Provided are: a novel Japanese cypress pollen allergen protein and a Japanese-cypress-pollen-allergy diagnostic agent, prophylactic agent, therapeutic agent, or other agent in which the allergen protein is used. A Japanese cypress pollen allergen selected from (a) to (c), or a peptide fragment thereof: (a) a protein comprising the amino acid sequence represented by SEQ ID: 2 (b) a protein having Japanese cypress pollen allergen activity, the protein comprising the amino acid sequence represented by SEQ ID: 2, and one or a plurality of amino acids being substituted, deleted, or added and (c) a protein having Japanese cypress pollen allergen activity, the protein comprising an amino acid sequence that is at least 90% the same as the amino acid sequence represented by SEQ ID: 2.本發明提供一種新穎之檜木花粉症過敏原蛋白質、及使用其之檜木花粉過敏症之診斷藥、預防藥及治療藥等。本發明係一種選自以下之(a)~(c)中之檜木花粉過敏原或其片段肽:(a) 包含以序列編號2所示之胺基酸序列的蛋白質;(b) 包含於以序列編號2所示之胺基酸序列中置換、缺失或附加一個或數個胺基酸所得之胺基酸序列,且具有檜木花粉過敏原活性的蛋白質;(c) 包含與以序列編號2所示之胺基酸序列具有90%以上之同源性之胺基酸序列,且具有檜木花粉過敏原活性的蛋白質。
