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

树状大分子具有独特的三维结构和位于外围的多个官能团的特点。其中，芳香聚酰胺树状大分子制备简便，具有较强的疏水性和由芳香酰胺结构引起的氢键基相互作用。p53突变蛋白是癌细胞中最常观察到的蛋白之一。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。在本研究中，我们制备了寡肽-聚酰胺树状聚合物偶联物作为多抗原肽，以制备p53突变体的高滴度抗体。作为初步研究，热休克蛋白10（HSP10）被偶联到聚酰胺树状大分子的末端。hsp10 -树突状分子偶联物对抗hsp10抗体表现出抗原-抗体相互作用。这一事实表明，HSP10的亲水部分暴露在水中，树突分子作为亲水肽的载体。含有p53突变热点的寡肽（R248Q）通过发散或趋同途径与四价芳香族聚酰胺树状大分子共价连接。四取代肽-聚酰胺偶联物的形成用收敛法证实。由于多肽的亲水性强，所得到的偶联物可溶于水。通过GPC测量证实了共轭物在水中的二聚体形成。目前兔对偶联物的免疫反应尚不成功，仍在研究中。从制备抗体的角度来看，与疏水性较强的大聚酰胺树状大分子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.