Synthetic vaccines constitute the most promising tools for controlling and preventing infectious diseases. When synthetic immunogens are designed from the pathogen native sequences, these are normally poorly immunogenic and do not induce protection, as demonstrated in our research. After attempting many synthetic strategies for improving the immunogenicity properties of these sequences, the approach consisting of identifying high binding motifs present in those, and then performing specific changes on amino-acids belonging to such motifs, has proven to be a workable strategy. In addition, other strategies consisting of chemically introducing non-natural constraints to the backbone topology of the molecule and modifying the α-carbon asymmetry are becoming valuable tools to be considered in this pursuit. Non-natural structural constraints to the peptide backbone can be achieved by introducing peptide bond isosters such as reduced amides, partially retro or retro-inverso modifications or even including urea motifs. The second can be obtained by strategically replacing L-amino-acids with their enantiomeric forms for obtaining both structurally site-directed designed immunogens as potential vaccine candidates and their Ig structural molecular images, both having immuno-therapeutic effects for preventing and controlling malaria.
合成疫苗是控制和预防传染病最有前景的工具。当合成免疫原是根据病原体的天然序列设计时,这些免疫原通常免疫原性较差,无法诱导保护,如我们的研究所示。在尝试多种合成策略以提高这些序列的免疫原性后,我们发现一种可行的策略是识别其中高结合位点的特征,并对属于这些位点的
氨基酸进行特定的改动。此外,其他一些策略也越来越受到重视,包括通过
化学方式在分子的主干拓扑上引入非天然限制,以及修改α-碳不对称性。通过引入肽键异构体(如还原酰胺、部分逆转或逆转修饰,甚至包含
脲基团)可以实现对肽主干的非天然结构限制。后者可以通过策略性地用其对映体替换L-
氨基酸来获得,以获取具有结构特异性设计的免疫原,作为潜在疫苗候选者及其免疫球蛋白结构分子图像,这两者都对预防和控制疟疾具有免疫治疗效果。