat allergens, these proteins are also presents in pelt and saliva; albumin is also present in urine. Dog urine has a considerably weaker allergenic activity per total protein amount than saliva or dander, but urinary allergens are claimed to be more dog-specified than dog dander, probably because urine may contain less serum-derived proteins, which have been shown to cross-react with cat allergens.