Late onset asthma in the elderly and its relationship with atopy.

Although asthma has always been considered as a disease of the early years, its presence is found both in old and young people. Asthma is often underestimated in the elderly because it can be confused with other diseases such as heart failure and, frequently, with COPD. In most cases asthmatic patients develop their disease before 45 years of age, but sometimes the first episode of asthma occurs after 60 years of age. This asthma phenotype is called Late Onset Asthma (LOA). LOA is often underestimated but, in recent years, some studies have shown that LOA is not entirely uncommon among the elderly; this clinical form is often caused by allergic sensitizations. The cause depends on the overall improvement of health in the most economically developed nations and also on the parallel increase in allergic diseases in these countries.

In vitro and in vivo biological activities of old and fresh Cupressus arizonica pollen.

BACKGROUND: Respiratory allergy to the pollen of Cupressaceae is becoming more and more common every year in the Mediterranean area. OBJECTIVE: The purpose of this study was to see whether the allergenic potency of Cupressus arizonica pollen diminished after a 6-year period (1994-2000). MATERIALS AND METHODS: Among the Cupressaceae, we selected the pollen of C arizonica. The mode of sampling in 1994 and in 2000 was the same and the pollen was collected on the same tree and stored at room temperature. To compare its biological and allergenic activities data was collected with the following methods: cytohistology of Alexander, 2,3,5-triphenyltetrazolium chloride enzyme staining, skin testing, nasal provocation test, radioallergosorbent test (RAST), RAST inhibition, sodium dodecyl sulfate polyacrylamide gel electrophoresis, and immunoblotting to detect protein content. Thirty-eight patients with respiratory allergy to Cupressaceae were selected. RESULTS: We found no decrease in the allergenic potency of the pollen, but did find that viability and germinating power had disappeared completely after 30 to 40 days. Moreover, the amount of protein in the old pollen was half the amount found in the fresh one. Skin prick testing showed identical results with the old and the fresh pollens. CONCLUSIONS: The allergenic in vivo and in vitro activity of cypress pollen is retained for years after its collection. This activity seems to be independent of the viability of pollen grains and of the total protein content. This may explain the presence of clinical symptoms in patients out of the pollen season.

Occupational respiratory allergy to cyclamen pollen: a case report.

A case of cyclamen (Cyclamen persicum) pollen allergy is described on a flower cultivator. The diagnosis was assessed by skin test, methacoline test, nasal provocation test and RAST. SDS-PAGE and immunoblotting have shown an intense response against a 18 kDa component and a weaker one at 100 Kda. A RAST inhibition against Cupressus sempervirens and Acacia floribundia showed no identity with cyclamen. This case confirm the cyclamen allergenity, in professional exposure. The nasal challenge prove to be very useful to confirm allergic sensitizations an we emphasize the necessity of preventive measures of protection for those florists who cultivate cyclamen plants.

Efficacy of sublingual coseasonal immunotherapy with a monomeric allergoid in Cupressaceae pollen allergy--preliminary data.

BACKGROUND: Respiratory allergy to conifers pollens is a growing phenomenon all over the world (Mediterranean area, USA, Japan). In France and Italy Cupressus sempervirens is the commonest offender. OBJECTIVE: To check the efficacy of specific immunotherapy by the sublingual route using a monomeric allergoid of Cupressus Arizonica pollen. MATERIAL AND METHODS: 20 patients and 10 controls were randomly selected. The diagnosis was assessed on a clinical hivernal symptomatology of allergic rhinitis, and/or asthma, positive skin test and RAST, and nasal provocation test to Cupressus arizonica. The extract was a monomeric allergoid titrated in allergenic units (AU). The treatment was coseasonal from the beginning of december to the end of march. It was not conducted double blind. RESULTS: The evaluation of the allergenic potency of native and modified Cupressus arizonica extracts have shown that the modified extract has a decreased skin test IgE binding capacity. According to symptom, drug consumption scores and nasal provocation test, there was a statistical improvement in the active group (compared to the control group) without any side effect. DISCUSSION: The use of a modified Cupressus arizonica extract, which is easier to prepare than Cupressus sempervirens and which is a monomeric allergoid, has shown that by the sublingual route, this therapeutic approach is safe and that the first results were satisfactory without any side effect. This good tolerance was anticipated by the fact that, checked on 16 volunteers by skin test, the allergoid gave a less important local reaction on skin testing than the native extract. CONCLUSION: This study has shown that: The KCNO modified Cupressus arizonica extract has a reduced IgE binding capacity; This monomeric allergoid is safe and effective administrated by the oromucosal route in clinical respiratory allergy to Cupressaceae and devoid of any side effect.

Immunological characterization of a recombinant tropomyosin from a new indoor source, Lepisma saccharina.

BACKGROUND: The presence of specific IgE antibodies to invertebrates is common among patients with rhinitis and asthma. Tropomyosin has been described as an invertebrate cross-reactive allergen. We have recently characterized an allergenic extract from silverfish (Lepisma saccharina). Since this insect could be a new source of tropomyosin in the indoor environment, we have thought important to clone and characterize the tropomyosin from it. METHODS: Recombinant tropomyosin was cloned and characterized by means of immunoblotting with tropomyosin-specific monoclonal antibodies, rabbit polyclonal antibodies and IgE from allergic patients. Its allergenic activity was investigated in histamine release assays. Immunoblotting and ELISA inhibition were carried out to identify the natural tropomyosin in the silverfish extract and to study the cross-reactivity among other arthropod tropomyosins. RESULTS: Tropomyosin-specific antibodies recognized in immunoblotting the natural tropomyosin in the insoluble fraction of silverfish extract. The silverfish tropomyosin (Lep s 1) was cloned and fully expressed. It shared high homology with other arthropod tropomyosins. rLep s 1 was recognized by tropomyosin-specific monoclonal and polyclonal antibodies and by IgE of allergic patients. It was able to inhibit the IgE binding to the insoluble fraction of silverfish extract, and to induce histamine release by an arthropod-allergic serum. Inhibition experiments revealed IgE cross-reactivity between rLep s 1 and other arthropod tropomyosins. CONCLUSION: rLep s 1 is the first allergen cloned and characterized from silverfish extract. It enabled us to identify the natural counterpart in the insoluble fraction of silverfish extract, suggesting that the tropomyosin is not readily extractable with a classic aqueous extraction procedure. rLep s 1 displayed biological activity, suggesting that it could be regarded as a useful tool to study the role of silverfish tropomyosin in the sensitization to invertebrate allergic sources.

Evaluation of cross-reactivity between Holoptelea integrifolia and Parietaria judaica.

BACKGROUND: Holoptelea integrifolia and Parietaria judaica belong to the family Urticaceae, but are geographically distantly located. H. integrifolia is an important pollen allergen of India and sensitizes almost 10% of the atopic population in Delhi. P. judaica, on the other hand, is a very dominant pollen allergen of the Mediterranean region, sensitizing almost 80% of the allergic population. Since both these important pollen allergens belong to the family Urticaceae, the objective of the present study was to assess cross-reactivity between these two pollen allergens from different geographical regions. METHODS: Cross-reactivity between these two pollen allergens was assessed on the basis of skin prick tests and ELISA, ELISA inhibition and immunoblot inhibition studies. RESULTS: Out of 44 atopic Indian patients skin prick tested with H. integrifolia extract, 34% were found to be sensitized. All the patients sensitized to H. integrifolia also showed varying degrees of skin positivity to P. judaica pollen extract. ELISA and ELISA inhibition studies suggested strong cross-reactivity between H. integrifolia and P. judaica pollen. Immunoblot inhibition studies revealed that 14-, 16-, 28-, 38-, 42- and 46-kDa proteins are the cross-reactive proteins in H. integrifolia and P. judaica. However, Par j 1, the major allergen of P. judaica, is absent in H. integrifolia pollen. CONCLUSION: H. integrifolia and P. judaica pollens share cross-reactive as well as unique epitopes. The major allergen of P. judaica, Par j 1, seems to be absent in H. integrifolia pollen allergen.

Efficacy and safety of specific immunotherapy to mosquito bites.

BACKGROUND: Adverse effects of mosquito bites are often very unpleasant and need a treatment. OBJECTIVE: To evaluate the efficacy of specific immunotherapy (S.I.T) with an extract of the whole body of the mosquito Aedes communis. METHOD: Twenty patients having strong local immediate and delayed reactions with in many cases also an allergic rhinitis, were selected. A similar control group was included. In all these patients skin tests, RASTs and nasal provocation tests were carried out with an extract of Aedes communis and a battery of the commonest allergens in our area including two insects : Blatella germanica (german cockroach) and Gasterophilus intestinalis (horse fly). The specific immunotherapy was carried out by the conventionnal subcutaneous route. RESULTS: After 18 months of S.I.T all the patients reported the disappearance of local reactions and symptoms of allergic rhinitis, which was correlated with a statistically improvement of symptom and drug consumption scores and a decrease of allergenic reactivity by the nasal provocation test. CONCLUSIONS: S.I.T with an extract of Aedes communis produced after 18 months of treatment a significant improvement of allergic symptoms, a decrease of symptom and drug consumption scores and of allergen specific nasal reactivity. S.I.T in mosquito bite allergy appears to be effective and safe in the treatment of both cutaneous and respiratory symptoms.

Preparation and characterization of silverfish (Lepisma saccharina) extract and identification of allergenic components.

BACKGROUND: Airborne insect antigens represent important aeroallergens which have been widely investigated. Although it has been demonstrated that house dust contains significant silverfish (Lepisma saccharina) levels, none of the extracts obtained so far has been extensively characterized. Thus, we have prepared and characterized a silverfish extract and investigated its IgE-reactive components by testing the reactivity of sera from patients allergic to inhalant insect allergens. METHODS: The extract from silverfish insect bodies was prepared by homogenizing frozen silverfish in Tris-HCl buffer. The soluble material (Sup) was filtered and the insoluble material (Ppt) was resuspended in 100 mM Tris pH 10.6. The two fractions were characterized by biochemical and immunochemical methods. IgE reactivity was investigated on both fractions before and after periodate treatment. RESULTS: Protein content and total carbohydrates was 2 and 3% w/w for Sup and 1 and 0.3% w/w for Ppt. The SDS-PAGE profile of the two fractions showed a different pattern in the MW range of 5-175 kD. Sup and Ppt, probed with allergic sera, showed a complex pattern of IgE reactivity. When periodate-treated fractions were tested, IgE reactivity was either completely abrogated, reduced or not affected, depending on the allergic serum employed. CONCLUSIONS: The results obtained indicate that the classic aqueous-extraction procedures that have been used up to now for other insects might not be completely satisfactory, since several allergenic components are not soluble at the normally used pH. We developed a dedicated extraction procedure allowing the detection of a certain degree of reactivity in sera negative to allergens extracted following classic procedures.

Cross-reactivities between date palm (Phoenix dactylifera L.) polypeptides and foods implicated in the oral allergy syndrome.

BACKGROUND: Date fruit and pollen antigens share a number of cross-reactive epitopes. Date pollen has been shown to cross-react with antigens from Artemisia, cultivated rye (Secale cereale), Timothy grass (Phleum pratense), Sydney golden wattle (Acacia longifolia) and Bermuda grass (Cynodon dactylon) pollen. The present study was carried out to examine any cross-reactivities between date palm polypeptides and antigens of some common foods and vegetables that have been implicated in the oral allergy syndrome (OAS). Because most of such cross-reactivities in other allergens are attributable to the presence of carbohydrate chains and profilin, their role was also investigated. METHODS: Fresh extracts of 20 common fruits and vegetables were prepared. Putative date profilins were isolated by affinity chromatography using a poly L-proline column. Date fruit extracts were digested by various endoglycosidases and the immunoglobulin (Ig)E binding of the postdigest products was assessed in immunoblots. Rabbit antisera to whole date fruit extracts, Timothy grass profilin and putative date profilins, as well as human sera from date sensitive individuals were used in immunoblotting, ELISA and in inhibition experiments. RESULTS: IgG, ELISA and immunoblot results with the different rabbit antisera and date-sensitive atopic sera showed several antigenic cross-reactivities and similar cross-reactivities were seen with birch, date and timothy grass profilins. IgE, ELISA and immunoblot experiments with pooled date sensitive human sera showed a range of cross-reactivities with some food extracts. A number of the IgE cross-reactivities could be inhibited after preabsorption of pooled sera with date extracts. Sixty-six percent of individual date hypersensitive human sera bound IgE in putative date fruit profilin and their pooled sera bound IgE in birch pollen profilin. IgE-binding of the endoglycosidase digested date fruit extracts to atopic serum pool was restricted to only a very low molecular weight band of 6.5-8 kDa. CONCLUSION: These results indicate that date palm polypeptides share cross-reactive IgG and IgE epitopes with a number of foods implicated in the oral allergy syndrome, bind to birch and Timothy grass profilins and bind IgE through glycosyl residues. The clinical relevance of these cross-reactivities needs to be further elucidated.

Comparison between the native glycosylated and the recombinant Cup a1 allergen: role of carbohydrates in the histamine release from basophils.

BACKGROUND: Cypress pollinosis is an important cause of respiratory allergies. Recently, the Cupressus arizonica major allergen, Cup a1, has been cloned and expressed. The native counterpart of this allergen has been purified and characterized by our group. It has been suggested that sugar moieties play a role in the in vitro IgE binding on Cupressus arizonica pollen extract. OBJECTIVE: To characterize the immunoreactivity of the recombinant major allergen in comparison with its native counterpart. To evaluate the role of carbohydrate moieties in the IgE-mediated in vitro histamine release from basophils by using the native glycosylated Cup a1 as compared with the recombinant one. METHODS: Recombinant Cup a1 was expressed in E. coli. IgE reactivity of Cupressaceae-allergic patients on the native as well as the recombinant molecule was investigated by immunoblotting, ELISA experiments and histamine release test from passively sensitized basophils. RESULTS: Fourteen out of 17 Cup a1-positive sera had IgE antibodies reactive with the native molecule only and lost their reactivity-after periodate deglycosylation of the allergen. Moreover, only native molecule was capable of inducing histamine release by this group of sera. Both the recombinant and the native molecules were recognized by three out of the 17 sera and were equally capable of triggering degranulation. CONCLUSION: A large number of sera reactive with the major allergen recognize carbohydrate epitopes only. IgE from these sera are able to induce histamine release from basophils and they might play a functional role in the clinical symptoms of allergy.

Efficacy of sublingual specific immunotherapy in Cupressaceae allergy using an extract of Cupressus arizonica. A double blind study.

BACKGROUND: non-injective routes of immunotherapy in respiratory allergy have being proposed as an alternative to conventional immunotherapy. We carried out a study to evaluate the clinical efficacy and effects sublingual immunotherapy (SLIT) in patient with Cupressaceae pollen respiratory allergy. METHODS: twenty patients with Cupressaceae pollen (C. sempervirens) rhinoconjunctivitis, mild asthma or both were randomly chosen for sublingual immunotherapy (10 patients) or placebo treatment (10 patients) using a double blind placebo controlled technique. We have used an extract of Cupressus arizonica because of its better stability in solution and its crossreactivity with Cupressus sempervirens. The patients underwent treatment for 12 months (from april 1999 to april 2000). Symptoms and drug scores as well as nasal provocation tests were recorded. The pollen counts were carried out, during all the same period. RESULTS: we found significantly lower symptom scores (p < 0.05) and drug consumption scores (p < 0.05) in the immunotherapy group than in the placebo group, during the pollen season, after the first year of therapy. Besides threshold of allergen reactivity in nasal provocation tests was increased in the active group (p < 0.01). No untoward reactions have been observed. CONCLUSIONS: SLIT with Cupressus arizonica (pollen extracts) produced, after one year treatment, a significant improvement of allergic symptoms and a decrease of drug consumption scores and allergen-specific nasal reactivity. SLIT with Cupressus arizonica appeared to be effective and safe in the treatment of Cupressaceae pollen respiratory allergy.

New clinical data and therapeutic prospects in Cupressaceae pollen allergy.

The authors emphasize, thanks to their clinical data over the last 20 years: The steady increase of allergy to C. sempervirens pollen compared to other pollinosis and to atopy. The frequency of cross-reactivity between C. sempervirens and other pollens belonging to Cupressaceae and Taxodiaceae families, in order, in the absence of a very good standardization and of a purification of this pollen, to try to undertake a sound specific immunotherapy using the most cross-reactive pollen mixed with C. sempervirens extracts. As a matter of fact the partially purified extracts of C. japonica gave the higher incidence (91%) of cross-reactivity. Consequently, a mixture of C. sempervirens and C. japonica extracts was used since 1993 with good results in a double blind study.

Allergy to date fruits: characterization of antigens and allergens of fruits of the date palm (Phoenix dactylifera L.).

BACKGROUND: Date-palm (Phoenix dactylifera L.) fruits are eaten daily by most inhabitants of the Middle East and the neighboring countries. Recent reports have indicated that dates are allergenic. This study aimed to investigate the antigenic and allergenic potential of date fruits. METHODS: Date-fruit extracts from eight cultivars were evaluated in skin prick tests (SPT) in an atopic population, used to produce antisera, analyzed by SDS-PAGE, and fractionated by gel-filtration chromatography. Sera from SPT-positive individuals were evaluated by ELISA and RAST, and in anti-igE immunoblot experiments. RESULTS: About 13% of patients were SPT-positive for at least two extracts. SDS-PAGE of whole extracts revealed 15-18 protein bands of 6.5->100 kDa, and Sephacryl S-200 fractions gave distinct peptide bands. RAST and anti-IgE ELISA gave a range of positive results, which could be abrogated when sera were preabsorbed with fruit extracts. IgE immunoblots of different extracts with pooled positive sera revealed different anti-IgE-binding immunoprints. All the positive sera from fruit-allergic and pollen-allergic individuals bound strongly to two anti-IgE reactive bands of 6.5 to 12-14 kDa and 28-33 kDa, respectively, and about 50% of sera bound to a 54-58-kDa band. CONCLUSIONS: These results strongly indicate that 1) date-palm fruit is a potent allergen 2) sera from fruit-allergic as well as pollen-allergic patients recognize common fruit-specific epitopes 3) there is heterogeneity in patient responses to the different extracts.

Efficacy and safety of oral immunotherapy in respiratory allergy to Parietaria judaica pollen. A double-blind study.

Two groups of 15 patients with respiratory allergy due to the pollen of Parietaria judaica were studied; one received a treatment of oral specific hyposensitization, the other one a placebo. All of them were monosensitized and clinically matched according to age, gender, score symptoms, drug consumption, skin test and RAST, and nasal or bronchial provocation test. The pollen counts were the same during this period. The study was double-blind and lasted 2 years. The clinical tests including score symptoms, drug consumption, and nasal or bronchial provocation test, revealed a statistically significant improvement in the treated group as compared to the placebo group. No side effects were observed.

Late onset asthma clinical and immunological data: importance of allergy.

In people over 65 years of age (mean age 72) late onset asthma (LOA) is often mistaken for chronic obstructive pulmonary disease (COPD). Furthermore, it is generally believed that true allergic asthma starts very seldom in old age and that, in this case, it is actually intrinsic asthma i.e., without any sensitization to aeroallergens. The aim of this study was to show that LOA is not an uncommon entity and is often allergic. Among a population of 1,888 subjects (over 65 years of age) in a general medicine ward we found 21 patients (1.1%) corresponding to this entity. The diagnosis of asthma was assessed according to clinical data, pulmonary function and nasal provocation tests, and blood eosinophilia. The diagnosis of atopy was assessed on total IgE, prick tests and RAST for the commonest allergens of our area. This group of 21 patients was compared to three groups of age-matched subjects including: 68 patients afflicted with chronic bronchitis, a group of 14 patients who had asthma before the age of 65 (presenile asthma), and 20 normal controls. A group of 15 asthmatics under age 65 was also included (young asthma mean age 37). We found a rather high incidence of allergy (72%), mostly to Dermatophagoides pteronyssinus, but also to the pollens Parietaria judaica, grasses and Olea europea. Although the average age (except in the young asthma group) and the severity of symptoms were the same in the four groups, unexpectedly mean RAST and skin test values were higher in LOA than in the two groups of young asthmatics and presenile asthmatics. It was concluded that LOA is not uncommon among elderly patients over 65, which is in contrast with most previous studies; 72% of our cases were allergic, the main allergens being mite, and Parietaria judaica pollen.