Passive sensitization of human airways induces myogenic contractile responses in vitro

We assessed effects of passive sensitization on human bronchial smooth muscle (BSM) response to mechanical stretching in vitro. Bronchial rings were sham (control) or passively sensitized overnight by using sera from donors demonstrating sensitivity to Dermatophagoides farinae and having immunoglobulin E (IgE) concentrations of 2,600 +/- 200 U/ml. Tissues were fixed isometrically to force transducers to measure responses to electrical field stimulation (EFS) and quick stretch (QS). The myogenic response to QS was normalized to the maximal response to EFS (%EFS). The myogenic response of sensitized BSM was 47.9 +/- 10.9 %EFS to a QS of approximately 6.5% optimal length (Lo); sham-sensitized tissues had a myogenic response of 13.5 +/- 6.4 %EFS (P = 0.012 vs. passively sensitized). A QS of approximately 13% Lo in sensitized BSM caused a response of 82.8 +/- 20.9 %EFS; sham-sensitized tissues developed a response of 38.2 +/- 17.3 %EFS (P = 0.004). BSM incubated with serum from nonallergic donors did not demonstrate increased QS response (4.6 +/- 1.4 %EFS, P = not significant vs. tissue exposed to atopic sera). However, tissues incubated in sera from nonatopic donors supplemented with hapten-specific chimeric IgE (JW8) demonstrated augmented myogenic response to QS of approximately 6.5% Lo (21.9 +/- 6.2 %EFS, P = 0. 027 vs. nonatopic sera alone). We demonstrate that passive sensitization of human BSM preparations causes induction and augmentation of myogenic contractions to QS; this hyperresponsiveness corresponds to the IgE concentration in sensitizing sera.     

Factors influencing immediate responses to intradermal allergen administration in patients with respiratory allergy

BACKGROUND: Immediate skin reactions to allergens are influenced by several factors, such as the amount of administered allergen, the level of specific IgE, releasability of mast cells and hyperresponsiveness of the target organ. METHODS: For the evaluation of factors influencing immediate skin response to intradermal allergen administration, we measured the wheal size 15 min after intradermal injection of 0.01-0.02 ml of the following agents: whole-body extract of Dermatophagoides farinae, 1,000 allergy units/ml; histamine, 0.1 mg/ml, and codeine sulfate, 0.09% in saline, and determined total IgE level, specific IgE and IgG subclass antibodies to D. farinae in 53 patients with respiratory allergy. RESULTS: Multiple regression analysis for factors influencing wheal size after intradermal injection of D. farinae, specific IgE antibody level to D. farinae and wheal size after intradermal administration of histamine showed statistically significant results (R2 = 0.42739, p = 0.0000; R2 = 0.50243, p = 0.0185, respectively). Multiple regression analysis for factors influencing wheal size after intradermal administration in the group with high levels of specific IgE to D. farinae (RAST class 3 or more) showed that wheal size after intradermal administration of codeine was the only factor exerting a statistically significant influence (p = 0.0119). CONCLUSION: Based on the above results, we can state that immediate responses to intradermal allergen administration were influenced by the level of specific IgE and hyperresponsiveness of the target organ to histamine, but that the immediate skin allergic responses in the presence of high levels of specific IgE were partially but significantly influenced by the releasability of skin mast cells.     

IgE-induced passive sensitization of human isolated bronchi and lung mast cells

Passive sensitization of human isolated lung with serum from atopic asthmatic patients provides an opportunity to study the link between airway hyper-responsiveness and the allergic process. To directly demonstrate the role of immunoglobulin E (IgE) in the effect of the atopic serum, we have compared the effect of passively sensitizing both human bronchi and isolated lung mast cells with either serum from atopic asthmatic patients or human monoclonal IgE. Peripheral bronchi ( < 5 mm in internal diameter) were dissected out from human lung obtained at thoractomy and isometric contraction was studied in response to a variety of immunological stimuli according to the sensitization protocol. Mast cells were also isolated from human lung and histamine release was measured under similar experimental conditions. A contractile response was elicited by either the specific antigen or anti-IgE (0.6-600 ng.mL-1) but not anti-immunoglobulin G (IgG) 0.2-20 micrograms.mL-1) in airways sensitized with atopic serum (total IgE concentration of approximately 1,000 international units (IU).mL-1). The maximal contractile response to anti-IgE was 75 +/- 22% of the response to 1 mM acetylcholine. Similarly, anti-IgE released histamine from isolated lung mast cells sensitized with atopic serum up to 22.4 +/- 2% of total histamine measured within mast cells. When isolated airways or mast cells were sensitized with human monoclonal IgE (1,000 IU.mL-1), response to anti-IgE in terms of contractile response or histamine release, respectively, were not significantly different from those obtained following passive sensitization with atopic serum. Finally, the bronchial contractile response to anti-IgE depended not only on the concentration of anti-IgE but also on that of IgE (300-2,000 IU.mL-1) used to sensitize the airways. These results indicate that the effect of antigen or anti-IgE in peripheral bronchi passively sensitized with atopic serum is mimicked when sensitization is carried out directly with human monoclonal IgE.     

The mite allergen and allergoid stimulation of histamine secretion by mast cells

Rat peritoneal mast cells were incubated with serum from highly mite-sensitive patients. It was demonstrated that exposure of passive sensitized mast cells to allergen from mites Dermatophagoides farinae induced the release of histamine. Exposure of mast cells to 10 micrograms/ml and 50 micrograms/ml mite allergen resulted in an increase of histamine secretion to 48% of the basal level. The allergoid (formaldehyde-modified mite allergen) had poor histamine-releasing activity compared to allergen. The allergoid (50 micrograms/ml) induced a 2.5-fold decrease in histamine release. The allergen at the same concentrations and the same release as allergen in dose 0.1 microgram/ml.     

Sunlight and sunburn in human skin cancer: p53, apoptosis, and tumor promotion

Levels of allergen-specific IgE and IgE antibodies were determined in serum samples from 60 atopic and 11 normal dogs by means of commercially available ELISA test kits and a panel of 33 allergens. In the atopic population, IgE antibodies were most commonly identified with a specificity for Dermatophagoides farinae (78.3 per cent of affected dogs), D pteronyssinus (61.6 per cent), mould mix (25 per cent) and house dust (19 per cent), whereas the most frequently detected IgG antibodies had a specificity for D farinae (38.3 per cent), D pteronyssinus (33.3 per cent), mould mix (33.3 per cent), insect mix (16.6 per cent) and meadow fescue (16.6 per cent). The IgG subclass profile of allergen-specific antibodies was determined for five representative allergens from the panel. The IgG response to D farinae and D pteronyssinus was dominated by IgG4 antibodies, although lower levels of IgG2, and IgG3 and IgG1 D pteronyssinus antibodies were also detected. The IgG response to Timothy grass was predominantly within the IgG1 and IgG4 subclasses, IgG subclass selection in the response to mould mix and insect mix was broader, with relatively low level reactions from all four subclasses. The data suggest a degree of IgG subclass restriction in the humoral immune response of canine atopy which may be dependent upon the nature of the allergen.     

A clinical evaluation in children of the Pharmacia ImmunoCAP system for inhalant allergens

BACKGROUND: The Pharmacia ImmunoCAP system (CAP) for assaying serum IgE specific antibodies was evaluated in a clinical setting against skin-prick test (SPT) performed using Dome/Hollister-Steir allergen extracts. The five common inhalant allergens D. pteronyssinus, D. farinae, mould mix, grass mix and cat epithelium were tested concurrently by both methods in 167 children aged 7.5-12 years. The specific SPT for D. pteronyssinus and D. farinae were also tested against the CAP house dust mite (HDM) mix. OBJECTIVE: The purpose of the study was to determine the sensitivity and specificity of the Pharmacia ImmunoCAP system for detecting serum IgE specific antibodies to inhalant allergens in a clinical setting, using SPT result as the "gold standard'. METHODS: The SPTs were performed using Dome/Hollister-Steir allergen extracts. The serum IgE specific antibodies were quantitated using the radioimmunoassay version of the Pharmacia ImmunoCAP system. A history of allergic disease was assessed using a validated questionnaire. RESULTS: SPT gave more positive reactions than CAP with the exception of cat epithelium. The concordance between SPT and CAP results was 91% over all the tests. The concordance with SPT was slightly higher for the specific CAP for D. pteronyssinus and D. farinae (93% and 95% respectively) than for the CAP HDM mix (86% and 90% respectively). There was a higher proportion of positive results for both SPT and CAP in the 115 children defined as having a history of allergic disease. Using SPT defined allergy as the gold standard, the sensitivity of the CAP system was 87% for the two specific house dust mites but was lower for cat epithelium (67%), mould mix (59%) and grass mix (46%). The sensitivity of the CAP system improved for D. pteronyssinus (96%) and the HDM mix (91%) when tested in subjects defined as having a history of allergy associated disease. The specificity of the CAP system showed less variation between allergens and ranged from 90-99%. CONCLUSION: The results of this study of children aged 7.5-12 years demonstrate that, for the inhalant allergens tested, the Pharmacia ImmunoCAP system performs well in the setting of known allergic disease.     

Identification of peptide fragments chemically cross-linked in cytochrome c oxidase from thermophilic Bacillus PS3

It has been suggested that differential histamine-releasing activity of an IgE-dependent histamine-releasing factor (HRF), which has recently been cloned, is related to carbohydrate difference in the IgE molecule. Lectins are able to recognize specific glycoforms and might therefore be useful in characterizing the proposed heterogeneity of IgE molecules. As one test of this hypothesis, we examined the histamine release potency of several well-characterized lectins on basophils passively sensitized with serum containing IgE molecules that support HRF-induced histamine release (IgE+) or serum that does not support release by this stimulus (IgE-). Histamine release was induced by challenging basophils with different concentrations of concanavalin A, Lens culinaris (LcH), and Pisum sativum (PSA). Dose-response curves revealed that LcH caused 30% histamine release at 2 micrograms/ml with IgE+ sensitized cells, whereas the same release with IgE- cells required sixfold higher concentrations. Similar values for PSA showed a sevenfold difference. With concanavalin A, the selectivity was reversed in that it was fourfold more active on IgE- -sensitized cells. Another pair of sera (IgE+ vs IgE-) revealed the same result for concanavalin A, but no difference occurred in LcH and PSA induced release between the IgE+ - and IgE- -sensitized cells. These contrasting findings with different pairs of IgE+ -and IgE- -containing sera indicated that the lectins LcH and PSA are not able to discriminate between IgE+ -and IgE- -sensitized cells as does HRF and therefore cannot be used to further define the proposed heterogeneity of IgE. this conclusion was supported by experiments in which basophil preparations from donors possessing natural sensitivity or insensitivity to HRF (having IgE+ or IgE- on their surface) were examined fro their response to these lectins. No difference was found in the sensitivity of the cells to challenge with LcH or PSA, and the response to concanavalin A was the opposite of that found when passively sensitized cells were used (30% histamine release at 0.9 vs 3.5 micrograms/ml for IgE+ vs IgE- donors, respectively). We conclude that oligosaccharide-specific lectins do not differentiate between HRF-reactive and HRF-nonreactive IgE molecules on basophils.     

Allergen challenge of passively sensitized human bronchi alters M2 and beta2 receptor function

We investigated whether antigen challenge may alter M2 and beta2 receptor function in isolated passively sensitized human bronchi. Bronchial rings (2-4 mm internal diameter) were obtained from 12 patients. Passive sensitization was induced by serum containing high IgE levels to Dermatophagoides pteronyssinus and Dermatophagoides farinae. Rings from six patients were used to study M2 receptor function by incubating with cumulatively increasing concentrations (10(-8) M to 10(-4) M) of pilocarpine and applying electric field stimulation (EFS) at 24 Hz. The rings from the other six patients were used to study beta2 receptor function by precontracting with carbachol 10(-6) M and adding cumulatively salbutamol (10(-9) M to 10(-4) M). Additional rings from these patients were used to determine whether dysfunction occurred distal to cAMP production by precontracting with carbachol 10(-6) M and adding cumulatively theophylline (10(-9) M to 10(-4) M). The attenuation of EFS-induced force by pilocarpine and the relaxation of carbachol-precontracted rings by salbutamol were less in challenged than in control and sensitized rings. No difference between challenged, sensitized, and control rings was observed with theophylline. We conclude that allergen challenge in passively sensitized isolated human bronchial rings may result in M2 and beta2 receptor dysfunction without involving mechanisms distal to cAMP formation. It appears that products from inflammatory cells recruited from blood are not necessary for this receptor dysfunction.     

In vitro passive sensitization of the ureter as a basis for the study of noninfectious ureteral inflammation

PURPOSE: To develop an in vitro model of passive sensitization for the ureter for the study of noninfectious ureteral inflammation. MATERIALS AND METHODS: Human ureteral tissues were obtained from excess segments of ureters from patients undergoing donor nephrectomy. Following excision, ureters were placed in physiologic salt solution (PSS) and passively sensitized by incubating with ragweed serum from allergic donor (1 ml. serum: 4 ml. PSS) for 20 hours at room temperature. Ureteral segments were incubated with PSS only and served as non-sensitized controls (n = 4). After sensitization, excess serum was removed by serial washing with PSS without serum. Ureteral strips were then suspended in vitro for determination of tissue contraction. Contractile responses and histamine release were measured. Tissues were then exposed to antigen. To investigate the role of inflammatory mediators in tissue contraction, 4 groups of 8 sensitized ureteral segments were incubated for 1 hour with the following substances: a H1 histamine receptor antagonist (pyrilamine), an inhibitor of prostaglandin synthesis (indomethacin), an inhibitor of leukotriene synthesis (A-64077), and a control substance (DMSO). Following incubation, the tissues were exposed to antigen, and contraction and histamine release were determined. RESULTS: Sensitized ureteral segments (n = 8) responded to antigen with contraction (30% BaCl maximum; p <0.01) and histamine release (205/ng./gm. tissue) within the first 5 minutes of superfusion. Non-sensitized control segments (n = 4) did not respond. Both indomethacin and pyrilamine reduced (7-10% of BaCl maximum; p <0.05) the contractile response of sensitized ureter to antigen, whereas A-64077 did not. Analysis of the superfusate for histamine indicates that indomethacin reduced histamine release (150 ng./gm.) whereas A-64077 and pyrilamine did not (p <0.05). CONCLUSION: We have demonstrated that ureteral segments can be passively sensitized and that subsequent antigen challenge stimulates contraction and histamine release. Our findings suggest that contraction of ureteral tissue and histamine release may be utilized as an inherent bioassay indicating the activity of inflammatory mediators. In addition, these results suggest that both prostaglandins and histamine, but apparently not leukotrienes, participate in the early inflammatory response to antigen challenge of the sensitized ureter.     

Prevalence of malingering in inpatient suicide ideators and attempters

OBJECTIVE AND DESIGN: In an attempt to study the pathogenesis of mucosal hypersensitivity in allergic rhinitis, we investigated the suppressive effects of cyclosporin A (CyA) and glucocorticosteroids on ovalbumin (OA)-induced hypersensitivity to topical histamine challenge. MATERIALS: Actively sensitized Dunkin-Hartley guinea pigs. TREATMENT: OA and alum were applied to guinea pigs intraperitoneally 3 times at two-week intervals. After general sensitization, OA inhalation was performed every day for 6 days as topical sensitization. Before inhalation, treatment with CyA (50 mg/kg, p.o.), glucocorticosteroids (beclomethasone propionate (1.0 mg/kg, i.p.), fluticasone propionate (FP, 0.5 mg/kg, i.p.)) or vehicle were performed, and the sensitivity to histamine was measured before and after the inhalation. Moreover, in actively (general and topical) sensitized guinea pigs, FP (0.5 mg/kg, i.p.) was applied every day for 5 days and histamine sensitivity was evaluated before and after the application. RESULTS: We found that histamine sensitivity was significantly increased by nasal antigen challenge in this guinea pig model, and that the occurrence of histamine hypersensitivity was inhibited by the pretreatment with CyA and glucocorticosteroids. Although multiple administration of FP gradually reduced the histamine hypersensitivity according to the period of administration, it did not significantly alter the histamine hypersensitivity after the occurrence of hypersensitivity. CONCLUSION: It is concluded that CyA and glucocorticosteroids suppress antigen-induced histamine hypersensitivity in a guinea pig model of allergic rhinitis.     

Vernal keratoconjunctivitis in the child. Clinical and complementary study apropos of 22 cases

PURPOSE: Vernal kératoconjunctivitis was studied in a population of 22 children aged 3 to 14 years and followed up in an allergy and ophthalmology outpatient clinic. The role of allergy and the severity of inflammation where assessed by a systematic exploration, which combined a detailed allergy evaluation and blood and lacrimal sampling. MATERIALS AND METHODS: Allergy criteria chosen and recorded in 9 cases are: an increase of total IgE over the higher limit for the age, a positive skin prick test to one allergen, a positive serum specific IgE dosage (> 0.35 IU/mL) of specific IgE. Conjunctival allergy was present in 6 of the 9 children with a positive allergenic provocation test, or with a high local production of total IgE and a lacrimal/serum eosinophilic cationic protein ratio greater than one. RESULTS: Criteria used for supporting the IgE mediated hypersensitivity diagnosis are discussed: they have to be very strict to eliminate false positive results. Allergen involvement can only be evidenced by a specific provocation test. When evidenced as described, limbic or palpebral conjunctivitis had the same frequency. Lacrimal ICAM 1 levels seemed to be higher (p < 0.05) in the severe limbal forms (24.7 +/- 3 pg/mL) than in the palpebral ones (8.1 +/- 6.5 pg/mL). Interpretation of biological parameters evidencing conjunctival inflammation is more difficult. CONCLUSION: Allergic involvement in child vernal keratoconjunctivitis can only be assessed through a detailed evaluation, leading to a specialised ophthalmic and allergic management. A specific treatment can then be established, based on allergen eviction and possibly on specific immunotherapy (5 cases). H1 antihistamin treatments are dedicated only to children with a positive allergic evaluation.     

Effect of cetirizine on antigen-induced tracheal contraction of passively sensitized guinea pigs

BACKGROUND: Cetirizine dihydrochloride (cetirizine), a potent histamine H1-receptor antagonist, has been developed as an anti-allergy drug. OBJECT: The anti-allergic effects and mechanism of cetirizine were studied using in vitro assay systems. METHODS: We investigated the effect of cetirizine on antigen-induced contractions of isolated tracheal strips and on chemical mediator release from antigen-stimulated lung chips taken from passively sensitized guinea pigs. We examined the antigen-induced mobilization of Ca2+ in MC/9 mast cells sensitized with IgE. RESULTS: Cetirizine inhibited the antigen-induced contraction of isolated guinea-pig trachea concentration dependently. Pyrilamine, another histamine H1-receptor antagonist, delayed the response but did not change the maximum amplitude. Cetirizine at the concentration of 3 microM also inhibited the antigen-induced release of histamine, leukotriene D4, and leukotriene E4 from guinea pig lung chips. Furthermore, it inhibited the antigen-induced Ca2+ increase in MC/9 mast cells, whereas pyrilamine did not. CONCLUSION: These findings suggest that one anti-allergic mechanism of cetirizine may inhibit mediator release which is, at least partially, mediated by a decrease in the transient Ca2+ influx in mast cells.     

Norepinephrine accelerates HIV replication via protein kinase A-dependent effects on cytokine production

In vivo, IgE production is related to bronchial hyperresponsiveness and, in vitro, passive sensitization of human airways with asthmatic serum containing a high concentration of IgE enhances the contractile response to a variety of agonists. However, cell types implicated in this IgE sensitization are not fully determined. The aim of this study was to determine IgE-bearing cells during passive sensitization with special reference to mast cells. Peripheral bronchi were dissected out from 10 lung specimens obtained at thoracotomy and processed into glycolmethacrylate resin. Sections, each 2 microm thick, were passively sensitized by incubation for 2 h at 37 degrees C in either buffer supplemented with monoclonal IgE or asthmatic serum with a high concentration of IgE (> or = 1,000 IU/ml). Immunohistochemistry was performed using monoclonal antibodies directed against the epsilon chain, and markers of the various IgE-bearing cells (e.g., AA1, antichymase). The number of IgE-bearing cells was significantly higher in passively sensitized specimens as compared with nonsensitized specimens (6.63 +/- 1.71 versus 4.29 +/- 1.35/mm2; p = 0.013, n = 10). Mast cells represented 65% of IgE-bearing cells, 41.6 and 23.4% for TC and T subtypes, respectively. These results indicate that mast cell is the main cell type involved in IgE-induced passive sensitization. The involvement of mast cell-derived tryptase in the mechanisms of IgE-related hyperresponsiveness should be further examined.     

SEK1/MKK4 is required for maintenance of a normal peripheral lymphoid compartment but not for lymphocyte development

BACKGROUND: Bronchial asthma is characterized by a TH2 type immune response, chronic inflammation of the airways and increased airway responsiveness. The relationship between IgE- and inflammatory-dependent mechanisms that contribute to bronchial asthma are not well defined. OBJECTIVE: The purpose of this study was to compare and analyse the immune pathways that resulted in development of allergen-induced and/or inflammatory dependent increased airways responsiveness. RESULTS: BALB/c and C57BL/6 mice responded to OVA-sensitization with elevated allergen-specific IgE/IgG1 serum antibody-titres and the development of cutaneous immediate-type hypersensitivity reactions. Increased airway responsiveness was observed following airway allergen challenges. However, the inflammatory component of the lung differed between the strains. In OVA-sensitized BALB/c mice a marked increase in lymphocytes, eosinophils and neutrophils in BAL fluids was parallelled with elevated production of IL-4, IL-5 and TNFalpha in the lung. In contrast in OVA-sensitized C57BL/6 mice, the inflammatory immune response in the lung was much weaker. We postulate that two pathways can regulate the induction of increased airway responsiveness. One depends on the presence of allergen-specific IgE/IgG1 and allergen, and a second is mediated by allergen-independent inflammation of the lung. To test this hypothesis, BALB/c mice were treated nasally with low doses of bacterial superantigen (SEB) as a prototypical inducer of airway inflammation, following which influx of lymphocytes, eosinophils and neutrophils into the airways was parallelled by development of increased airway-responsiveness in the absence of allergen-specific IgE/IgG1 antibodies and allergen. CONCLUSIONS: These results indicate that increased airway responsiveness is associated with different immunological phenotypes in BALB/c and C57BL/6 mice.     

L-deprenyl as an adjunct to low-dose bromocriptine in early Parkinson''s disease: a short-term, double-blind, and prospective follow-up study

The potential role of allergen-specific IgG antibodies as 'blocking' antibodies in allergen-induced human basophil histamine release was investigated. This was studied in a model with the major grass pollen allergen Lol p I and polyclonal rabbit antisera directed against this allergen and against a synthetic peptide of its C terminus. When allergen and antibodies were allowed to preincubate, Lol p I induced histamine release was inhibited up to 85% by the antiserum against Lol p I. By omitting preincubation, and thereby more closely mimicking an in vivo situation, up to 55% inhibition was realized. This indicates that allergen-specific IgG can act as 'blocking' antibody without preincubation. Immunization of rabbits with a synthetic C-terminal peptide of Lol p I resulted in antibodies reactive with natural Lol p I. Despite their 100-fold lower avidity for Lol p I (as compared with antinatural Lol p I), these antibodies had the capacity to inhibit Lol p I induced histamine release for > 90% (up to 50% without preincubation). This indicates that it is possible to block histamine release induced by a major allergen with low-avidity IgG antibodies directed against a minor proportion of the allergen (25 amino acids). IgE antibodies from the donors studied were unreactive with this synthetic peptide, indicating that for blocking activity identical epitope specificity of IgE and IgG is not essential. This opens interesting perspectives for application of synthetic peptides in immunotherapy, distinct from their effects on T cell reactivity.     

The house-dust mite and childhood asthma in the Cape Peninsula

Sensitivity to house-dust and the mites Dermatophagoides pteronyssinus and D. farinae was the commonest cause of asthma in children living in the Cape Peninsula. Of 103 asthmatic children examined, 65,5% had positive skin tests to these allergens. Only a small number of the children were sensitive to pollens, feathers, moulds or food. The median serum IgE level was 496 U/ml, with a range of 18-15972 U/ml, and the median blood eosinophil count was 691/microliter (range 93-8 159) in 102 of the children.     

Expression of protein kinase C gene family members is temporally and spatially regulated during neural development in vitro

The dog mastocytoma BR cell line provides us with a permanent source of canine mast cells, allowing a characterization of secretory mediators that exert important effects in canine allergic and nonallergic diseases and in physiological processes. We studied the ultrastructural characteristics and histamine releasing activity after immunological and non-immunological stimuli of the dog mastocytoma BR cell line, and compared the cell line to normal skin mast cells enzymatically isolated from healthy dogs. The histamine content of BR cells was 0.04 +/- 0.002 pg/cell, approximately 100-fold less than that found in canine skin mast cells. Non-immunologic stimuli induced similar concentration-dependent histamine release from skin mast cells and BR cells: 29.3 +/- 0.9% vs. 12.7 +/- 0.7% (calcium ionophore A23187), 23.3 +/- 0.7% vs. 18.8 +/- 0.7% (substance P) and 12.5 +/- 0.3% vs. 12.1 +/- 0.9% (compound 48/80), respectively. Immunologic stimulation, however, was only effective on canine skin mast cells, causing 30.9 +/- 1.7%, 27.7 +/- 0.6% and 12.2 +/- 0.9% histamine release in response to anti-canine IgE, concanavalin A, and antigen Asc S 1, respectively. The absence of functional IgE receptors in BR cells was confirmed by the lack of response to anti-IgE and antigen Asc S 1 following passive sensitization with dog atopic serum and dog antigen sensitized serum. We conclude that BR cells are able to release histamine after non-immunologic stimulation in a similar manner to canine skin mast cells, but that there are morphological and functional differences possibly due to different states of maturity or differentiation. For this reason the study of the highly homogeneous BR cells could offer insights into dog mast cell biology in contexts where freshly isolated cells cannot be used because of low purity and recovery.     

Diagnosis and rehabilitation strategies for patients with hysterical hemiparesis: a report of four cases

BACKGROUND: Sulphidoleukotrienes (slt) are important mediators in allergic diseases that are synthesized after allergen-specific stimulation. OBJECTIVES: The aim of this study is to determine in vitro slt production after allergen-specific (Dermatophagoides pteronyssinus) stimulus of peripheral blood leucocytes and to observe whether histamine release in whole blood with the same allergen correlates with slt production. We also wanted to evaluate whether a correlation exists between the release of slt and histamine and other diagnostic procedures as well as various clinical situations. METHODS: We studied 62 patients sensitive to Dermatophagoides pteronyssinus (Der p), 30 atopic controls and 12 healthy donors. We determined slt production using the CAST-ELISA technique and histamine release using two concentrations of Der p extract (20 and 2 ng/mL). We also carried out quantification of specific and total IgE levels, skin tests and pulmonary function test on each patient. RESULTS: We observed a significantly increased slt release after in vitro stimulation with Der p. There was a significant difference in the slt release between controls and sensitive patients (P < 0.001) and between atopic controls and sensitive patients (P < 0.001). The data are similar to those obtained with histamine release. We noted a positive correlation (P < 0.001) between slt and histamine release (r = 0.71, at 2 ng/mL and r = 0.83 at 20 ng/mL). We also found a positive (P<0.001), although weak (r=0.4 with at 2ng/mL, and r = 0.34 with P = 0.003 at 20 ng/mL) correlation between slt release and specific IgE levels as well as between slt release and skin-test reactivity (r = 0.49 at 2 ng/mL and r = 0.45 at 20 ng/mL; P < 0.001). No significant correlation between slt release and asthma severity was observed, although a trend toward higher slt production in severe and moderate asthma was detected. We found a significant (P<0.001) but weak (r=-0.3) negative correlation between age and slt release. With respect to sex-related differences, we found significant differences (P < 0.05) in slt release between the sexes with a higher slt release in men than in women. CONCLUSION: We conclude that CAST-ELISA for quantification of slt production is a useful in vitro method for diagnosing sensitization to Der p. There also exists a close correlation between slt release and other parameters of allergic sensitization in vitro as well as in vivo.     

Allergen-specific IgE and IgGd antibodies in atopic and normal dogs

Intradermal skin tests (IDSTs) were performed on 65 atopic and 24 normal dogs. The levels of allergen-specific IgE and IgGd antibodies were determined in serum samples by enzyme-linked immunosorbent assay (ELISA) using the same 12 allergens that were used in the IDST on normal dogs. The correlation between the levels of IgE and IgGd to Dermatophagoides farinae (DF) and Dermatophagoides pteronyssinus (DP) was examined. The sensitivity, specificity and positive and negative predictive values of allergen-specific IgE and IgGd levels in the total dog population were also compared. Results were consistent and reproducible for 9/12 allergens, but in the case of house dust, flea and Alternaria tenuis, a less discriminating standard curve and the fact that the negative control gave positive results, suggests non-specific binding and that these allergens are complex and should not be employed without further purification. A high percentage of atopic dogs had positive IDSTs and detectable IgE and IgGd antibodies to DF, DP and house dust. Similar results were obtained in the normal dog population. There were significant correlations between allergen-specific IgE and IgGd levels to DF and DP. However, in contrast to IgE, allergen-specific IgGd in normal dogs was higher than in atopic dogs. Furthermore, a high percentage of the atopic population had detectable IgGd to unrelated allergens, despite negative IDSTs. Overall, the negative predictive values were similar for both IgE and IgGd. Sensitivities were higher in the allergen-specific IgGd assays, but the specificities and positive predictive values were higher in the allergen-specific IgE assays. In conclusion, the concordance of IDSTs with ELISA results to DF and DP in normal dogs without clinical signs implied the possible heterogeneity of IgE in dogs. The presence of IgGd directed against apparently irrelevant allergens in atopic patients and the high levels of IgGd in normal dogs to the most common allergens, DF and DP, implied an uncertain role of IgGd in canine atopic disease. Therefore, the detection of allergen-specific IgE is a more useful adjunct to the diagnosis of atopic disease in the dog than IgGd.     

Measurement of allergen-specific IgD and correlation with allergen-specific IgE

A new method for the measurement of allergen-specific IgD (as-IgD) was developed by modifying the ImmunoCAP assay (Pharmacia), and amplification of the signal with a goat anti-human/rabbit anti-goat detection system. The assay was sensitive enough to measure as-IgD in serum samples. The specificity of the assay was examined using inhibition tests with excess corresponding and non-corresponding allergens. For the different allergens inhibition rates between 56% (house dust mite) and 88% (cat) could be achieved. Non-corresponding allergens did not inhibit the as-IgD binding. Total IgE and allergen-specific IgE (as-IgE) was measured using the ImmunoCAP system. Total IgD was measured using a sandwich ELISA. As-IgD was measured in serum samples from 51 atopic and 23 non-atopic subjects, and the correlation with as-IgE was examined. As-IgD was detected in both atopics and non-atopics but at higher levels in atopics. As-IgD against birch pollen and timothy pollen allergen was found to be increased in atopics with IgE directed against these allergens compared to atopics without IgE against these allergens (P < 0.02 and P < 0.03). As-IgD against birch pollen allergen was higher in atopics with IgE specific to this allergen than in non-atopics (P < 0.02). In contrast to total IgE and total IgD, significant correlations were observed between as-IgD and as-IgE against timothy pollen (r = 0.34, P < 0.04), birch pollen (r = 0.38, P < 0.05) and cat dander allergen (r = 0.52, P < 0.01). The observed correlations between as-IgD and IgE suggest that IgD and IgE may be similarly regulated, and thus the measurement of as-IgD may give further insight into the regulation of IgE.