Clinical symptoms and results of skin test, RAST and bronchial provocation test in thirty-three papain workers: Evidence for strong immunogenic potency and clinically relevant 'proteolytic effects of airborne papain'

Seventeen out of thirty-three workers who have been exposed to airborne papain at their place of work regularly developed asthmatic symptoms such as shortness of breath, wheezing, coughing, sneezing, rhinorrhea and conjuctival irritation upon contact with this proteolytic enzyme. Investigations by RAST, skin test and bronchial provocation test proved IgE-mediated hypersensitivity to papain in fourteen symptomatic workers. Ten of these were in a screening investigation involving twenty-nine of the thirty-three workers; i.e. the incidence of IgE-mediated sensitization was 34.5%, of this group. Bronchial provocation of as little as 0.001–0.5 mg of papain was shown to elicit immediate or dual asthmatic reactions in all eight tested workers with RAST values > 3 u/ml. On the other hand, inhalation of 0.5 mg of papain did not cause any remarkable change in non-exposed asthmatics. Occupation-related blood-stained nasal secretions and/or cutaneous flare reactions in all four heavily-exposed papain workers, of whom three had negative skin test and RAST results, suggest a direct effect of the proteolytically active enzyme on human tissue. There was a significant elevation (P < 0.001) of serum trypsin inhibitory capacity in papain workers which seems to depend on the degree of exposure. No significant differences between symptomatic and asymptomatic workers in α₁-antitrypsin (Pi) phenotype subtypes were found.     

Allergic reactions, including asthma, to the pineapple protease bromelain following occupational exposure

A 58-year-old pharmaceutical worker regularly developed asthma and rhinitis when handling bromelain, a purified protease of pineapple (Ananas comosus), at her workplace, where she had been employed for about 10 years. RAST and prick test showed strong positive reactions to bromelain. Both inhalation test with 0.03 mg bromelain and peroral challenge by ingestion of 190 g pineapple resulted in asthmatic reactions; the latter challenge was accompanied by gastrointestinal symptoms. Five of six workers sensitized to papain, showed positive RAST and skin test results to bromelain, two of them also showed immediate asthmatic reactions after bronchial challenge with bromelain. Out of sixty asthmatics not exposed to airborne proteases but probably to these as constituents of foods, two had positive skin test results and eight had positive RAST results to bromelain; but in no case was there clear evidence for clinical sensitization. The presented data prove conclusively that bromelain is capable of inducing IgE mediated respiratory and gastrointestinal allergic reactions. Furthermore, there is evidence for immunological cross-reaction between the two plant proteases bromelain and papain in human subjects.     

Skin prick test and serological analysis with recombinant group 2 allergens of the dust mites L. destructor and T. putrescentiae

BACKGROUND: The dust mites Lepidoglyphus destructor and Tyrophagus putrescentiae are important sources of allergen in farming environments. The major allergens of the dust mites L. destructor and T. putrescentiae have been cloned and expressed as recombinant proteins. OBJECTIVE: To evaluate the use of recombinant group 2 allergens of L. destructor (rLep d 2) and T. putrescentiae (rTyr p 2) in skin prick test (SPT), and serological analysis in sensitized and non-sensitized farmers chronically exposed to dust mites. METHODS: Skin prick test with rLep d 2, rTyr p 2 and the corresponding commercial extracts was performed in 44 farmers sensitized to L. destructor and/or T. putrescentiae, and 38 control farmers. IgE and IgG subclass antibodies to the recombinant allergens were analysed by RAST and ELISA, respectively. RESULTS: Out of the 44 subjects positive in SPT to L. destructor and/or T. putrescentiae extract, 26 (59%) displayed a positive SPT to one or the other of the recombinant allergens, whereas 21 (48%) were positive to both. Significant correlations were registered between the sizes of the weals induced by rLep d 2 and rTyr p 2 and the corresponding RAST values (P < 0.001). A majority of subjects positive in SPT to the recombinant allergens had detectable IgG4 antibodies, and the levels were significantly higher in the dust mite sensitized group than in the controls (P < 0.05). No such differences were found in the IgG1 values (P > 0.05). The results obtained with rLep d 2 and rTyr p 2 correlated relatively well with each other with respect to SPT, RAST and IgG4, suggesting that the allergens have similar or shared IgE epitopes. All the control subjects had a negative SPT and RAST to rLep d 2 and rTyr p 2. CONCLUSION: Recombinant group 2 allergens from the dust mite L. destructor and T. putrescentiae represent useful tools for diagnosis of dust mite allergy.     

Papain-induced asthma: diagnosis by skin test, RAST and bronchial provocation test

Seven out of eleven workers occupationally exposed to airborne papain developed immediate hypersensitive reactions, predominantly asthma and rhinitis. Skin tests and RAST with papain were positive in all symptomatic workers, but not in the four asymptomatic workers. Furthermore, out of forty non-exposed asthmatics, thirty-eight had negative RAST results and all had negative skin test results. Bronchial provocation tests with 0.15–0.5 mg papain performed in five patients with a positive case history showed in each case an immediate asthmatic reaction; in addition to that, one patient developed signs of a dual asthmatic reaction. Our results suggest that airborne papain is a highly immunogenic agent in humans, which induces type I allergic reactions in a large percentage of the exposed subjects.     

Anaphylaxis to excipient mannitol: evidence for an immunoglobulin E-mediated mechanism

BACKGROUND: Anaphylaxis to mannitol present naturally in pomegranate and cultivated mushroom in a sensitized subject has been described recently, and an IgE-mediated mechanism to this sugar alcohol has been proposed. The same subject also experienced severe allergic reactions to a chewable pharmaceutical (cisapride drug). OBJECTIVE: The purpose of the study was to identify allergenic component in the pharmaceutical preparation, and also, to understand the mechanism of immediate hypersensitivity to mannitol. METHODS: Methodology involved skin prick tests (SPTs), high-performance liquid chromatographic (HPLC) analysis of pharmaceutical preparations, separation of mannitol by Ca++-ion-moderated cation-exchange chromatography, preparation of alditol-protein conjugates by reductive amination, SPT using the conjugates, hapten affinity purification of the allergic serum on D-mannitol-keyhole limpet haemocyanin (KLH)-Sepharose CL-6B, and detection of serum mannitol-specific IgE by ELISA. RESULTS: Component testing by SPT, and HPLC analysis of various pharmaceuticals indicated that the excipient mannitol is the causative allergen. Mannitol separated from Cisapid MPS showed allergenic activity by SPT. Among the several conjugates tested by SPT, D-mannitol-bovine serum albumin and D-mannitol-KLH showed positive weal/flare reaction, demonstrating the presence of cell-bound mannitol-specific IgE in vivo. Negative results with D-glucitol, D-galactitol, meso-erythritol, and L-mannitol protein conjugates clearly showed that the mannitol-specific human IgE is very specific to the D-isomer of mannitol. ELISA using the hapten affinity-purified allergic serum was positive, demonstrating the presence of mannitol-specific serum IgE in the allergic subject. CONCLUSION: Mannitol, which is widely used as a food and drug additive (excipient), can rarely cause IgE-mediated anaphylaxis. This study is the first one to demonstrate the presence of mannitol-specific human IgE in a sensitized allergic subject to validate an IgE-mediated hypersensitivity mechanism for mannitol.     

Papain-induced allergic reactions

Papain is a proteolytic enzyme with elastolytic activity, which produces emphysemalike lesions when introduced into the airways of animals. It is encountered by humans in numerous occupations, medications and domestic products. Sensitization to papain in two subjects in different occupations was confirmed with skin tests with chemical-grade papain and radioallergosorbent tests (RAST), with a papain which had been chemically inactivated by selective active site blockade. Skin tests and RAST were negative in non-symptomatic co-workers. Withdrawal from occupational exposure to papain resulted in an improvement in symptoms. In a survey of 330 subjects at the time they were receiving routine allergy skin tests, seven reacted to papain. Sensitization was confirmed by the RAST. Serum IgG antibodies to papain were detected among sensitized individuals and also in five out of 266 sera obtained from a clinical hospital laboratory. The findings illustrate immune responses to papain in humans in the form of atopic sensitization and serum IgG antibodies. Moreover, recurrent respiratory symptoms in the presenting persons served to illustrate that they and their co-workers were repeatedly exposed to air-borne papain. In view of the potential danger from the proteolytic effects of papain, these observations illustrate the need for further investigations of the effects of human exposure to air-borne papain.     

The significance of hypersensitivity to nuts in patients with birch pollen allergy

This study was performed in patients with allergic rhinitis/conjunctivitis to birch pollen to determine whether patients with additional hypersensitivity to nuts and apples differed from patients without such hypersensitivity; the determination was in terms of results of skin prick test (SPT), specific IgE antibodies (RAST), and symptoms during the pollen season. Forty-seven patients with birch pollen allergy were investigated by RAST against birch and hazel pollen and by SPT. They were treated in a randomized, double-blind, placebo-controlled study with fluticasone propionate aqueous nasal spray or placebo. The area of the SPTs was larger and the specific IgE values higher in patients with hypersensitivity to nuts and apples. These patients also had more symptoms during the pollen season. We conclude that hypersensitivity to nuts is an indication of a more severe allergy in patients with birch pollen allergic rhinitis.     

Allergy to the pine processionary caterpillar (Thaumetopoea pityocampa)

BACKGROUND: The contact with the pine processionary caterpillar (Thaumetopoea pityocampa) induces dermatitis and ocular lesions by a mechanic and toxic mechanism. However, IgE-mediated hypersensitivity to this caterpillar has been demonstrated in two recent studies. OBJECTIVE: To find if an IgE-mediated mechanism was operative among patients with suspected previous reactions to processionary caterpillars, particularly exposed workers. METHODS: Fifty-five patients were studied by skin prick test (SPT), and specific IgE detection by immunoblotting. RESULTS: A total of 58.18% patients had a positive SPT for caterpillar extract. Positive SPT patients had more generalized cutaneous reactions (47%) and oedema (50%) as well as a shorter latency period (mean, 36 min) and duration of cutaneous lesions (mean, 26 h) than the patients with negative SPT. A total of 60% of the positive SPT patients had occupational exposure to the processionary caterpillar. The occupationally exposed workers showed significant symptoms from October to December. The anaphylactic reactions only appeared in allergic patients with occupational exposure and were also more frequent from October to December. These patients with anaphylactic reactions had a major size of SPT and the exercise was found in them to be a variable that increased the symptoms. The IgE immunoblot detected in the caterpillar extract several reactive bands with apparent molecular weights from to 35-4 kDa in 72% of the cases with positive SPT. CONCLUSIONS: Allergic reactions to T. pityocampa urticating hairs have different clinical characteristics than those induced by a toxic-irritative mechanism and are more frequent than suspected. Allergic reactions to this caterpillar among occasional visitors to pine-wood areas, and particularly in pine-forest workers, should be taken into consideration by allergists.     

Antigens of Euparipha pisana (snail). I. Identification of allergens by means of in vivo and in vitro analysis

The data obtained in this study suggest that eating Euparipha pisana (snail), a common food in Mediterranean countries, could give serious allergic reaction such as asthma. We describe here the identification and partial characterization of allergenic molecules form this new source. An aqueous extract of snail was obtained by homogenization in distilled water, centrifugation, dialysis and defatting with ethyl ether. Skin prick test (SPT) performed with the snail extract on 70 subjects allergic to the more common allergens of the Mediterranean area gave a SPT positivity in 61% of the subjects tested, with a mean value of histamine-equivalent prick (HEP) equal to 0.81 +/- 0.25 (n = 43), while no SPT-snail-positive reactions were obtained by using the same extract on 30 not allergic subjects. To ascertain if such a sensitivity was IgE-mediated, sera from SPT-snail-positive subjects were analyzed by RAST, coupling the snail extract to polystyrene balls and to paper discs. 19% of the sera tested were RAST-positive, mean value of binding 4.8 +/- 2.8% (n = 13), while when using sera from SPT-snail-negative subjects, the RAST mean value was 0.49 +/- 0.18% (n = 27). Histamine release (HR) was also performed. Basophils prepared from SPT-snail-positive subjects were incubated with a snail extract. All of the SPT-snail-positive subjects gave a significant value of HR, mean value 21.8 +/- 7% using 1 micrograms of snail extract (n = 16), while 1.41 +/- 1.1% (n = 10) was the mean value obtained when SPT-snail-negative subjects were analyzed.(ABSTRACT TRUNCATED AT 250 WORDS)     

Preparation of a proteolytic enzyme mixture containing trypsin,elastase, and chymotrypsin for use in tissue disaggregation

Summary We describe a purification method for tissue culture-grade trypsin that yields an enzyme mixture with reproducible activities of trypsin, elastase, and chymotrypsin and eliminates amylase and lipase.     

Occupational allergy to weeping fig in plant keepers

Plant keepers take regular care of green plants in public buildings and offices. One of the most common green plants in Scandinavia is weeping fig (Ficus benjamina). We have previously reported on two plant keepers sensitized to this plant, one had asthma and the other allergic rhinitis. We now report a study of four plant-leasing firms employing 60 plant keepers and 24 less exposed. Positive RAST and skin tests in 16 of the plant keepers and two of the employees showed them to be sensitized. All sensitized subjects suffered from conjunctivitis and/or rhinitis and six had asthma. Handling of green plants is a new example of an occupation which may cause IgE-mediated allergy.     

Dog serum albumin as an allergen. IgE, IgG and lymphocyte responses in dog dander-sensitive asthmatic children

To study the allergenicity of dog serum albumin (DSA) in dog-sensitive subjects, we investigated 203 asthmatic children by means of the skin prick test (SPT), the radioallergosorbent test (RAST) and the in vitro lymphocyte stimulation test. Significant SPT reactions to DSA were observed in only 9 out of 80 subjects with a significantly positive SPT reaction to dog dander and hair (DDH). Analogously, positive DSA RAST results were observed only in a minority of the cases with a positive DDH RAST. Significant SPT reactions to DSA were not observed in subjects with a negative clinical history of dog allergy, or in subjects with a negative reaction to DDH in the SPT or in the provocation test. DSA induced remarkable lymphocyte stimulation in only 1 subject, who also had a significant SPT reaction to DSA. DSA-specific serum IgG antibody titers measured by ELISA were not found to correlate with DSA SPT or DSA RAST.     

Characterization of soybean allergens causing sensitization of occupationally exposed bakers

Fourteen bakers suffering from workplace-related respiratory symptoms and sensitized to soybean were studied. Twelve of them were also allergic to wheat flour, 10 to rye flour, and five to α-amylase of Aspergillus oryzae (Asp o 2). IgE estimation by RAST strongly indicated that the trypsin inhibitor and lipoxidase are major allergens of soybean. Various allergenic components could be characterized by immunoblotting after two-dimensional electrophoresis. Our RAST and immunoblotting results show an interindividually different allergic response to inhalative soybean constituents, and that the trypsin inhibitor (20 kDa, pI ∼4.5) is an important inhalative soybean allergen recognized by IgE antibodies in the sera of 86% of the examined sensitized bakers.     

Limpet anaphylaxis: cross-reactivity between limpet and house-dust mite Dermatophagoides pteronyssinus

BACKGROUND: Limpet is a mollusc that is frequently found along the shores of warm seas. Few allergic reactions to limpet have been described, and cross-reactivity with house-dust mites has not been established. METHODS: We report five patients with anaphylactic reactions due to limpet ingestion. A limpet extract was prepared and skin prick tests (SPT), radioallergosorbent assays (RAST), sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and IgE-immunoblotting were performed. In order to evaluate cross-reactivity, an immunoblotting inhibition assay with Dermatophagoides pteronyssinus was also done. RESULTS: All patients were asthmatics sensitized to house-dust mites. In each case, severe bronchospasm was evidenced, and three required mechanical ventilation. Positive SPT with limpet extract was found in the four patients tested. RAST showed specific IgE on each patient's sera. Immunoblotting showed several allergenic fractions with a wide molecular weight range (15-250 kDa). D. pteronyssinus inhibited IgE-binding molecules above 50 kDa in the limpet extract, particularly one molecule of 75 kDa. CONCLUSIONS: We describe five patients with IgE-mediated limpet allergy. Severe bronchospasm was the most important symptom. Cross-reactivity with D. pteronyssinus was demonstrated.     

Respiratory allergies (bronchial asthma and rhinitis) due to sensitization of type I allergy to red spider mite (Panonychus ulmi KOCH)

The inhabitants of a fruit growing area often report spontaneously of sensitization to the red spider mite (RSM) (Panonychus ulmi KOCH). These are for the most part sensitizations with low clinical symptoms (rhinitis, conjunctivitis and erythema). Severe clinical developments with bronchial asthma have been observed. We investigated six patients working in a fruit growing area sensitized by RSM. The sensitizations corresponded to a Type I allergy. Skin tests and provocation tests (nasal as well as bronchial) with RSM showed immediate reactions and RAST positive results were obtained using RSM allergen disks. RAST measurements of sera from nine house-dust mite Dermatophagoides pteronyssinus allergic patients using RSM allergen disks showed RAST-class > 1 for eight patients. RAST inhibition and immunoprint suggest a possible cross-reaction between RSM and D. pteronyssinus.     

Evaluation of papain/chymopapain cross allergenicity

Recent clinical evidence suggests that papain and chymopapain may share common allergenicity. Patients that become sensitized to papain may subsequently experience an allergic reaction when they are exposed to chymopapain. This study demonstrates a cross antigenicity between the proteolytic enzyme preparations papain and chymopapain. Serum samples from six patients who demonstrated 4+ skin reactions to papain also revealed positive RAST ratios to both papain and chymopapain. In addition, serum samples from 12 clinically nonreactive patients who had discolysis with chymopapain demonstrated positive RAST results to papain as well as to chymopapain.     

IgE-mediated anaphylactoid reactions to rubber

Delayed hypersensitivity to rubber chemicals is well known, but there are only a limited number of case reports on an immediate type of hypersensitivity inducing contact urticaria. We have recently seen several patients with rubber glove-induced contact urticaria who have had both positive skin prick tests and positive RAST tests to natural latex from the rubber tree (Hevea brasiliensis). We now report on five patients who also developed systemic reactions. It is clear that sensitized subjects are at risk of developing anaphylaxis during medical examination or surgery when rubber gloves are used. The occurrence of IgE-mediated allergy to rubber is probably underestimated.     

IgG hydrolysis in abscesses: I. A study of the IgG in human abscess fluid*

Human abscess fluids have been shown to contain Fc and Fab fragments of IgG. The Fab fragments were able to inhibit chymotrypsin and subtilisin agglutinators but not pepsin, papain, ficin, bromelin, or trypsin agglutinators. The levels of proteolytic enzymes in abscess fluids were measured and shown to be high.     

IgG hydrolysis in abscesses: II. Hydrolysis of Ripley IgG by enzymes from abscess leucocytes

Hydrolysis of Ripley IgG at pH 4.5 and pH 8.0 by leucocytes isolated from human abscesses gave rise to Fab fragments which showed an antigenic specificity resembling that characteristic of Fab fragments produced with the enzymes subtilisin, chymotrypsin and bromelin. At neither pH did the hydrolyses give rise to Fab fragments with an antigenic specificity characteristic of Fab fragments produced by the enzymes pepsin, papain or trypsin.     

Occupational allergy caused by flowers

We describe 14 consecutive patients with complaints due to the handling of flowers. The symptoms varied from allergic rhinoconjunctivitis and asthma to urticaria. Most patients had professions in the flower industry. Skin prick tests (SPT) were performed with home-made pollen extracts from 17 different flowers known to be the most commonly grown and sold in The Netherlands. RAST against mugwort, chrysanthemum, and solidago was performed. The diagnosis of atopy against flowers was based on work-related symptoms due to the handling of flowers, positive SPT with flower extracts, and positive RAST The concordance between SPT and case history was 74%, and that between SPT and RAST was 77% Extensive crosssensitization was seen to pollen of several members of the Compositae family (e.g., Matricaria. chrysanthemum, solidago) and to pollen of the Amaryllidaceae family (Alstroemeria and Narcissus). Homemade flower extracts can be used to confirm IgE-mediated flower allergy. Mugwort can be used as a screening test for possible flower allergy. For most patients, the allergy led to a change of profession.