Preparation and Immunological Study for Oligopeptide-Dendrimer Conjugates as Multiple Antigen Peptide for p53 Mutant

树枝状大分子具有独特的三维结构和位于外围的多个官能团。其中，芳香族聚酰胺树枝状大分子制备简单，具有很强的疏水性和芳香族酰胺结构引起的氢键相互作用。这种名为P53突变体的蛋白质是癌细胞中最常见的蛋白质之一。尽管野生型p53被认为是肿瘤的抑制因子，但突变型p53可加速肿瘤细胞的生长。在本工作中，我们制备了寡肽-聚酰胺树状大分子结合物作为多抗原肽，以制备高效价的p53突变体抗体。作为初步研究，我们将一种小蛋白-热休克蛋白10(HSP10)偶联到聚酰胺树枝状大分子的末端。HSP10-树枝状大分子偶联物具有抗HSP10抗体的抗原-抗体相互作用。这表明HSP10的亲水链段暴露在水中，树枝状大分子作为亲水性多肽的载体。含有P53突变热点的寡肽(R248Q)通过发散或收敛的方式与四价芳香聚酰胺树枝状大分子共价连接。用收敛方法证实了四取代多肽-聚酰胺偶联物的形成。由于多肽具有很强的亲水性，所得结合物可溶于水。凝胶渗透色谱(GPC)测量证实了偶联物在水中形成了二聚体。目前，这些偶联物对兔的免疫应答尚不成功，目前仍在研究中。从制备抗体的角度来看，与疏水性较强的大分子聚酰胺树枝状大分子的偶联可能是一种合适的选择。

Dendrimers are characterized by unique three-dimensional architecture and multiple functional groups located at the periphery. Among them, aromatic polyamide dendrimers are readily prepared and have strong hydrophobicity and hydrogen-bond-based interaction caused by the aromatic amide structure. The protein, p53 mutant, is one of the most frequently observed proteins in cancer cells. The p53 mutant accelerates growth of tumor cells although wild type p53 is known as a suppressor for tumors. In this work, we have prepared oligopeptide-polyamide dendrimer conjugates as multiple antigen peptide in order to prepare high-titer antibodies for p53 mutant.As a preliminary study, a small protein, heat shock protein 10(HSP10), was conjugated to the terminal of polyamide dendrimers. The HSP10-dendrimer conjugates showed antigen-antibody interaction against anti-HSP10 antibody. The fact implies that the hydrophilic segment of HSP10 is exposed in water and the dendrimer acts as a carrier for hydrophilic peptides.Oligopeptide containing a hot spot of p53 mutation (R248Q) was covalently connected to tetra-valent aromatic polyamide dendrimers via divergent or convergent approach. The formation of tetra-substituted peptide-polyamide conjugates was confirmed by the convergent approach. The resulting conjugates were soluble in water due to strong hydrophilic nature of the peptides. Dimer formation of the conjugates in water was confirmed by GPC measurements. Immune response of the conjugates by rabbits is not successful at this moment and still under investigation. The conjugation to large polyamide dendrimers which have stronger hydrophobicity might be a suitable choice from the view point of the preparation of antibodies.