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At least 19 recordsLinked to original sources
PubMed1977

Allergens in bee venom II. Two new high molecular weight allergenic specificities.

Two new allergenic specificites were detected in honeybee venom and the two corresponding protein substances isolated by gel filtration, immunoadsorption, and ion exchange chromatography. The first of these, allergen B, has a molecular weight ranging from 49,000 to more than 200,00 d and can be recognized by rabbit and guinea pig antisera as well as by human reaginic sera using the radioallergosorbent test (RAST). Allergen B gives a single line in immunodiffusion distinct from hyaluronidase, phospholipase A, melittin, and the other high molecular weight substances described and gives a single band at 49,000 d in sodium dodecyl sulfate (SDS) polyacrylamide gel. The second substance, allergen C, has a molecular weight of 105,000 d and was separated from allergen B by immunoadsorption with insoluble antibody. Allergen C was shown to be distinct from the other sustances in bee venom by immunodiffusion with animal antisera. One human reaginic serum was monospecific for allergen C. Two other minor components of 86,000 and 71,000 d are present in bee venom; their allergenic activities are unknown. The two specifities, B and C, comprise most of the reactivity of the previously described Sephadex G-75 fraction 1 and clearly are important allergens, reacting with 98% of sera from bee venom-allergic individuals.

Allergens↗
PubMed1978

Suppression of reaginic antibodies with modified allergens. I. Reduction in allergenicity of protein allergens by conjugation to polyethylene glycol.

The conjugates of ovalbumin (OA) and of the nondialysable constitutents of the aqueous extract of ragweed pollen (RAG) with polyethylene glycols of molecular weights of 6,000 or 20,000 (PEG6 or PEG20) were shown to be nonantigenic, nonallergenic and nonimmunogenic. Thus, the i.v. administration of OA-PEG and RAG-PEG conjugates into mice did not elicit antibodies to OA and RAG, respectively, and these conjugates were shown to suppress in an immunologically specific manner the capacity of these animals to mount primary as well as secondary IgE responses to sensitizing doses of dinitrophenylated OA or of RAG. Moreover, the Peg-modified antigens did not combine either in vitro or in vivo with IgE antibodies directed against the natural antigens. Hence, OA-PEG and RAG-PEG conjugates were incapable of triggering allergic reactions in animals possessing IgE antibodies to the unmodified antigens. These PEG-modified antigens were also shown to be tolerogenic.

Allergens↗
PubMed1976

The allergenic structure of allergen M from cod. I. Tryptic peptides of fragment TM 1.

In attempts to locate the allergenic active sites of fragment TM 1 of allergen M from cod, the allergenicity of the tryptic hydrolysis peptides was examined both in vivo and in vitro. A duodecapeptide (residues No. 33-44) was tentatively suggested to incorporate at least one allergenic determinant. All the tryptic peptides were less active than allergen M as shown by the in vivo titration experiments. The activity of the peptides was not due to contamination of intact allergens.

Allergens↗
PubMed1975

Allergens of mammalian origin. II. Characterization of allergens extracted from rat, mouse, guinea pig, and rabbit pelts.

Aqueous extracts prepared from lyophilized, defatted rat, mouse, guinea pig, and rabbit pelts elicited intense wheal-and-flare responses in the skin of a high proportion of patients who were clinically sensitive to these animals. The major allergens in each extract were nondialyzable. Skin test reactions to rat, mouse, and guinea pig serum were common in patients allergic to these animals. The fractions of rat, mouse, and rabbit pelt extract showing maximum allergenic activity contained proteins with the electrophoretic mobility of serum albumin. Fractions of guinea pig pelt extract with maximum allergenic activity were of prealbumin mobility and contained little stainable protein. On Sephadex G-100 gel filtration, most allergen from rat, mouse, and guinea pig pelt extracts was recovered in fractions containing proteins with a molecular weight range of 10,000 to 25,000 daltons. Allergen in rabbit pelt extract had a slightly higher molecular weight range of 18,000 to 38,000 daltons.

Allergens↗
PubMed1979

Studies on Alternaria allergens. I. Isolation of allergens from Alternaria tenuis and Alternaria solani.

Extracts of Alternaria tenuis and Alternaria solani were separated into dialyzable (molecular weight less than 10,000) and non-dialyzable forms. The latter was further fractionated by gel filtration through Sephadex G-100 followed by ion-exchange chromatography on DEAE-cellulose. The dialyzable material was fractionated by gel filtration through Sephadex G-50. The allergenic activities of the fractions obtained from the A. tenuis extract was measured in vitro by the radioallergosorbent test assay and the allergenic potency was measured by radioallergosorbent test inhibition assay. Allergenic activity was detected in most of the non-dialyzable fractions, the majority of the activity being in the last G-100 fraction (MW approximately 20,000) which was predominantly protein in nature. The same component may be responsible for the activity found in the dialyzate and its first G-50 fraction since the immunodiffusion studies indicated that the last G-100 fraction has antigenic components in common with those of the first G-50 fraction. In addition, cross-reactions between A. tenuis and A. solani extracts show that the two species share common antigenic determinants.

Allergens↗
PubMed1979

Rare allergens - hidden sources of allergens.

Acceleration of technical development results in growing difficulties to trace allergens. In this respect rare allergens as well as hidden sources of well-known allergens not infrequently cause persistence of allergic dermatitis. Examples are presented for di-ethyl-ester of maleic acid, hydroxylammoniumhydrochloride, N-methyl-p-aminophenol, 2-hydroxy-3-naphtoic acid o-aniside and N-acetoacetyl-benzylamide.

Adult↗
PubMed1979

Denaturization of allergen P: effect on allergenicity, antigenicity and immunogenicity.

When allergen P was denatured by 8M urea, the modified molecule still reacted with IgE specific for the native allergen but not with hemagglutinating antibodies. Heating at 100 degrees C abolished the reaction in both cases. The results suggested differences between allergenic and antigenic capacities which may be based on structural differences of the antigenic determinants.

Allergens↗
PubMed1979

The allergenic structure of allergen M from cod. III. Studies on the antigenicity of long-sequence peptides.

Fragments TM 1 (75 amino acid residues) and TM 2 (38 amino acid residues), and 3 other polypeptides (range 16-25 amino acid residues) of Allergen M from cod were shown to be active in rabbit IgG-mediated reactions. The same peptides were previously found to possess reactivity in IgE-mediated reactions, thus suggesting a structural relationship between their antigenic and allergenic determinants.

Absorption↗
PubMed1979

Predictive evaluation in animals of the contact allergenic potential of medically important substances. II. Comparison of different methods of cutaneous sensitization with "weak" allergens.

Results of the optimization method and of other methods used to assess contact allergy in laboratory animals were compared with known epidemiological data on the occurrence of hypersensitivity reactions in man. Tests were performed with preservatives (formalin, ethylenediamine and sorbic acid), drugs (penicillin G, Benzocaine and sulphathiazole) and other contactants belonging to widely different chemical classes (p-phenylenediamine, triclosan, pyrazole derivatives, nickel and chrome salts, eugenol, isoeugenol and mercaptobenzothiazole). The degree of sensitization achieved in guinea pigs by the optimized procedure (intradermal test with adjuvant combination) and the maximization procedure was invariably superior to that produced by the epidermal method using prior irritation of the site of application. Both the optimized procedure and the maximization test seem to be capable of identifying contact allergens that cause hypersensitivity reactions in as few as 1 in 10,000 of the human population as a whole. The optimization test merits consideration as a standardized and efficiently predictive procedure.

Adjuvants, Immunologic↗
PubMed1977

[Has N-isopropyl-N'-phenylparaphenylenediamine a place among standard allergens? Importance of this allergen in rubber intolerance].

Allergic contact dermatitis to N-isopropyl-N'-phenylparaphenylenediamine (IPPD) from rubber is far from being exceptional. Out of a total of 56 cases of allergic contact dermatitis to IPPD, 42 were considered as caused by occupational contacts: 17 cases were found in tyre manufacturers, 9 in car-mechanics, 9 in drivers, and 7 in various industrial branches. Out of the 56 cases, 23 also reacted allergically to mercaptobenzothiazole or to tetramethylthiuramdisulphide, or to both of these substances. In a chromatographic analysis of samples of 9 different tyre brands, IPPD was found in 8 cases.

Allergens↗
PubMed1978

Reactivity of ragweed allergens with IgE antibodies. Analyses by leukocyte histamine release and the radioallergosorbent test and determination of cross-reactivity.

Five distinct proteins with allergenic activity have been isolated from short ragweed pollen. We initially tested three of these, AgE, AgK, and Ra3, for reactivity with IgE antibodies by leukocyte histamine release and by the radioallergosorbent test (RAST). We found highly significant correlations between the reactivities of these allergens by leukocyte histamine release and by the RAST, consistent with the view that both procedures detected comparable allergenic activity. We next tested the allergenic cross-reactivity of all five ragweed allergens. AgE, AgK, Ra3, Ra4, and Ra5, by RAST inhibition. With solid-phase AgE the only nonhomologous inhibitor was AgK, which cross-reacted weakly and required a 140-fold mass excess of AgK compared to AgE. With solid-phase AgK both AgK and AgE produced significant inhibition; AgE was slightly more potent than the homologous AgK, Ra3 and Ra5 were allergenically unique, because only the homologous allergen produced 50% inhibition. Ra4 was weakly inhibited by AgE, Ra3, and Ra5 when these allergens were added in 300- to 5---fold mass excesses; this weak inhibition may represent either cross-reaction or cross-contamination. We found that RAST inhibition could be used as an assay for the individual ragweed allergens and we demonstrated the presence of all of the allergens in a whole ragweed extract. The sensitivity of the RAST inhibition assay ranged from 10 ng to 100 ng for 50% inhibition. Finally, the solid-phase ragweed allergens were used to determine the frequency of elevated IgE antibody levels in 65 patients with ragweed hay fever. Virtually all of the patients reacted with AgE (97%), while 88% reacted with AgK, 51% reacted with Ra3, 28% reacted with Ra4, and 17% reacted with Ra5. These results highlight the usefulness of the RAST as a specific and sensitive tool for immunochemical studies of allergens.

Adolescent↗
PubMed1978

Extraction and analysis of coffee bean allergens.

Workers in the coffee industry can develop occupational allergic disease upon exposure to dust associated with coffee manufacturing. Since controversy exists as to the source or chemical nature of these allergens, the mouse model of reaginic antibody production was used to assess the potential sources of allergens in samples obtained from a local coffee manufacturing plant. Mice were immunized with extracts of coffee dust and beans and the resulting reaginic antibody response determined by the passive cutaneous anaphylaxis reaction. Cross-reacting allergens were detected in samples of coffee dust, cleaner can debris and green coffee beans, but not in chaff or roasted coffee beans. None of the allergens detected in coffee samples cross-reacted with extract of castor beans, although these extracts contained the potent castor bean allergen. Green coffee bean allergens partially purified by gel filtration were heterogeneous with respect to molecular size, although quite similar in their reactivity with reaginic antiserum. These results suggest that the green coffee bean is the major source of allergen in coffee manufacturing plants. This allergen is heterogeneous with respect to size and heat lability, and is immunochemically different from the castor bean allergen.

Allergens↗
PubMed1979

Antigens and allergens in birch pollen extract.

More than 70% of the total allergenic activity of a birch pollen (BP) extract was detected within the first 30 min of extraction. Fractionation of the BP extract by gel filtration and analysis of the eluted antigens by a fused rocket immunoelectrophoresis revealed at least three antigens with molecular weights of about 29 000, and 17 000-10 000, corresponding to antigens Nos. 7-8 and No. 2, respectively, in crossed-immunoelectrophoresis (CIE) and in crossed-radioimmuno-electrophoresis (CRIE). Gel isoelectrofocusing of the pooled allergenic fractions revealed two major protein bands with pI's around 5.6 and 5.7, probably corresponding to antigens Nos.7-8 and No. 2, respectively. Antigens Nos. 7-8 were thermoresistant, while antigen No. 2 was thermolabile. The allergenic activity was determined by prick skin testing and by the RAST inhibition method. More than 90% of the allergenic activity in the fractions was located in the protein peak C (mol. wt. 10 000-17 000) containing antigens 7-8. About 30% of the total allergenic activity of the extract (1:10 w/v) was recovered in the peak C fractions, and only less than 0.5% outside these fractions. Higher allergenic activity was obtained for the peak B fractions (mol. wt. 29 000) by skin prick testing than by the RAST. Peak B contained allergens (antigen 2) distinct from those of peak C by the CRIE and by the RAST. The allergenic material in the low molecular weight fractions of peak D (mol. wt. 2000-5000) was allergenically similar to that of peak C in the RAST. Only weak and even negative skin reactions were observed with the peak D fractions in allergic subjects.

Allergens↗
PubMed1977

Polymerization of mixtures of grass allergens.

Mixed grass pollen allergens were precipitated from crude grass extract by 90% saturation with ammonium sulfate. The precipitate was dissolved and polymerized with glutaraldehyde. Polymerized allergens with a molecular weight range of 200,000 to 4,000,000 were isolated. The resultant grass allergen polymers had reduced allergenicity but were capable of absorbing out IgG antibody from sera of 2 patients treated with crude grass allergens. This alteration of allergenicity was intended to reduce the ability of allergens to react with IgE-sensitized cells rather than to modify or destroy antigenic determinants. Prior exposure of allergens to phenol used as a preservative inhibited the polymerization process probably by blocking combining sites with which glutaraldehyde reacts.

Allergens↗