Newman David
Newman Consulting LLC, Wayne, PA, USA.
F1000Res. 2017 Jun 5;6:783. doi: 10.12688/f1000research.11221.1. eCollection 2017.
With the advent of very rapid and cheap genome analyses and the linkage of these plus microbial metabolomics to potential compound structures came the realization that there was an immense sea of novel agents to be mined and tested. In addition, it is now recognized that there is significant microbial involvement in many natural products isolated from "nominally non-microbial sources". This short review covers the current screening methods that have evolved and one might even be tempted to say "devolved" in light of the realization that target-based screens had problems when the products entered clinical testing, with off-target effects being the major ones. Modern systems include, but are not limited to, screening in cell lines utilizing very modern techniques (a high content screen) that are designed to show interactions within cells when treated with an "agent". The underlying principle(s) used in such systems dated back to unpublished attempts in the very early 1980s by the pharmaceutical industry to show toxic interactions within animal cells by using automated light microscopy. Though somewhat successful, the technology was not adequate for any significant commercialization. Somewhat later, mammalian cell lines that were "genetically modified" to alter signal transduction cascades, either up or down, and frequently linked to luciferase readouts, were then employed in a 96-well format. In the case of microbes, specific resistance parameters were induced in isogenic cell lines from approximately the mid-1970s. In the latter two cases, comparisons against parent and sibling cell lines were used in order that a rapid determination of potential natural product "hits" could be made. Obviously, all of these assay systems could also be, and were, used for synthetic molecules. These methods and their results have led to a change in what the term "screening for bioactivity" means. In practice, versions of phenotypic screening are returning, but in a dramatically different scientific environment from the 1970s, as I hope to demonstrate in the short article that follows.
随着非常快速且廉价的基因组分析的出现，以及这些分析与微生物代谢组学和潜在化合物结构的关联，人们意识到有大量新型药物有待挖掘和测试。此外，现在人们认识到，许多从“名义上的非微生物来源”分离出的天然产物都有微生物的显著参与。这篇简短的综述涵盖了目前已经发展起来的筛选方法，鉴于基于靶点的筛选在产品进入临床试验时出现问题，尤其是脱靶效应成为主要问题，有人甚至可能会说这些方法“退化”了。现代系统包括但不限于利用非常现代的技术（高内涵筛选）在细胞系中进行筛选，这些技术旨在显示用“药物”处理时细胞内的相互作用。此类系统所使用的基本原理可追溯到20世纪80年代初制药行业未发表的尝试，即通过自动光学显微镜显示动物细胞内的毒性相互作用。尽管取得了一定成功，但该技术还不足以实现任何重大的商业化。稍晚些时候，人们采用了经过“基因改造”以改变信号转导级联反应（上调或下调）且常与荧光素酶读数相关联的哺乳动物细胞系，以96孔板形式进行实验。对于微生物，从20世纪70年代中期左右开始在同基因细胞系中诱导特定的抗性参数。在后两种情况下，通过与亲本和同胞细胞系进行比较，以便能够快速确定潜在的天然产物“命中物”。显然，所有这些检测系统也都可以并且确实被用于合成分子。这些方法及其结果导致了“生物活性筛选”一词含义的改变。实际上，表型筛选的版本正在回归，但所处的科学环境与20世纪70年代截然不同，正如我希望在接下来的短文中展示的那样。
