PROBLEM TO BE SOLVED: To provide a molecule which can be used as a universal M cell marker, having general-purpose properties that are superior to those of UEA-1 (Ulex europaeus agglutinin-1) which is a conventional M cell marker, and to provide a medical drug that utilizes the molecule and a means, or the like, which is useful for the development of medical drugs.SOLUTION: A method for detecting or identifying the M cell includes a means for measuring the expression of GP2 (glycoprotein 2), wherein a reagent or a kit for detecting or identifying the M cell comprises one or more means of measuring the GP2 a drug delivery medium comprises a GP2 targeting molecule the medical drug comprises the GP2 targeting molecule and an active ingredient as the pharmaceutical a regulator of mucosal immunity comprises a substance capable of regulating the expression or the function of the GP2 the M cell, in which the expression of the GP2 is regulated, is provided, or a tissue containing the M cell is provided a method for evaluating endocytosis in the M cell includes measuring the expression or the function of the GP2, in the M cell or the tissue containing the M cell a binder for a microorganism comprises the GP2 in a secreted form a complex comprises the GP2 and the microorganism or a component thereof and a method, and so on, for evaluating the mucosal immunity in a mammal are provided.COPYRIGHT: (C)2008,JPO&INPIT【課題】従来のM細胞マーカーであるUEA-1よりも汎用性に優れた、汎M細胞マーカーとして使用できる分子、及びそれを利用した医薬及び医薬の開発に有用な手段などの提供。【解決手段】GP2の発現を測定することを含む、M細胞の検出又は同定方法;1以上のGP2測定用手段を含む、M細胞の検出又は同定用試薬又はキット;GP2ターゲティング分子を含む薬物送達媒体;GP2ターゲティング分子及び医薬としての有効成分を含む医薬;GP2の発現又は機能を調節し得る物質を含む、粘膜免疫の調節剤;GP2の発現が調節されたM細胞又はそれを含む組織;M細胞又はそれを含む組織においてGP2の発現又は機能を測定することを含む、M細胞におけるエンドサイトーシスの評価方法;分泌形態のGP2を含む、微生物に対する結合剤;GP2及び微生物又はその成分を含む複合体;哺乳動物における粘膜免疫の評価方法など。【選択図】なし
