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Background: We identified five Gryptorneria japonica trees producing Cry j 1 isoforms that cannot be detected in a sandwich ELISA using two monoclonal antibodies, J1B01 and J1B01, suggesting that the binding affinity of these isoforms for both monoclonal antibodies is low. Objectives: The binding properties of the Cryj 1 isoforms produced by five trees to J1B01 and J1B01 were examined. The complementary DNA (cDNA) sequences of the Cry j 1 isoforms were also determined. Methods: To clarify the binding properties of these Cryj 1 isoforms to J1B01 and J1B01, Cryj 1 was quantified in pollen samples collected from each of the five trees, by sandwich ELISAs using polyclonal antibodies and either J1BOT or J1B01. The cDNA sequences of isoforms with different binding properties were determined. To test the assumption that amino acid substitutions affect the binding affinities of Cry j 1 isoforms for monoclonal antibodies, cleaved amplified polymorphic sequences (CAPS) markers representing the putative polymorphisms were used to analyse additional trees. Results: Four of the five trees produced Cry j 1 isoforms with extremely low binding affinity for J1B01, whereas the other tree produced two different isoforms with low binding affinity for either J 1 BO 1 or J 1 B07. Cry j 1-encoding cDNA sequences for one of the four trees and for the exceptional fifth tree indicate that amino acid substitutions at positions 55 and 352 in mature Cry j 1 affect its binding to J1B01 and J1B01, respectively. This was supported by the results of CAPS analysis. Conclusion: The existence of Cry j 1 isoforms with low binding affinity for either J1B01 or J1B01 was established. Furthermore, a single amino acid substitution is involved in this difference in binding affinity for each monoclonal antibody. [ABSTRACT FROM AUTHOR]

T-cell epitopes of Der p II, a major allergen of Dermatophagoides pteronyssinus, were analyzed by using human T-cell clones. We tested 38 cloned T cells from two Japanese patients with allergic rhinitis, and identified at least two peptides (K33-T47 and I58-C73) as helper T-cell epitopes. The former epitope was shown to be restricted by HLA-DRB1*1502, and the latter by HLA-DRB1*0405, both of which are typical Japanese HLA-DR alleles, suggesting that those T-cell epitopes might be important for the onset of house-dust mite allergy in the Japanese population. We prepared 15 analog peptides of the HLA- DRB1*1502-restricted 15-mer peptide. Of those 15 residues, five (F35, L37, A39, F41, and E42) were critical for the epitope activity, and three residues (F35, A39, and E42) seemed to be included in anchor motifs for HLA-DRB1*1502. The epitope peptide was also recognized by HLA-DRB1*1502-positive healthy donors; however, only allergic T cells showed Th2 functions. Antigen-presenting cells of nonallergic donors were able to activate allergic T cells to express Th2 function. This seemed to suggest that antigen recognition of T cells, as well as additional unknown factors which promote Th2, rather than Th1, responses, might be important for the onset of house-dust mite allergy. [ABSTRACT FROM AUTHOR]

Two cases of atopic asthma caused by acid protease produced by Candida albicans are reported. Both patients had high levels of serum IgE antibodies against the acid protease and showed positive conjunctival and immediate bronchial responses when challenged with the protease. Significant histamine release was detected in both patients when their peripheral leukocytes were challenged with the protease antigen. These findings clearly showed that C. albicans acid protease is the causative allergen of atopic asthma. [ABSTRACT FROM AUTHOR]

Responses of peripheral blood mononuclear cells to synthetic oligopeptides of Der p IL one of the major allergen molecules of Dermatophagoides pteronyssinus were compared between allergic and nonallergic subjects. Healthy subjects showed positive responses to crude extracts of D. pteronyssinus but only allergic subjects showed elevated cellular responses to Der p II. We synthesized three oligopeptides of Der pII in which motifs of a possible T-cell epitope were included. Of 14 subjects with positive response to Der p II three responded to all three peptides, while five did not respond to any peptide tested. In 11 allergic patients who showed positive response to Der p II responsiveness to the peptide K33-T47 was significantly higher than that to other peptides (P < 0.05)1 All the responding patients were also positive for scratch test to Der p IL suggesting that those epitopes induced IgE-promoting helper T-cell response in allergic persons On the other hand the in vitro cellular responses were not necessarily correlated to IgE production against Der pII in healthy subjects. [ABSTRACT FROM AUTHOR]