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其外围的多个功能基团。其中，芳香族聚酰胺树枝状聚合物容易制备，并且具有由芳香酰胺结构引起的强疏水性和基于氢键的相互作用。p53突变蛋白是癌细胞中最常见的蛋白质之一。p53突变体加速肿瘤细胞的生长，尽管野生型p53被认为是肿瘤的抑制因子。为了制备抗p53突变体的高效价抗体，本工作制备了寡肽-聚酰胺树枝状大分子复合物作为多抗原肽，并初步将热休克蛋白10（HSP 10）连接到聚酰胺树枝状大分子末端。HSP 10-树枝状聚合物缀合物显示针对抗HSP 10抗体的抗原-抗体相互作用。将含有p53突变热点的寡肽（R248 Q）通过发散或会聚的方式共价连接到四价芳香聚酰胺树枝状大分子上。四取代肽-聚酰胺缀合物的形成通过收敛方法证实。由于肽的强亲水性，所得缀合物可溶于水。通过GPC测量确认缀合物在水中的二聚体形成。兔对偶联物的免疫应答目前尚不成功，仍在研究中。从抗体制备的角度来看，与具有较强疏水性的大聚酰胺树枝状聚合物的缀合可能是合适的选择。

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.