In vitro diagnosis in asthma: the state-of-the-art.

"In vitro assays in asthmatic patients have been exploring the "allergic" component of asthma. Solid-phase IgE tests can supplement or replace skin tests. Histamine release and determination are performed with automated, or RIA/ELISA; however, these assays are still research oriented. More recently, tryptase has been investigated, and the serum levels of this enzyme correlate well with mast-cell activation. But asthma is a multifactorial/facetted syndrome, and these assays provide minimal and specific informations which may just focus on limited etiological aspects of an elusive malady".

[The immunochemical characteristics of allergens]. / Immunokhimicheskaia kharakteristika allergenov.

Modern approaches to the standardization of allergens require the use of not only biological methods, but also a wide range of physicochemical and immunological ones. To obtain Soviet standard samples, the optimum spectrum of methods for their characterization, evaluation and comparison with international standard samples should be definitely selected. After the preliminary study of a number of allergens by different immunochemical methods a set of such methods, including different kinds of electrophoresis, isoelectrofocusing, immunoblotting, etc., are proposed, these methods being considered obligatory for obtaining Soviet standard samples of allergens.

[Comparison of the cutaneous response to Dermatophagoides farinae from 2 separate laboratories]. / Comparación de la respuesta cutánea a Dermatophagoides farinae de dos laboratorios distintos.

We compared in 50 asthmatic children, the cutaneous response by skin prick test to Dermatophagoides farinae with antigens from two different laboratories (Freeman and Hollister). In order to evaluate the importance of the selection, conservation and standardization of the allergic extracts. 27/50 children had a similar response, in those cases (6) where Freeman was doubtful and Hollister positive the allergic etiology was confirmed by RAST and Challenge tests. In 5 cases, Freeman was negative and Hollister doubtful we only confirm allergic etiology in 1. When both were positive all of them were allergic. The antigen Dermatophagoides farinae from Freeman laboratory needs another diagnostic method, when the cutaneous response is doubtful or negative and the clinical feature is highly suggestive. We don't have to forget the importance of the controls positive and negative.

Double-blind, placebo-controlled rush immunotherapy with a standardized Alternaria extract.

Specific immunotherapy is ineffective with unstandardized mold extracts. A double-blind, placebo-controlled study was performed in 24 patients (5 to 56 years of age) only allergic to Alternaria. The extract was standardized by isoelectric focusing, crossed immunoelectrophoresis, crossed radioimmunoelectrophoresis, RAST inhibition, and skin tests and contained allergen Alternaria major allergen a I and antigen B. Thirteen patients received the active treatment, and 11 received the placebo. Immunotherapy was started by a 2-day rush protocol; maintenance injections were administered for 1 year. The patient's self-evaluation of the treatment was significantly (p less than 0.001) lower in the placebo-treated group. Global symptom-medication scores, including asthma and rhinoconjunctivitis, were significantly (p less than 0.005) lower in the actively treated group. Nasal challenges with Alternaria extract were performed before immunotherapy and after 1 year of treatment. There was no difference in the placebo-treated group and a significantly (p less than 0.01) increased mean provocative dose in the actively treated group. Skin tests were significantly reduced in the actively treated group. Specific IgG increased significantly in the actively treated group and were stable in the placebo-treated group. There was a significant correlation between nasal challenges and nasal symptom-medication scores (p less than 0.03) or the patient's self-evaluation of efficacy (p less than 0.05). This study demonstrated that patients only sensitized to Alternaria benefit from specific immunotherapy with a standardized Alternaria extract.

Immunotherapy with a standardized Dermatophagoides pteronyssinus extract. IV. Systemic reactions according to the immunotherapy schedule.

Specific immunotherapy with standardized extracts can induce systemic reactions (SRs), possibly increased by a rush immunotherapy (RIT) protocol. A prospective study in 1152 mite-allergic patients (3 to 63 years of age) examined the incidence of SRs during an RIT or a step protocol. All patients received the same standardized extract of Dermatophagoides pteronyssinus with the same maintenance dose. In the first group, 290 patients had an RIT protocol without any preventive measure. In a second group, the prevention of SRs during RIT was attempted by pretreating 160 patients with methylprednisolone (0.5 mg/kg/day), ketotifen (2 mg/day), and theophylline (10 mg/kg/day). In a third group (479 patients), the same pretreatment was associated with preventive measures and with FEV1 results and the occurrence of large local reactions. A fourth group consisted of 223 patients who received a step protocol with the same pretreatment and preventive measures. The incidence of SRs per patient was 36.2% with RIT alone, 16.2% when the pretreatment was added, and 7.2% when pretreatment and preventive measures were used. Patients receiving the step protocol had 5.4% SRs. Adrenaline had to be used from 10.0%, 4.6%, 0.2%, and 0.2%, respectively. No reaction started 45 minutes or later after the last injection. Children younger than 5 years of age had a significantly greater number of SR.

Aspects of pharmaceutical and chemical standardization of patch test materials.

The choice of vehicle for patch test materials is important for the bioavailability and stability of the allergens. Examples are given from the standardization of the TRUE Test and include caine mix, Kathon CG, and fragrance mix.

Comparison of in-house allergen extracts of Phleum pratense (timothy grass) pollen with the international standard and investigation of IgE specificities of a grass-pollen serum pool from West Germany and of the one recommended by the World Health Organization.

We compared our in-house reference extract (RE) and a production extract (PE) with the international reference preparation (IRP) of International Union of Immunological Societies of timothy-grass pollen, using various biochemical and immunochemical methods. Furthermore, we compared the IgE composition of our in-house grass-pollen serum pool (West Germany) with the serum pool recommended by the World Health Organization, using the RE for crossed radioimmunoelectrophoresis (CRIE). Our extracts (RE and PE) were nearly comparable with the IRP. Only by CRIE one more allergen could be detected in RE and PE than in IRP and in another extract purchased from an American company. This finding may depend on the region where the source materials were harvested and which source materials were used for the preparation of the extracts. Furthermore, by high-performance liquid chromatography in the low-molecular-weight range, two distinct peaks could be detected in the nondiafiltered IRP, which were detected in the diafiltered RE and PE as traces only. The IgE composition of our in-house grass-pollen serum pool was comparable with the serum pool recommended by the World Health Organization, as detected by CRIE using RE.

Use of enzyme-developed immunoblots scanned by densitometry to compare lot-to-lot variability of Russian-thistle extracts.

Two different lots of Russian-thistle extracts from five commercial sources were evaluated by isoelectric focusing, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and immunoblots of Immobilon transfers from these separations. The immunoblots were developed by an enzyme-linked method and scanned with a densitometer. The two lots of a standardized extracts produced scans that suggested uniformity in allergenic components. Several of the nonstandarized extract lots also appeared quite comparable. With further refinement, immunoblotting with densitometric analysis appears to offer an attractive way to standardize allergen extracts.

[Skin reactivity to grass pollen and the mite Dermatophagoides pteronyssinus in the prick-test using 2 types of allergen preparations]. / Reaktivnost koze na polene trava i grinju Dermatophagoides pteronyssinus u prick-testu izvedenom sa dvije vrste alergenskih pripravaka.

The reliability of prick testing with allergen preparations produced in Yugoslavia was assessed by comparison to the internationally accepted ones (Pharmacia Diagnostica) of 100,000 BU activity. The following allergens were used: the mite Dermatophagoides pteronyssinus in 107 subjects, and grass pollens: Dactylis glomerata, Poa pratensis, Phleum pratense and Secale cereale in 39 subjects. The clinical significance of the response was assessed in relation to the skin reaction to the negative control solution and positive histamine control (in concentration of 1 mg/ml). The results indicate that the allergen extract of Dermatophagoides pteronyssinus (3000 PNU/ml) produced in Yugoslavia does not provoke skin reactions comparable to those provoked by the standardized extract of 100,000 BU in contrast to the grass pollen allergens, with the exception of Poa pratensis, which evokes equivalent skin reactions. Thus grass pollen allergens are reliable extracts and can be applied with good confidence in routine work. The need to set more rigorous criteria for assessing skin prick reactions, when domestic, unstandardized products are used, emerged as a result of this study.

Allergenicity of orange juice and orange seeds: a clinical study.

Oranges are considered to be common allergenic fruits in China. They may induce severe food allergy in sensitive individuals. Allergic histories were analyzed in 26 orange-sensitive patients. Intradermal tests with extracts of orange juice and seeds were performed in 16 out of the 26 patients. P-K test was performed in one patient. The allergic history analysis suggested that clinical symptoms of some orange-allergic subjects were different from other fruit allergies but similar to nut and other oil plant seed allergies. The skin test and P-K test showed that the major allergenic components of orange reside in orange seeds instead of orange juice. Systemic reactions developed in 5 patients after intradermal tests with 1:20-200 (w/v) orange seed extracts. We considered that orange seed contains high potent allergens which may induce orange sensitivity due to careless chewing of orange seeds.