Compositions and methods for stimulating toll-like receptor 9 (TLR9) are provided. More particularly, immunostimulatory oligonucleotides, methods of enhancing immunostimulatory properties of oligonucleotides, and methods of eliciting immune responses are disclosed herein.本發明提供用於刺激類鐸受體9(TLR9)的組成物以及方法。更具體而言,本文揭示免疫刺激性寡核苷酸、提高寡核苷酸之免疫刺激性性質的方法,以及引起免疫反應的方法。