For the cedar pollen antigen proteins Cryj I and Cryj II which have been identified as the antigens causing cedar pollen allergy, the T cell epitope (12-19 amino acids), recognized by the cedar allergen specific T cells, has been investigated in detail. Then, based on the idea that if the T-cell epitopes of cedar allergen could be accumulated in the daily ingested rice, "the rice possibly offering the effects of mitigating or curing the Japanese cedar pollinosis by ingestion" could be developed based on the oral immune tolerance phenomenon, the epitope peptide accumulated rice was developed.

Nucleotide sequence to express the part of amino acid sequence contained in the antigen proteins Cryj I and Cryj II in the cedar pollens causing pollen allergy and recognized by the human cedar pollen antigen-specific T cell (hereinafter referred to as “human T cell epitope”.

At a total of seven (7) sites, three (3) in Cryj I and four (4) in Cryj II, the human T-cell epitopes, composed of 12 to 19 amino acid residues in length respectively, have been identified. In order to express the artificial peptide (7Crp) composed of 96 amino acid residues by linking the seven-site epitopes (amino acid sequence), the artificial gene was synthesized in accordance with the amino acid sequence of T cell epitope. For the synthesis, the frequently used codon was selected among the gene cluster which encodes the major rice seed storage proteins.