The present invention relates to (isolated) recombinant proteins, also referred to as improved MAT (iMAT) molecules, comprising at least one translocation module, at least one targeting module and at least one antigen module, wherein at least one cysteine residue is substituted with a different amino acid residue. Such iMAT molecules are useful specifically as vaccines, e.g. for therapy and/or prevention of allergies and/or infectious diseases and/or prevention of transmission of infectious diseases in equines. The present invention further relates to nucleic acids encoding such iMAT molecules, corresponding vectors and primary cells or cell lines.本發明係關於(經分離)重組蛋白質,亦稱作經改良之MAT(iMAT)分子,其包含至少一個易位模組、至少一個靶向模組及至少一個抗原模組,其中至少一個半胱胺酸殘基係經一不同胺基酸殘基取代。該等iMAT分子特別適用作例如用於治療及/或預防馬之過敏及/或傳染性疾病及/或防止馬之傳染性疾病傳播之疫苗。本發明進一步關於編碼該等iMAT分子之核酸、對應之載體及初級細胞或細胞系。