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Atopic dermatitis is no longer a constitutional illness that cannot be influenced. The discovery of IgE fixed to the cells of Langerhans changes the physiopathological concept of this illness. There must be a minutely careful search for all the possible etiologies before advising therapy or long-term treatment. Attention must be given to the role of foods, discovery of causal pneumoallergens and a systematic search for a contact allergen must be made. This systematic and scrupulous search also gives confidence to a patient who is discouraged by the development of the condition.

Monoclonal antibodies (PpV4) raised against Phleum pratense group V allergen were used for immuno-affinity chromatography of cross-reacting group V allergens from related grass species. Fractions enriched in group V allergen were obtained from Lolium perenne, Poa pratense and Dactylis glomerata extracts. The major components in these fractions were found in the Mwr range 25-28 kD. IgE binding to these components was shown using a pool of grass allergic sera, by SDS-PAGE immunoblotting. These fractions were electroblotted from tricine SDS-PAGE gels onto a polyvinylidene-difluoride membrane and selected group V bands were directly cut out and used for amino acid analysis and NH2-terminal sequencing. Both the amino acid compositions and the NH2-terminal sequences obtained for each group V allergen were almost similar to each other and to the sequence and composition of the previously described allergen Phl p V from Phleum pratense. A common trait of the investigated allergens, is the very high contents of alanine (25-32%) and the presence of the modified amino acid, hydroxyproline.

The guinea-pig maximization test (GMPT) has been in use as a method for the prediction of skin sensitization potential for over 20 years, and is widely accepted by regulatory authorities because of its reliable detection of a wide variety of potential human contact allergens. Nevertheless, the method has some limitations and drawbacks, including the use of an adjuvant, the injection of the test substance at induction thus bypassing the normal skin barrier and metabolic function, a subjective endpoint, interference by irritant and/or coloured chemicals, and a relatively long and complex protocol. To address these points, an alternative technique, the local lymph node assay (LLNA), has been proposed and has become the focus of much attention. Recent data from interlaboratory trials have shown a good level of agreement between test facilities and with existing guinea-pig data. The present work investigated the correlation between LLNA results and those derived from the GPMT for 40 chemicals covering a range of chemical types and levels of skin sensitization potential. The LLNA assay was capable of detecting chemicals that exhibit a strong sensitization potential in the GPMT. For chemicals classified as moderate sensitizers in the GPMT, the LLNA was usually positive or provided an indication of sensitizing activity (that was not sufficient to satisfy the current criteria for regarding the result as positive). Weaker sensitizers in the GPMT were usually not detected by the LLNA. With the single exception of copper chloride, non-sensitizers were not positive in the LLNA. The results support the view that the LLNA can provide a rapid and objective screening test for strong sensitizers.

In an earlier study an allergen from Phleum pratense (timothy) pollen, Phl p V, has been isolated and physicochemically characterized. In this study Phl p V and immunochemically similar components from other grass pollens (group V allergens) have been investigated using immunoelectrophoretic techniques. To study the allergenic importance of the group V allergens, the allergenic compositions of 10 grass pollen extracts were investigated in crossed radioimmunoelectrophoresis (CRIE) using 20 sera from grass pollen-allergic donors. Group V allergens were identified using monospecific rabbit antibodies raised against Phl p V, anti-Phl p V, which react with other group V allergens usually producing dense precipitates in immunoelectrophoresis. In this way group V allergens were identified in eight extracts, and when present the precipitate corresponding to the group V allergen was the dominant IgE binding precipitate. All identified group V allergens bound IgE in at least 17 of the 20 investigated sera. Monospecific rabbit antibodies raised against the group I allergen of Lolium perenne (rye grass), anti-Lol p I, do not precipitate group V allergens, indicating that there are no immunochemical similarities between group I and group V allergens. In SDS-PAGE anti-Phl p V identifies IgE-binding components with molecular weights between 26 and 33 kD. In contrast, anti-Lol p I binds to components of slightly higher molecular weight. Apparently, the group V components are allergens that are physicochemically and immunochemically distinct from group I allergens.

138 patients from the state of Oaxaca, México, 75 male, 62 female, with an average age of 29 years with diagnosis of asthma rhinitis and sinusitis, were studied to determine the frequency of aeroallergens involved. Scratch tests were carried out with glycerinated antigens, 1:20 w/v Hollister S. The findings show house dust mite to be the allergen most frequently present, followed by house dust, cynodon d and rye grass.

In an attempt to assess whether or not the availability of inhalant allergens for diagnosis and treatment of allergic diseases in Japan is adequate, we tested 21 Japanese patients with allergic rhinitis or bronchial asthma against 75 inhalant allergens commonly used in the United States of America. These 21 patients had never lived outside of Japan and came to the United States for the purpose of diagnosis and treatment of their allergic diseases. We determined the importance of each allergen by calculating an allergenicity index. Allergenicity index for a given allergen was defined as a sum of a multiple of each of 4 grades of prick test reactions to the allergen and a number of patients reacting to the allergen with each corresponding grade. Mite had the highest allergenicity index, followed by house dust. All 14 pollen allergens occupying the 3rd through 12th ranks including many grass and weed pollens are not available for immunotherapy in Japan. Japanese cedar pollen which is considered the most important pollen allergen in Japan ranked the 13th. Of a total 25 allergens occupying from the 1st through 13th ranks 22 allergens are not available for immunotherapy including the most important allergen, mite. These results suggest that we should expand the list of allergens available for diagnosis and treatment of allergic diseases in Japan.

During the last 10 years, tremendous advances in the identification and characterization of allergens from a variety of substances have occurred. In this review, methods of allergen characterization and classification, as well as the effect of recent developments in biotechnology on allergen research, will be addressed. Prior to allergen isolation and characterization, adequate source material must first be identified. Most allergens that have been isolated are in the molecular weight range of 15,000 to 40,000 daltons and appear to be proteins or glycoproteins with acidic isoelectric points. A number of laboratory techniques have been shown to be extremely useful in identifying offending allergens and quantitating them in complex allergen extracts. Recently developed in vitro methods such as Western blotting, immunoprinting, and production of monoclonal antibodies to specific allergens will provide useful information for future analysis and standardization of allergen extracts. The effects of new technology on future developments in allergen characterization are far reaching. An important area of molecular biology that has only begun to be used in allergen research is the ability to clone and sequence DNA which codes for specific allergens. This facilitates the production of specific quantities of purified allergens provides material to determine their amino acid sequence, and allows production of standardized allergen preparations. Thus, it is conceivable that molecular biological approaches to allergen research will enable one to investigate the allergenic response at a molecular level and ultimately provide purified allergens in amounts sufficient for diagnosis and therapy.

Many or most allergen extracts available for clinical use are unacceptable for use in human medicine. Informed physicians refrain from using them in hyposensitization. We demand that regulations and control as to quality and standardization be enforced by the appropriate authorities without further delay. We have to compromise with the ideal to satisfy minimal requirements. Recommendations are presented.

Investigations of cross reactions between a cat hair and skin scraping extract (CHSS) and a cat serum (CS) were done by several biochemical and immunochemical methods. Furthermore, we looked for common allergenic molecules in a cat 1 reference preparation and in a CS. In crossed (radio) immunoelectrophoresis (CIE/CRIE) of CHSS vs. anti CS-serum one to eight allergen bands could be detected depending on the human serum employed. By constructing allergograms from the CRIE patterns of 17 patients' sera one out of eight allergens could be defined as a major allergen. CRIE of the cat 1 reference vs. anti CS-serum, using the sera of two cat allergic patients, displayed four to nine allergen bands, indicating that the cat 1 reference is not a pure preparation but rather an enriched fraction.

The classification of industrial chemical allergenic compounds has been developed. The criterion of noxious effect of allergenic chemicals is described not only by experimentally valid allergenic signs of the compound but also by clinical manifestations of allergosis in workers and sanitary diagnostic reliability of occupational allergic diseases. Numerous allergens are classified according to the chemical systematization of compounds. The classification contains 2 classes: the 1st class involves inorganic and elementoorganic compounds, the 2nd one--organic compounds. The first class has 7 subclasses, each of them covers compounds of one of the series of the 2nd-6th periods of Mendeleeff's periodic table. The second class has 3 subclasses, combining the compound derivatives of acyclic (2.1), aromatic and alicyclic (2.2), and heterocyclic hydrocarbons (2.3).

In order to determine the allergenic activity of five purified horse allergens, 22 children allergic to horses according to history, skin test, and leukocyte histamine release were evaluated. Washed leukocytes from all patients were tested for allergen-induced histamine release utilizing four epidermal horse allergens (Ags 6, 9, 11, and 15) and horse serum albumin. Crossed radioimmunoelectrophoresis was carried out with a standard horse dander extract and serum from each patient. The results showed considerable variation in the individual allergoprints. Ag 11 had the highest mean allergenic activity. Sensitivity to horse serum albumin was demonstrated three times. Our data show that the amount of serum IgE antibodies bound by horse allergens correlates significantly with the capacity of the allergens to induce histamine release from washed leukocytes.

With the conventional, discrete RAST various tests are required to detect IgE of different specificities in the same serum. To overcome this problem and to reduce the costs, a multiple RAST with seven different mixtures was compared with the individual mixture constituents and with the 12 individual allergens currently in use in our department. One grass pollen mixture (gx3), two weed pollen mixtures (wx3, wx4), two tree pollen mixtures (tx5, tx6), one mould mixture (mx1) and one epithelial mixture (ex1) were used. A mixture of mites was not evaluated as there is only one important pathogenic organism in our regions (Dermatophagoides pteronyssinus or House dust mite). For grasses the gx3 mixture offered no advantage over the discrete RAST. The weed mixture wx3 was more sensitive than the most common discrete RAST's but at the cost of specificity. The wx4 mixture should not be used because the specificity is too low. The tree mixtures were not significantly more sensitive than the most common individual tree allergens, and were less specific. Mould mixtures should not be used because there is little cross-reactivity between the individual allergens, thus using a mixture would necessitate the subsequent determination of individual allergens, and the number of tests and the cost would be even higher. Neither should a mixture be used for epithelia because one wants to detect allergies to individual allergens. Moreover, the sensitivity of the epithelial mixture was too low. In general, we suggest the use of a limited panel of discrete RAST's instead of mixtures.

Repeated exposure to garlic dust induced severe asthma in an atopic patient. Subsequently, the patient also developed marked adverse responses after ingestion of garlic. Immunologic investigations carried out in an asymptomatic period revealed significant skin reactivity and bronchospasm after challenge with both garlic dust and extract. The results of a controlled oral challenge test to garlic dust were also positive. The patient's serum contained unusually high quantities of garlic-specific IgE. Cross allergenicity between garlic and other members of the Liliaceae family were documented by the RAST inhibition technique.

Different subgroups of egg-allergic patients were established according to differences in allergic symptoms provoked by hen's egg white, total IgE-level, RAST (radioallergosorbent test) results to egg white, and age. In each group the pattern of specific IgE-antibodies to individual allergens in the egg white, determined by means of crossed radioimmunoelectrophoresis (CRIE), was compared with the pattern in a control group. The RAST value to egg white was found to exert the strongest influence on the CRIE results. A few statistically significant differences in CRIE results to certain allergens were also observed in other pairs of subgroups of egg-allergic patients. Possible explanations for this are discussed. It was concluded that CRIE studies of allergens in mixed protein solutions, using a series of sera from allergic patients, will most probably give the same results and the same classification of the allergens independent of the characteristics of the patients from which the sera were collected. However, it should be emphasized that the CRIE series must include a sufficient number of patients with high RAST values to the allergen in question. Otherwise some allergens may be missed and the classification of the allergens may be different.

Some recent works currently give some solid scientific basis to suppose that immunization with appropriate antigens might be beneficial for asthmatic patients. As numerous studies have now shown on the one hand that there was a relation between allergy, inflammation and bronchial hyper-reactivity and in the other that desensitization was able to modify the liberation of mediators to inflammation and the responses attributed to these mediators. The number of controlled studies performed up till now with the principal allergens are, for asthma, insufficient. However, no-one currently doubts the efficacy of specific desensitization to spasmodic pollen coryza. For pollen asthma, six studies conclude that there were superior results with desensitization than to placebo. Two studies showed no difference. Four controlled studies made for episodic house dust mite coryza ended with a favourable result. In allergic bronchial asthma to the dust mite, nine studies were favourable and five showed no benefit. It should be mentioned at this stage that all the studies on children have shown favourable results. There are few studies on the efficacy of desensitization to animal squamae (epithelial debris). Nevertheless, a very recently published study has shown, using cat squamae, clinical efficacy on bronchial, nasal and ocular symptoms. Desensitization with mould extracts cannot be judged at present, published controlled studies on the subject are almost nonexistent. On the other hand at the moment one can say that with microbial antigens non-standardised antigens, no clinical evidence has been shown to date. Incidents and accidents encountered during specific desensitization in respiratory allergy are extremely rare but may be serious.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative results between positive patch tests found during the periods 1968-1974 and 1975-1981 are presented. The number of sensitised patients to nickel, chromate and Peru balsam has significantly increased. On the other hand, the number of turpentine-oil-positive patch tests has strongly decreased. This mirrors the drop in the imported quantities of this product. A schema concerning factors influencing the apparent allergenicity is given.

Most of the major allergens that have been isolated from laboratory and domestic animals have been found to be acidic proteins, with molecular weights lower than that of serum albumin (Table II). Recent advances in characterization of antigens from these animals have emphasized that urine and saliva can be as important as epithelia as sources of relevant allergens. Urinary protein allergens are found in mice, rats, guinea pigs and rabbits, whereas cat saliva contains all the major allergens found in cat pelt extract. Urinary proteins from mice, rats and guinea pigs and salivary proteins from cats have been identified in air samples of rooms inhabited by these animals. There is now sufficient immunochemical data to standardize allergens from mice, rats and cats for diagnosis and immunotherapeutic trials.

Basidiomycete allergens have received scant attention to date, compared to allergens from deuteromycetes. This is true even though in previous studies, 32% of atopic patients with respiratory allergies were skin test reactive to basidiospore extracts. Since sufficient quantities of Calvatia cyathiformis spores were available, their allergens were sequentially fractionated by gel filtration (GF) and hydrophobic interaction chromatography (HIC). Unfractionated extract (crude), GF, and HIC fractions were electrofocused in polyacrylamide gel (pH 3.5 to 9.5) and immunoprinted onto CNBr-activated nitrocellulose (0.2 microns) filters. Sera from 19 skin prick test positive and 10 negative subjects, with comparable total IgE levels, were used to screen individual strips of each blot. Blots were reacted with 125I-labeled anti-IgE and analyzed by autoradiography. IgE from 79%, 89%, and 89% of the positive sera bound to crude extract, GF, and HIC, respectively; IgE from none of the negative sera bound to crude extract. A series of bands (pH 3.6 to 4.6) reacted with 63%, one band (pH 6.6) reacted with 68%, and one band (pH 9.3) reacted with 63% of the sera tested. These studies demonstrate at least three important groups of allergens in C. cyathiformis spores. This characterization allows assignment of initial C. cyathiformis allergen designations and development of a purification protocol.

This article presents a nomenclature system for allergens which has been officially recommended by the International Union of Immunological Societies (IUIS). The nomenclature is based on proposals of the IUIS Sub-Committee for Allergen Nomenclature and is applicable to highly purified, well-characterized allergens and to non-purified or partially purified allergenic extracts.

In a 3-year prospective double blind study, grass pollen allergic patients were allocated to perennial hyposensitization with the timothy major allergens Nos. 19 and 25 (2-component extract) or a 20-component timothy extract. The extracts were biologically standardized and adsorbed to aluminium hydroxide for treatment. Systemic side effects (SSE) had début after 1 1/2-5 h and lasted without treatment 1/2-10 h. Treatment with the 2-component extract showed preponderance of minor SSE (arthralgia, rhinitis, tiredness, headache, conjunctivitis, nausea, flu-like symptoms), but major SSE (urticaria, angioedema, asthma) were equally distributed between treatment with the two timothy extracts. Major SSE complicated the treatment before the first grass pollen season in 33% of the patients vs. only in 3% during the subsequent perennial therapy, and developed (92%) at high single dose of greater than or equal to 1,000 biological units. The majority (69%) were later able to reach the same or higher dose without relapse. Most (62%) patients with major SSE were predicted by high nasal sensitivity before treatment. Only 18% of the patients had immediate local skin reactions of greater than or equal to 2 cm, but delayed local side effects of greater than or equal to 10 cm were recorded in 70%. Immediate skin reactions did not correlate with delayed skin reactions or with SSE, but delayed local side effects tended towards negative correlation with major SSE. A mean area reduction of 50% of the delayed skin reactions was recorded by repetition of a single dose. Subcutaneous nodules appeared at single doses of greater than or equal to 5,000 biological units. Only 5% of the patients contracted nodules during initial preseasonal therapy compared with 38% during subsequent perennial dosage. The nodules contained typical benign granulomas, and the frequency in the two groups was proportionate to the quantity of aluminium in the two extracts.

The biological activity of a partly purified, biochemically/immunochemically characterized mugwort pollen allergen preparation and crude pollen extracts of mugwort, goosefoot and English plantain was determined by means of skin prick test (SPT). The patient inclusion criteria with mugwort were a well-defined positive clinical history and a positive SPT. Symptoms related to goosefoot/English plantain pollens are difficult to define, as these weeds flower during the grass pollen season. Thus patients tested with these allergens did not fulfill the most important inclusion criterion for so-called biological standardization. To elicit a wheal of the same size as that produced by histamine 1 mg/ml required 100 to 10,000 times more material from these weeds, than from mugwort and other pollen allergen extracts investigated earlier. One thousand Biological Units/ml (BU/ml) corresponded to 8.3 micrograms dry weight (dw/ml) of the crude and 1.8 micrograms dw/ml of the purified mugwort pollen allergen preparation. Only 7/22 goosefoot-and English plantain-tested patients were positive at conjunctival or nasal challenge. All three weeds showed a similar composition with 5-10 allergens by CIE/CRIE analysis and 10-13 by immunoblotting analysis. One dominating allergen (approx. 15,000 d), could be identified for each weed species by protein gel blot after separation by SDS g-PAGE. There was no other explanation for the difference in biological activity than the criteria of selection. If there is no obvious clinical history, which is the main patient inclusion criterion in biological standardization, then additional criteria should be used.

The study has been conducted an one hundred children with positive anamnesis for eczema, nasal obstruction, restriction of larynx and/or trachea and bronchus, under-hearing and nightly snoring. The use of the method of bronchial stimulation test with food has demonstrated to useful in the diagnosis of food allergens. Examination of food's allergen allowed me to formulate a table of foods allergenicity and to underline some anamnestic and physiopathologic data of lung capacity and the opening of nasal ways associated with food allergy. I've noted some important rays and bronchoscopic data in association with particular kinds of symptomatology due to the foods introduction. The exclusion of foods thought responsible of the obstructive symptomatology in the subjects caused the return to normality of spirometers rhinomanometric values and, in the subjects rather deaf, of audiometric and impedantiometric values.